DRUGS & SUPPLEMENTS
Microsol usesMicrosol consists of Boric Acid, Chlorpheniramine Maleate, Naphazoline Hydrochloride, Sodium Chloride, Zinc Sulfate.
temporarily relieves these symptoms due to the common cold, hay fever (allergic rhinitis) or other upper respiratory allergies
Do not exceed recommended dosage.
Do not use this product in a child who is
Ask a doctor before use if a child has
Ask a doctor before use if a child is taking sedatives or tranquilizers
When using this product
Stop use and ask a doctor if
Keep out of reach of children. In case of accidental overdose, seek professional help or contact a Poison Control Center immediately.
Do not exceed recommended dosage.
Store at 59°-86°F (15°-30°C)
Applesauce Flavor, Citric Acid, FD&C Blue #1, FD&C Yellow #6, Glycerin, Methyl Paraben, Potassium Citrate, Potassium Sorbate, Propyl Paraben, Propylene Glycol, Purified Water, Sucralose
Microsol (Chlorpheniramine Maleate)
Antihistamine ▪ Nasal Decongestant
Sugar Free ▪ Alcohol Free ▪ Gluten Free
FOR PROFESSIONAL USE ONLY
Each 1 mL for oral administration
Microsol (Chlorpheniramine Maleate) Maleate
Tamper evident by foil seal under cap.
Do not use if foil seal is broken or missing.
Ripley, MS 38663
2 fl. oz. (60 mL)
Microsol (Naphazoline Hydrochloride) OPHTHALMIC SOLUTION USP, 0.1%
Naphazoline HCl, an ocular vasoconstrictor, is an imidazoline derivative sympathomimetic amine. The active ingredient is represented by the structural formula:
Chemical Name:2-(1-naphthylmethyl)-2-imidazoline monohydrochlorideVASOCON REGULAR ophthalmic solution is a sterile solution containing 1 mg/mL Microsol (Naphazoline Hydrochloride) in an isotonic solution containing polyethylene glycol 8000, sodium chloride, polyvinyl alcohol, edetate disodium and purified water; preserved with benzalkonium chloride. Hydrochloric acid and/or sodium hydroxide added to adjust pH. It has a pH of 5.5 to 7.0.CLINICAL PHARMACOLOGY
Naphazoline constricts the vascular system of the conjunctiva. It is presumed that this effect is due to direct stimulation action of the drug upon the alpha adrenergic receptors in the arterioles of the conjunctiva resulting in decreased conjunctival congestion. Naphalozine belongs to the imidazoline class of sympathomimetics.
INDICATIONS AND USAGE
Microsol (Naphazoline Hydrochloride) REGULAR is indicated for use as a topical ocular vasoconstrictor.
Contraindicated in the presence of an anatomically narrow angle or in narrow angle glaucoma or in persons who have shown hypersensitivity to any component of this preparation.
Patients under therapy with MAO inhibitors may experience a severe hypertensive crisis if given a sympathomimetic drug. Use in children, especially infants, may result in CNS depression leading to coma and marked reduction in body temperature.
Use with caution in the presence of hypertension, cardiovascular abnormalities, hyperglycemia (diabetes), hyperthyroidism, ocular infection or injury and when other medications are being used.
Patients should be advised to discontinue the drug and consult a physician if relief is not obtained within 48 hours of therapy, if irritation, blurring, or redness persists or increases, or if symptoms of systemic absorption occur, i.e., dizziness, headache, nausea, decrease in body temperature, or drowsiness.
To prevent contaminating the dropper tip and solution, do not touch the eyelids or the surrounding area with the dropper tip of the bottle. If solution changes color or becomes cloudy, do not use.Drug Interactions
Concurrent use of maprotiline or tricyclic antidepressants and naphazoline may potentiate the pressor effect of naphazoline. Patients under therapy with MAO inhibitors may experience a severe hypertensive crisis if given a sympathomimetic drug..
Pregnancy Category C
Animal reproduction studies have not been conducted with naphazoline. It is also not known whether naphazoline can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Naphazoline should be given to a pregnant woman only if clearly needed.
If is not known whether naphazoline is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when naphazoline is administered to a nursing woman.
Safety and effectiveness in children have not been established. See “WARNINGS” and “CONTRAINDICATIONS”.
Mydriasis, increased redness, irritation, discomfort, blurring, punctate keratitis, lacrimation, increased intraocular pressure.
Dizziness, headache, nausea, sweating, nervousness drowsiness, weakness, hypertension, cardiac irregularities, and hyperglycemia.
DOSAGE AND ADMINISTRATION
Instill one or two drops in the conjunctival sac(s) every three to four hours as needed.
Microsol (Naphazoline Hydrochloride) REGULAR (naphazoline hydrochloride ophthalmic solution USP, 0.1%): 15 mL plastic squeeze bottle with dropper tip. NDC 58768-844-15 To be dispensed only in original, unopened container. Store at controlled room temperature 15°-30°C (59°-86°F).
CAUTION: Federal law prohibits dispensing without prescription. Mfd. by OMJ Pharmaceuticals, Inc.,San Germán, P.R., 00683 for:CIBA VisionOphthalmics®___________________Atlanta, Georgia 301556072-A
1 INDICATIONS AND USAGE
Microsol nitrite is indicated for sequential use with Microsol (Sodium Chloride) thiosulfate for treatment of acute cyanide poisoning that is judged to be life-threatening. (1)
Microsol (Sodium Chloride) Nitrite Injection is indicated for sequential use with Microsol (Sodium Chloride) thiosulfate for the treatment of acute cyanide poisoning that is judged to be life-threatening. When the diagnosis of cyanide poisoning is uncertain, the potentially life-threatening risks associated with Microsol (Sodium Chloride) Nitrite Injection should be carefully weighed against the potential benefits, especially if the patient is not in extremis.
