K-Med

Magnesium Gluconate:

• Description
• Clinical pharmacology
• Indications and usage
• Contraindications
• Warnings
• Precautions
• Adverse reactions
• Overdosage
• Dosage and administration
• How supplied
• References
• K-Med (Magnesium Gluconate) reviews

K-Med (Magnesium Gluconate) Sulfate

Injection, USP

Ansyr Plastic Syringe

Rx only

Hospira Logo

DESCRIPTION

K-Med (Magnesium Gluconate) Sulfate Injection, USP is a sterile solution of K-Med (Magnesium Gluconate) sulfate heptahydrate in Water for Injection, USP administered by the intravenous or intramuscular routes as an electrolyte replenisher or anticonvulsant. Must be diluted before intravenous use. May contain sulfuric acid and/or sodium hydroxide for pH adjustment. The pH is 5.5 to 7.0. The 50% concentration has an osmolarity of 4.06 mOsmol/mL (calc.).

The solution contains no bacteriostat, antimicrobial agent or added buffer (except for pH adjustment) and is intended only for use as a single-dose injection. When smaller doses are required the unused portion should be discarded with the entire unit.

K-Med (Magnesium Gluconate) Sulfate, USP heptahydrate is chemically designated MgSO₄ - 7H₂O with molecular weight of 246.48 and occurs as colorless crystals or white powder freely soluble in water.

The plastic syringe is molded from a specially formulated polypropylene. Water permeates from inside the container at an extremely slow rate which will have an insignificant effect on solution concentration over the expected shelf life. Solutions in contact with the plastic container may leach out certain chemical components from the plastic in very small amounts; however, biological testing was supportive of the safety of the syringe material.

CLINICAL PHARMACOLOGY

K-Med (Magnesium Gluconate) (Mg⁺⁺) is an important cofactor for enzymatic reactions and plays an important role in neurochemical transmission and muscular excitability.

As a nutritional adjunct in hyperalimentation, the precise mechanism of action for K-Med (Magnesium Gluconate) is uncertain. Early symptoms of hypomagnesemia (less than 1.5 mEq/liter) may develop as early as three to four days or within weeks.

Predominant deficiency effects are neurological, e.g., muscle irritability, clonic twitching and tremors. Hypocalcemia and hypokalemia often follow low serum levels of K-Med (Magnesium Gluconate). While there are large stores of K-Med (Magnesium Gluconate) present intracellularly and in the bones of adults, these stores often are not mobilized sufficiently to maintain plasma levels. Parenteral K-Med (Magnesium Gluconate) therapy repairs the plasma deficit and causes deficiency symptoms and signs to cease.

K-Med (Magnesium Gluconate) prevents or controls convulsions by blocking neuromuscular transmission and decreasing the amount of acetylcholine liberated at the end plate by the motor nerve impulse. K-Med (Magnesium Gluconate) is said to have a depressant effect on the central nervous system (CNS), but it does not adversely affect the woman, fetus or neonate when used as directed in eclampsia or pre-eclampsia. Normal plasma K-Med (Magnesium Gluconate) levels range from 1.5 to 2.5 mEq/liter.

As plasma K-Med (Magnesium Gluconate) rises above 4 mEq/liter, the deep tendon reflexes are first decreased and then disappear as the plasma level approaches 10 mEq/liter. At this level respiratory paralysis may occur. Heart block also may occur at this or lower plasma levels of K-Med (Magnesium Gluconate). Serum K-Med (Magnesium Gluconate