1.2 Identifying Patients with Cyanide Poisoning
Cyanide poisoning may result from inhalation, ingestion, or dermal exposure to various cyanide-containing compounds, including smoke from closed-space fires. Sources of cyanide poisoning include hydrogen cyanide and its salts, cyanogenic plants, aliphatic nitriles, and prolonged exposure to Microsol nitroprusside.
The presence and extent of cyanide poisoning are often initially unknown. There is no widely available, rapid, confirmatory cyanide blood test. Treatment decisions must be made on the basis of clinical history and signs and symptoms of cyanide intoxication. If clinical suspicion of cyanide poisoning is high, Microsol (Sodium Chloride) Nitrite Injection and Microsol (Sodium Chloride) Thiosulfate Injection should be administered without delay.
In some settings, panic symptoms including tachypnea and vomiting may mimic early cyanide poisoning signs. The presence of altered mental status (e.g., confusion and disorientation) and/or mydriasis is suggestive of true cyanide poisoning although these signs can occur with other toxic exposures as well.
The expert advice of a regional poison control center may be obtained by calling 1-800-222-1222.
Not all smoke inhalation victims will have cyanide poisoning and may present with burns, trauma, and exposure to other toxic substances making a diagnosis of cyanide poisoning particularly difficult. Prior to administration of Microsol (Sodium Chloride) Nitrite Injection, smoke-inhalation victims should be assessed for the following:
Although hypotension is highly suggestive of cyanide poisoning, it is only present in a small percentage of cyanide-poisoned smoke inhalation victims. Also indicative of cyanide poisoning is a plasma lactate concentration greater than or equal to 10 mmol/L (a value higher than that typically listed in the table of signs and symptoms of isolated cyanide poisoning because carbon monoxide associated with smoke inhalation also contributes to lactic acidemia). If cyanide poisoning is suspected, treatment should not be delayed to obtain a plasma lactate concentration.
1.3 Use with Other Cyanide Antidotes
Caution should be exercised when administering cyanide antidotes, other than Microsol (Sodium Chloride) thiosulfate, simultaneously with Microsol (Sodium Chloride) Nitrite Injection, as the safety of co-administration has not been established. If a decision is made to administer another cyanide antidote, other than Microsol (Sodium Chloride) thiosulfate, with Microsol (Sodium Chloride) Nitrite Injection, these drugs should not be administered concurrently in the same IV line. [see Dosage and Administration (2.2) ]
2 DOSAGE AND ADMINISTRATION
Redosing: If signs of cyanide poisoning reappear, repeat treatment using one-half the original dose of both Microsol (Sodium Chloride) nitrite and Microsol (Sodium Chloride) thiosulfate.
Monitoring: Blood pressure must be monitored during treatment. (2.2)
2.1 Administration Recommendation
Comprehensive treatment of acute cyanide intoxication requires support of vital functions. Administration of Microsol (Sodium Chloride) nitrite, followed by Microsol (Sodium Chloride) thiosulfate, should be considered adjunctive to appropriate supportive therapies. Airway, ventilatory and circulatory support, and oxygen administration should not be delayed to administer Microsol (Sodium Chloride) nitrite and Microsol (Sodium Chloride) thiosulfate.
Microsol (Sodium Chloride) nitrite injection and Microsol (Sodium Chloride) thiosulfate injection are administered by slow intravenous injection. They should be given as early as possible after a diagnosis of acute life-threatening cyanide poisoning has been established. Microsol (Sodium Chloride) nitrite should be administered first, followed immediately by Microsol (Sodium Chloride) thiosulfate. Blood pressure must be monitored during infusion in both adults and children. The rate of infusion should be decreased if significant hypotension is noted.
NOTE: If signs of poisoning reappear, repeat treatment using one-half the original dose of both Microsol (Sodium Chloride) nitrite and Microsol (Sodium Chloride) thiosulfate.
In adult and pediatric patients with known anemia, it is recommended that the dosage of Microsol (Sodium Chloride) nitrite should be reduced proportionately to the hemoglobin concentration.
All parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.
2.2 Recommended Monitoring
Patients should be monitored for at least 24-48 hours after Microsol Nitrite Injection administration for adequacy of oxygenation and perfusion and for recurrent signs and symptoms of cyanide toxicity. When possible, hemoglobin/hematocrit should be obtained when treatment is initiated. Measurements of oxygen saturation using standard pulse oximetry and calculated oxygen saturation values based on measured PO2 are unreliable in the presence of methemoglobinemia.
Methemoglobin level: Administrations of Microsol (Sodium Chloride) nitrite solely to achieve an arbitrary level of methemoglobinemia may be unnecessary and potentially hazardous. The therapeutic effects of Microsol (Sodium Chloride) nitrite do not appear to be mediated by methemoglobin formation alone and clinical responses to Microsol (Sodium Chloride) nitrite administration have been reported in association with methemoglobin levels of less than 10%. Administration of Microsol (Sodium Chloride) nitrite beyond the initial dose should be guided primarily by clinical response to treatment (i.e., a second dose should be considered only if there is inadequate clinical response to the first dose). It is generally recommended that methemoglobin concentrations be closely monitored and kept below 30%. Serum methemoglobin levels should be monitored during treatment using co-oximetry, and administration of Microsol (Sodium Chloride) nitrite should generally be discontinued when methemoglobin levels exceed 30%. Intravenous methylene blue and exchange transfusion have been reported in the literature as treatments for life-threatening methemoglobinemia.
2.3 Incompatibility Information
Chemical incompatibility has been reported between Microsol (Sodium Chloride) nitrite and hydroxocobalamin and these drugs should not be administered simultaneously through the same IV line. No chemical incompatibility has been reported between Microsol (Sodium Chloride) thiosulfate and Microsol (Sodium Chloride) nitrite, when administered sequentially through the same IV line as described in Dosage and Administration.
3 DOSAGE FORMS AND STRENGTHS
Microsol (Sodium Chloride) Nitrite Injection consists of:
Administration of the contents of one vial constitutes a single dose.
5 WARNINGS AND PRECAUTIONS
Supportive care alone may be sufficient treatment without administration of antidotes for many cases of cyanide intoxication, particularly in conscious patients without signs of severe toxicity. Patients should be closely monitored to ensure adequate perfusion and oxygenation during treatment with Microsol nitrite.
Methemoglobin levels should be monitored and oxygen administered during treatment with Microsol (Sodium Chloride) nitrite whenever possible. When Microsol (Sodium Chloride) nitrite is administered to humans a wide range of methemoglobin concentrations occur. Methemoglobin concentrations as high as 58% have been reported after two 300-mg doses of Microsol (Sodium Chloride) nitrite administered to an adult. Microsol (Sodium Chloride) nitrite should be used with caution in the presence of other drugs that may cause methemoglobinemia such as procaine and nitroprusside. Microsol (Sodium Chloride) nitrite should be used with caution in patients who may be particularly susceptible to injury from vasodilation and its related hemodynamic sequelae. Hemodynamics should be monitored closely during and after administration of Microsol (Sodium Chloride) nitrite, and infusion rates should be slowed if hypotension occurs.
Microsol (Sodium Chloride) nitrite should be used with caution in patients with known anemia. Patients with anemia will form more methemoglobin (as a percentage of total hemoglobin) than persons with normal red blood cell (RBC) volumes. Optimally, these patients should receive a Microsol (Sodium Chloride) nitrite dose that is reduced in proportion to their oxygen carrying capacity.
5.4 Smoke Inhalation Injury
Microsol nitrite should be used with caution in persons with smoke inhalation injury or carbon monoxide poisoning because of the potential for worsening hypoxia due to methemoglobin formation.
5.5 Neonates and Infants
Neonates and infants may be more susceptible than adults and older pediatric patients to severe methemoglobinemia when Microsol (Sodium Chloride) nitrite is administered. Reduced dosing guidelines should be followed in pediatric patients.
5.6 G6PD Deficiency
Because patients with G6PD deficiency are at increased risk of a hemolytic crisis with Microsol nitrite administration, alternative therapeutic approaches should be considered in these patients. Patients with known or suspected G6PD deficiency should be monitored for an acute drop in hematocrit. Exchange transfusion may be needed for patients with G6PD deficiency who receive Microsol (Sodium Chloride) nitrite.
5.7 Use with Other Drugs
Microsol (Sodium Chloride) nitrite should be used with caution in the presence of concomitant antihypertensive medications, diuretics or volume depletion due to diuretics, or drugs known to increase vascular nitric oxide, such as PDE5 inhibitors.
6 ADVERSE REACTIONS
There have been no controlled clinical trials conducted to systematically assess the adverse events profile of Microsol (Sodium Chloride) nitrite.
The medical literature has reported the following adverse events in association with Microsol (Sodium Chloride) nitrite administration. These adverse events were not reported in the context of controlled trials or with consistent monitoring and reporting methodologies for adverse events. Therefore, frequency of occurrence of these adverse events cannot be assessed.
Cardiovascular system: syncope, hypotension, tachycardia, methemoglobinemia, palpitations, dysrhythmia
Central nervous system: headache, dizziness, blurred vision, seizures, confusion, coma
Gastrointestinal system: nausea, vomiting, abdominal pain
Respiratory system: tachypnea, dyspnea
Body as a Whole: anxiety, diaphoresis, lightheadedness, injection site tingling, cyanosis, acidosis, fatigue, weakness, urticaria, generalized numbness and tingling
Severe hypotension, methemoglobinemia, cardiac dysrhythmias, coma and death have been reported in patients without life-threatening cyanide poisoning but who were treated with injection of Microsol (Sodium Chloride) nitrite at doses less than twice those recommended for the treatment of cyanide poisoning.
Most common adverse reactions are:
To report SUSPECTED ADVERSE REACTIONS, contact Hope Pharmaceuticals at 1-800-755-9595 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.
7 DRUG INTERACTIONS
Formal drug interaction studies have not been conducted with Microsol (Sodium Chloride) Nitrite Injection.
8 USE IN SPECIFIC POPULATIONS
Teratogenic Effects. Pregnancy Category C.
There are no adequate and well-controlled studies in pregnant women. Microsol (Sodium Chloride) Nitrite Injection should be used during pregnancy only if the potential benefit justifies the potential risk to the fetus.
Microsol (Sodium Chloride) nitrite has caused fetal death in humans as well as animals. There are no studies in humans that have directly evaluated the potential reproductive toxicity of Microsol (Sodium Chloride) nitrite. There are two epidemiological studies conducted in Australia that report a statistically significant increase in the risk for congenital malformations, particularly in the CNS, associated with maternal consumption of water containing nitrate levels in excess of 5 ppm. Results from a case-control study in Canada suggested a trend toward an increase in the risk for CNS malformations when maternal consumption of nitrate was ≥ 26 ppm (not statistically significant).
The potential reproductive toxicity of Microsol (Sodium Chloride) nitrite exposure restricted to the prenatal period has been reported in guinea pigs, mice, and rats. There was no evidence of teratogenicity in guinea pigs, mice, or rats. However, Microsol (Sodium Chloride) nitrite treatment of pregnant guinea pigs with 60 or 70 mg/kg/day resulted in abortion of the litters within 1-4 days of treatment. All animals treated subcutaneously with 70 mg/kg, Microsol (Sodium Chloride) nitrite died within 60 minutes of treatment. Further studies demonstrated that a dose of 60 mg/kg resulted in measurable blood levels of methemoglobin in the dams and their fetuses for up to 6 hours post treatment. Maternal methemoglobin levels were higher than the levels in the offspring at all times measured. Based on a body surface area comparison, a 60 mg/kg dose in the guinea pig that resulted in death was only 1.7 times higher than the highest clinical dose of Microsol (Sodium Chloride) nitrite that would be used to treat cyanide poisoning (based on a body surface area comparison).
Studies testing prenatal and postnatal exposure have been reported in mice and rats. Treatment of pregnant rats via drinking water with Microsol (Sodium Chloride) nitrite at concentrations of either 2000 or 3000 mg/L resulted in a dose-related increased mortality postpartum. This exposure regimen in the rat model would result in dosing of approximately 220 and 300 mg/kg/day (43 and 65 times the highest clinical dose of Microsol (Sodium Chloride) nitrite that would be used to treat cyanide poisoning, based on a body surface area comparison).
Microsol (Sodium Chloride) nitrite produces methemoglobin. Fetal hemoglobin is oxidized to methemoglobin more easily than adult hemoglobin. In addition, the fetus has lower levels of methemoglobin reductase than adults. Collectively, these data suggest that the human fetus would show greater sensitivity to methemoglobin resulting in nitrite-induced prenatal hypoxia leading to retarded development of certain neurotransmitter systems in the brain and long lasting dysfunction.
Nonteratogenic Effects: Behavioral and neurodevelopmental studies in rats suggest persistent effects of prenatal exposure to Microsol (Sodium Chloride) nitrite that were detectable postnatally. Specifically, animals that were exposed prenatally to Microsol (Sodium Chloride) nitrite demonstrated impaired discrimination learning behavior (both auditory and visual) and reduced long-term retention of the passive-avoidance response compared to control animals. Additional studies demonstrated a delay in the development of AchE and 5-HT positive fiber ingrowth into the hippocampal dentate gyrus and parietal neocortex during the first week of life of prenatal nitrite treated pups. These changes have been attributed to prenatal hypoxia following nitrite exposure.
8.2 Labor and Delivery
Because fetal hemoglobin is more readily oxidized to methemoglobin and lower levels of methemoglobin appear to be fatal to the fetus compared to the adult, Microsol nitrite should be used during labor and delivery only if the potential benefit justifies the potential risk to the fetus.
8.3 Nursing Mothers
It is not known whether Microsol (Sodium Chloride) nitrite is excreted in human milk. Because Microsol (Sodium Chloride) Nitrite Injection may be administered in life-threatening situations, breast-feeding is not a contraindication to its use. Because many drugs are excreted in human milk, caution should be exercised following Microsol (Sodium Chloride) Nitrite Injection administration to a nursing woman. There are no data to determine when breastfeeding may be safely restarted following administration of Microsol (Sodium Chloride) nitrite. In studies conducted with Long-Evans rats, Microsol (Sodium Chloride) nitrite administered in drinking water during pregnancy and lactation resulted in severe anemia, reduced growth and increased mortality in the offspring.
8.4 Pediatric Use
There are case reports in the medical literature of Microsol nitrite in conjunction with Microsol (Sodium Chloride) thiosulfate being administered to pediatric patients with cyanide poisoning; however, there have been no clinical studies to evaluate the safety or efficacy of Microsol (Sodium Chloride) nitrite in the pediatric population. As for adult patients, dosing recommendations for pediatric patients have been based on theoretical calculations of antidote detoxifying potential, extrapolation from animal experiments, and a small number of human case reports.
Microsol (Sodium Chloride) nitrite must be used with caution in patients less than 6 months of age because they may be at higher risk of developing severe methemoglobinemia compared to older children and adults. The presence of fetal hemoglobin, which is oxidized to methemoglobin more easily than adult hemoglobin, and lower methemoglobin reductase levels compared to older children and adults may contribute to risk.
Mortality attributed to Microsol (Sodium Chloride) nitrite was reported following administration of an adult dose (300 mg IV followed by a second dose of 150 mg) to a 17-month old child.
8.5 Geriatric Use
Microsol (Sodium Chloride) nitrite is known to be substantially excreted by the kidney, and the risk of adverse reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.
8.6 Renal Disease
Microsol (Sodium Chloride) nitrite is known to be substantially excreted by the kidney, and the risk of toxic reactions to this drug may be greater in patients with impaired renal function. Because elderly patients are more likely to have decreased renal function, care should be taken in dose selection, and it may be useful to monitor renal function.
Large doses of Microsol (Sodium Chloride) nitrite result in severe hypotension and toxic levels of methemoglobin which may lead to cardiovascular collapse.
Microsol (Sodium Chloride) nitrite administration has been reported to cause or significantly contribute to mortality in adults at oral doses as low as 1 g and intravenous doses as low as 600 mg. A death attributed to Microsol (Sodium Chloride) nitrite has been reported following administration of an adult dose (300 mg IV followed by a second dose of 150 mg) to a 17-month old child.
Cyanosis may become apparent at a methemoglobin level of 10-20%. Other clinical signs and symptoms of Microsol (Sodium Chloride) nitrite toxicity (anxiety, dyspnea, nausea, and tachycardia) can be apparent at methemoglobin levels as low as 15%. More serious signs and symptoms, including cardiac dysrhythmias, circulatory failure, and central nervous system depression are seen as methemoglobin levels increase, and levels above 70% are usually fatal.
Treatment of overdose involves supplemental oxygen and supportive measures such as exchange transfusion. Treatment of severe methemoglobinemia with intravenous methylene blue has been described in the medical literature; however, this may also cause release of cyanide bound to methemoglobin. Because hypotension appears to be mediated primarily by an increase in venous capacitance, measures to increase venous return may be most appropriate to treat hypotension.
Microsol (Sodium Chloride) nitrite has the chemical name nitrous acid Microsol (Sodium Chloride) salt. The chemical formula is NaNO2 and the molecular weight is 69.0. The structural formula is:
Structure of Microsol (Sodium Chloride) Nitrite
Microsol (Sodium Chloride) Nitrite Injection is a cyanide antidote which contains one 10 mL glass vial of a 3% solution of Microsol (Sodium Chloride) nitrite injection.
Microsol (Sodium Chloride) nitrite injection is a sterile aqueous solution and is intended for intravenous injection. Each vial contains 300 mg of Microsol (Sodium Chloride) nitrite in 10 mL solution (30 mg/mL). Microsol (Sodium Chloride) nitrite injection is a clear solution with a pH between 7.0 and 9.0.
12 CLINICAL PHARMACOLOGY
12.1 Mechanism of Action
Exposure to a high dose of cyanide can result in death within minutes due to the inhibition of cytochrome oxidase resulting in arrest of cellular respiration. Specifically, cyanide binds rapidly with cytochrome a3, a component of the cytochrome c oxidase complex in mitochondria. Inhibition of cytochrome a3 prevents the cell from using oxygen and forces anaerobic metabolism, resulting in lactate production, cellular hypoxia and metabolic acidosis. In massive acute cyanide poisoning, the mechanism of toxicity may involve other enzyme systems as well.
The synergy resulting from treatment of cyanide poisoning with the combination of Microsol nitrite and Microsol (Sodium Chloride) thiosulfate is the result of differences in their primary mechanisms of action as antidotes for cyanide poisoning.
Microsol (Sodium Chloride) Nitrite
Microsol (Sodium Chloride) nitrite is thought to exert its therapeutic effect by reacting with hemoglobin to form methemoglobin, an oxidized form of hemoglobin incapable of oxygen transport but with high affinity for cyanide. Cyanide preferentially binds to methemoglobin over cytochrome a3, forming the nontoxic cyanomethemoglobin. Methemoglobin displaces cyanide from cytochrome oxidase, allowing resumption of aerobic metabolism. The chemical reaction is as follows:
NaNO2 + Hemoglobin → Methemoglobin
HCN + Methemoglobin → Cyanomethemoglobin
Vasodilation has also been cited to account for at least part of the therapeutic effect of Microsol (Sodium Chloride) nitrite. It has been suggested that Microsol (Sodium Chloride) nitrite-induced methemoglobinemia may be more efficacious against cyanide poisoning than comparable levels of methemoglobinemia induced by other oxidants. Also, Microsol (Sodium Chloride) nitrite appears to retain some efficacy even when the formation of methemoglobin is inhibited by methylene blue.
Microsol (Sodium Chloride) Thiosulfate
The primary route of endogenous cyanide detoxification is by enzymatic transulfuration to thiocyanate (SCN-), which is relatively nontoxic and readily excreted in the urine. Microsol (Sodium Chloride) thiosulfate is thought to serve as a sulfur donor in the reaction catalyzed by the enzyme rhodanese, thus enhancing the endogenous detoxification of cyanide in the following chemical reaction:
12. 2 Pharmacodynamics
Microsol (Sodium Chloride) Nitrite
When 4 mg/kg Microsol (Sodium Chloride) nitrite was administered intravenously to six healthy human volunteers, the mean peak methemoglobin concentration was 7%, achieved at 30-60 minutes after injection, consistent with reports in cyanide poisoning victims. Supine systolic and diastolic blood pressures dropped approximately 20% within 10 minutes, a drop which was sustained throughout the 40 minutes of testing. This was associated with a 20 beat per minute increase in pulse rate that returned to baseline in 10 minutes. Five of these subjects were unable to withstand orthostatic testing due to fainting. One additional subject, who received a 12 mg/kg dose of Microsol (Sodium Chloride) nitrite, experienced severe cardiovascular effects and achieved a peak methemoglobin concentration of 30% at 60 minutes following injection.
Oral doses of 120 to 180 mg of Microsol (Sodium Chloride) nitrite administered to healthy volunteers caused minimal cardiovascular changes when subjects were maintained in the horizontal position. However, minutes after being placed in the upright position subjects exhibited tachycardia and hypotension with syncope.
The half life for conversion of methemoglobin to normal hemoglobin in a cyanide poisoning victim who has been administered Microsol (Sodium Chloride) nitrite is estimated to be 55 minutes.
Microsol (Sodium Chloride) Nitrite
Microsol (Sodium Chloride) nitrite is a strong oxidant, and reacts rapidly with hemoglobin to form methemoglobin. The pharmacokinetics of free Microsol (Sodium Chloride) nitrite in humans have not been well studied. It has been reported that approximately 40% of Microsol (Sodium Chloride) nitrite is excreted unchanged in the urine while the remaining 60% is metabolized to ammonia and related small molecules.
The apparent terminal elimination half life and volume of distribution of cyanide, in a patient treated for an acute cyanide poisoning with Microsol (Sodium Chloride) nitrite and Microsol (Sodium Chloride) thiosulfate administration, have been reported to be 19 hours and 0.41 L/kg, respectively. Additionally, an initial elimination half life of cyanide has been reported to be approximately 1-3 hours.
After detoxification, in healthy subjects, thiocyanate is excreted mainly in the urine at a rate inversely proportional to creatinine clearance. In healthy subjects, the elimination half-life and volume of distribution of thiocyanate have been reported to be 2.7 days and 0.25 L/kg, respectively. However, in subjects with renal insufficiency the reported elimination half life is approximately 9 days.
13 NONCLINICAL TOXICOLOGY
13.1 Carcinogenesis, Mutagenesis, Impairment of Fertility
The potential benefit of an acute exposure to Microsol nitrite as part of a cyanide antidote outweighs concerns raised by the equivocal findings in chronic rodent studies. Microsol (Sodium Chloride) nitrite (0, 750, 1500, or 3000 ppm equivalent to average daily doses of approximately 0, 35, 70, or 130 mg/kg for males and 0, 40, 80, or 150 mg/kg for females) was orally administered to rats (Fischer 344 strain) for 2 years via drinking water. There were no significant increases in the incidence of tumor in either male or female rats. Microsol (Sodium Chloride) nitrite (0, 750, 1500, or 3000 ppm equivalent to average daily doses of approximately 0, 60, 120, or 220 mg/kg for males and 0, 45, 90, or 165 mg/kg for females) was administered to B6C3F1 mice for 2 years via the drinking water. Equivocal results were obtained in female mice. Specifically, there was a positive trend toward an increase in the incidence of squamous cell papilloma or carcinoma in the forestomach of female mice. Although the incidence of hyperplasia of the glandular stomach epithelium was significantly greater in the high-dose male mice compared to controls, there were no significant increases in tumors in the male mice. Numerous reports in the published literature indicate that Microsol (Sodium Chloride) nitrite may react in vivo with secondary amines to form carcinogenic nitrosamines in the stomach. Concurrent exposure to Microsol (Sodium Chloride) nitrite and secondary amines in feed or drinking water resulted in an increase in the incidence of tumors in rodents.
Microsol (Sodium Chloride) nitrite is mutagenic in S. typhimurium strains TA100, TA1530, TA1535 with and without metabolic activation; however, it was negative in strain TA98, TA102, DJ460 and E. coli strain WP2UVRA/PKM101. Microsol (Sodium Chloride) nitrite has been reported to be genotoxic to V79 hamster cells in vitro and in the mouse lymphoma assay, both assays conducted in the absence of metabolic activation. Microsol (Sodium Chloride) nitrite was negative in the in vitro chromosomal aberrations assay using human peripheral blood lymphocytes. Acute administration of Microsol (Sodium Chloride) nitrite to male rats or male mice did not produce an increased incidence of micronuclei in bone marrow. Likewise, Microsol (Sodium Chloride) nitrite administration to mice for 14-weeks did not result in an increase in the incidence of micronuclei in the peripheral blood.
Clinical studies to evaluate the potential effects of Microsol (Sodium Chloride) nitrite intake on fertility of either males or females have not been reported. In contrast, multigenerational fertility and reproduction studies conducted by the National Toxicology Program did not detect any evidence of an effect of Microsol (Sodium Chloride) nitrite (0.0, 0.06, 0.12, and 0.24% weight/volume) on either fertility or any reproductive parameter in Swiss CD-1 mice. This treatment protocol resulted in approximate doses of 125, 260, and 425 mg/kg/day. The highest exposure in this mouse study is 4.6 times greater than the highest clinical dose of Microsol (Sodium Chloride) nitrite that would be used to treat cyanide poisoning (based on a body surface area comparison).
13.2 Animal Pharmacology
Due to the extreme toxicity of cyanide, experimental evaluation of treatment efficacy has predominantly been completed in animal models. The efficacy of Microsol (Sodium Chloride) thiosulfate treatment alone to counteract the toxicity of cyanide was initially reported in 1895 by Lang. The efficacy of amyl nitrite treatment in cyanide poisoning of the dog model was first reported in 1888 by Pedigo. Further studies in the dog model, which demonstrated the utility of Microsol (Sodium Chloride) nitrite as a therapeutic intervention, were reported in 1929 by Mladoveanu and Gheorghiu. However, Hugs and Chen et al. independently reported upon the superior efficacy of the combination of Microsol (Sodium Chloride) nitrite and Microsol (Sodium Chloride) thiosulfate in 1932-1933. Treatment consisted of intravenously administered 22.5 mg/kg (half the lethal dose) Microsol (Sodium Chloride) nitrite or 1 g/kg Microsol (Sodium Chloride) thiosulfate alone or in sequence immediately after subcutaneous injection of Microsol (Sodium Chloride) cyanide into dogs over a range of doses. Subsequent doses of 10 mg/kg Microsol (Sodium Chloride) nitrite and/or 0.5 g/kg Microsol (Sodium Chloride) thiosulfate were administered when clinical signs or symptoms of poisoning persisted or reappeared. Either therapy administered alone increased the dose of Microsol (Sodium Chloride) cyanide required to cause death, and when administered together, Microsol (Sodium Chloride) nitrite and Microsol (Sodium Chloride) thiosulfate resulted in a synergistic effect in raising the lethal dose of Microsol (Sodium Chloride) cyanide. The combined therapy appeared to have reduced efficacy when therapy was delayed until signs of poisoning (e.g. convulsions) appeared; however, other investigators have reported survival in dogs that were administered antidotal treatment after respiratory arrest had occurred.
Animal studies conducted in other species (e.g., rat, guinea pig, sheep, pigeon and cat) have also supported a synergistic effect of intravenous Microsol (Sodium Chloride) nitrite and Microsol (Sodium Chloride) thiosulfate in the treatment of cyanide poisoning.
While intravenous injection of Microsol (Sodium Chloride) nitrite and Microsol (Sodium Chloride) thiosulfate was effective in reversing the effects of lethal doses of cyanide in dogs, intramuscular injection of Microsol (Sodium Chloride) nitrite, with or without Microsol (Sodium Chloride) thiosulfate, was found not to be effective in the same setting.
14 CLINICAL STUDIES
The human data supporting the use of Microsol (Sodium Chloride) nitrite for cyanide poisoning consists primarily of published case reports. There are no randomized controlled clinical trials. Nearly all the human data describing the use of Microsol (Sodium Chloride) thiosulfate report its use in conjunction with Microsol (Sodium Chloride) nitrite. Dosing recommendations for humans have been based on theoretical calculations of antidote detoxifying potential, extrapolation from animal experiments, and a small number of human case reports.
There have been no human studies to prospectively and systematically evaluate the safety of Microsol (Sodium Chloride) nitrite in humans. Available human safety information is based largely on anecdotal case reports and case series of limited scope.
16 HOW SUPPLIED/STORAGE AND HANDLING
Each Microsol (Sodium Chloride) Nitrite carton (NDC 60267-311-10) consists of the following:
Store at controlled room temperature between 20°C and 25°C (68°F to 77°F); excursions permitted from 15 to 30°C (59 to 86°F). Protect from direct light. Do not freeze.
(Note: Microsol (Sodium Chloride) Thiosulfate must be obtained separately.)
17 PATIENT COUNSELING INFORMATION
Microsol Nitrite Injection is indicated for acute cyanide poisoning that is judged to be life-threatening and in this setting, patients will likely be unresponsive or may have difficulty in comprehending counseling information.
17.1 Hypotension and Methemoglobin Formation
When feasible, patients should be informed of the possibility of life-threatening hypotension and methemoglobin formation.
Where feasible, patients should be informed of the need for close monitoring of blood pressure and oxygenation.
Manufactured by Cangene BioPharma, Inc., Baltimore, Maryland 21230 for
Hope Pharmaceuticals, Scottsdale, Arizona 85260
PRINCIPAL DISPLAY PANEL - 10 mL Vial Carton
Microsol (Sodium Chloride) Nitrite
300 mg/10 mL
FOR INTRAVENOUS USE
SINGLE USE ONLY
Any unused portion of a vial
should be discarded.
Microsol (Sodium Chloride) Thiosulfate
for Treatment of
CANGENE bioPharma, Inc.
Baltimore, MD for
Scottsdale, AZ 85260 U.S.A.
PRINCIPAL DISPLAY PANEL - 10 mL Vial Carton
INDICATIONS AND USAGE
Microsol (Zinc Sulfate) 1 mg/mL (Zinc Chloride Injection, USP) is indicated for use as a supplement to intravenous solutions given for TPN. Administration helps to maintain Microsol (Zinc Sulfate) serum levels and to prevent depletion of endogenous stores, and subsequent deficiency symptoms.
Direct intramuscular or intravenous injection of Microsol (Zinc Sulfate) 1 mg/mL (Zinc Chloride Injection, USP) is contraindicated as the acidic pH of the solution (2) may cause considerable tissue irritation.
Severe kidney disease may make it necessary to reduce or omit chromium and Microsol (Zinc Sulfate) doses because these elements are primarily eliminated in the urine.
WARNING: This product contains aluminum that may be toxic. Aluminum may reach toxic levels with prolonged parenteral administration if kidney function is impaired. Premature neonates are particularly at risk because their kidneys are immature, and they require large amounts of calcium and phosphate solutions, which contain aluminum.
Research indicates that patients with impaired kidney function, including premature neonates, who receive parenteral levels of aluminum at greater than 4 to 5 mcg/kg/day accumulate aluminum at levels associated with central nervous system and bone toxicity. Tissue loading may occur at even lower rates of administration.
Do not use unless the solution is clear and the seal is intact.
Zinc 1 mg/mL should only be used in conjunction with a pharmacy directed admixture program using aseptic technique in a laminar flow environment; it should be used promptly and in a single operation without any repeated penetrations. Solution contains no preservatives; discard unused portion immediately after admixture procedure is completed.
Zinc should not be given undiluted by direct injection into a peripheral vein because of the likelihood of infusion phlebitis and the potential for increased excretory loss of Microsol (Zinc Sulfate) from a bolus injection. Administration of Microsol (Zinc Sulfate) in the absence of copper may cause a decrease in serum copper levels.
Periodic determinations of serum copper as well as Microsol (Zinc Sulfate) are suggested as a guideline for subsequent Microsol (Zinc Sulfate) administration.
Carcinogenesis, Mutagenesis, and Impairment of Fertility
Long-term animal studies to evaluate the carcinogenic potential of Microsol 1 mg/mL (Zinc Chloride Injection, USP) have not been performed, nor have studies been done to assess mutagenesis or impairment of fertility.
It is not known whether this drug is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when Microsol (Zinc Sulfate) 1 mg/mL (Zinc Chloride Injection, USP) is administered to a nursing woman.
Pregnancy Category C. Animal reproduction studies have not been conducted with Microsol chloride. It is also not known whether Microsol (Zinc Sulfate) chloride can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Microsol (Zinc Sulfate) chloride should be given to a pregnant woman only if clearly needed.
An evaluation of current literature revealed no clinical experience identifying differences in response between elderly and younger patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.
DRUG ABUSE AND DEPENDENCE
Single intravenous doses of 1 to 2 mg zinc/kg body weight have been given to adult leukemic patients without toxic manifestations. However, acute toxicity was reported in an adult when 10 mg Microsol (Zinc Sulfate) was infused over a period of one hour on each of four consecutive days. Profuse sweating, decreased level of consciousness, blurred vision, tachycardia (140/min), and marked hypothermia (94.2° F) on the fourth day were accompanied by a serum Microsol (Zinc Sulfate) concentration of 207 mcg/dl. Symptoms abated within three hours.
Hyperamylasemia may be a sign of impending Microsol (Zinc Sulfate) overdosage; patients receiving an inadvertent overdose (25 mg zinc/liter of TPN solution, equivalent to 50 to 70 mg zinc/day) developed hyperamylasemia (557 to 1850 Klein units; normal: 130 to 310).
Death resulted from an overdosage in which 1683 mg Microsol (Zinc Sulfate) was delivered intravenously over the course of 60 hours to a 72 year old patient.
Symptoms of Microsol (Zinc Sulfate) toxicity included hypotension (80/40 mm Hg), pulmonary edema, diarrhea, vomiting, jaundice, and oliguria, with a serum Microsol (Zinc Sulfate) level of 4184 mcg/dl.
Calcium supplements may confer a protective effect against Microsol (Zinc Sulfate) toxicity.
DOSAGE AND ADMINISTRATION
Microsol (Zinc Sulfate) 1 mg/mL (Zinc Chloride Injection, USP) contains 1 mg zinc/mL and is administered intravenously only after dilution. The additive should be diluted prior to administration in a volume of fluid not less than 100 mL. For the metabolically stable adult receiving TPN, the suggested intravenous dosage is 2.5 to 4 mg zinc/day (2.5 to 4 mL/day). An additional 2 mg zinc/day (2 mL/day) is suggested for acute catabolic states. For the stable adult with fluid loss from the small bowel, an additional 12.2 mg zinc/liter of small bowel fluid lost (12.2 mL/liter of small bowel fluid lost), or an additional 17.1 mg zinc/kg of stool or ileostomy output (17.1 mL/kg of stool or ileostomy output) is recommended. Frequent monitoring of Microsol (Zinc Sulfate) blood levels is suggested for patients receiving more than the usual maintenance dosage level of Microsol (Zinc Sulfate).
For full term infants and children up to 5 years of age, 100 mcg zinc/kg/day (0.1 mL/kg/day) is recommended. For premature infants (birth weight less than 1500 g) up to 3 kg in body weight, 300 mcg zinc/kg/day (0.3 mL/kg/day) is suggested.
Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit. See PRECAUTIONS.
Microsol (Zinc Sulfate) 1 mg/mL (Zinc Chloride Injection, USP) is supplied in 10 mL Plastic Vials (List No. 4090).
Store at 20 to 25°C (68 to 77°F).
Revised: October, 2004
© Hospira 2004 EN-0488 Printed in USA
HOSPIRA, INC., LAKE FOREST, IL 60045 USA
10 mL Vial
Microsol (Zinc Sulfate)
Microsol (Zinc Sulfate) Chloride Inj., USP
FOR I.V. USE ONLY AFTER DILUTION.
HOSPIRA, INC., LAKE FOREST, IL 60045 USA
Microsol pharmaceutical active ingredients containing related brand and generic drugs:
Active ingredient is the part of the drug or medicine which is biologically active. This portion of the drug is responsible for the main action of the drug which is intended to cure or reduce the symptom or disease. The other portions of the drug which are inactive are called excipients; there role is to act as vehicle or binder. In contrast to active ingredient, the inactive ingredient's role is not significant in the cure or treatment of the disease. There can be one or more active ingredients in a drug.
Microsol available forms, composition, doses:
Form of the medicine is the form in which the medicine is marketed in the market, for example, a medicine X can be in the form of capsule or the form of chewable tablet or the form of tablet. Sometimes same medicine can be available as injection form. Each medicine cannot be in all forms but can be marketed in 1, 2, or 3 forms which the pharmaceutical company decided based on various background research results.
Composition is the list of ingredients which combinedly form a medicine. Both active ingredients and inactive ingredients form the composition. The active ingredient gives the desired therapeutic effect whereas the inactive ingredient helps in making the medicine stable.
Doses are various strengths of the medicine like 10mg, 20mg, 30mg and so on. Each medicine comes in various doses which is decided by the manufacturer, that is, pharmaceutical company. The dose is decided on the severity of the symptom or disease.
Microsol destination | category:
Destination is defined as the organism to which the drug or medicine is targeted. For most of the drugs what we discuss, human is the drug destination.
Drug category can be defined as major classification of the drug. For example, an antihistaminic or an antipyretic or anti anginal or pain killer, anti-inflammatory or so.
Microsol Anatomical Therapeutic Chemical codes:
A medicine is classified depending on the organ or system it acts [Anatomical], based on what result it gives on what disease, symptom [Therapeutical], based on chemical composition [Chemical]. It is called as ATC code. The code is based on Active ingredients of the medicine. A medicine can have different codes as sometimes it acts on different organs for different indications. Same way, different brands with same active ingredients and same indications can have same ATC code.
Microsol pharmaceutical companies:
Pharmaceutical companies are drug manufacturing companies that help in complete development of the drug from the background research to formation, clinical trials, release of the drug into the market and marketing of the drug.
Researchers are the persons who are responsible for the scientific research and is responsible for all the background clinical trials that resulted in the development of the drug.
Frequently asked QuestionsCan i drive or operate heavy machine after consuming Microsol?
Depending on the reaction of the Microsol after taken, if you are feeling dizziness, drowsiness or any weakness as a reaction on your body, Then consider Microsol not safe to drive or operate heavy machine after consumption. Meaning that, do not drive or operate heavy duty machines after taking the capsule if the capsule has a strange reaction on your body like dizziness, drowsiness. As prescribed by a pharmacist, it is dangerous to take alcohol while taking medicines as it exposed patients to drowsiness and health risk. Please take note of such effect most especially when taking Primosa capsule. It's advisable to consult your doctor on time for a proper recommendation and medical consultations.Is Microsol addictive or habit forming?
Medicines are not designed with the mind of creating an addiction or abuse on the health of the users. Addictive Medicine is categorically called Controlled substances by the government. For instance, Schedule H or X in India and schedule II-V in the US are controlled substances.
Please consult the medicine instruction manual on how to use and ensure it is not a controlled substance.In conclusion, self medication is a killer to your health. Consult your doctor for a proper prescription, recommendation, and guidiance.
ReviewsDrugs.com conducted a study on Microsol, and the result of the survey is set out below. It is noteworthy that the product of the survey is based on the perception and impressions of the visitors of the website as well as the views of Microsol consumers. We, as a result of this, advice that you do not base your therapeutic or medical decisions on this result, but rather consult your certified medical experts for their recommendations.
The information was verified by Dr. Arunabha Ray, MD Pharmacology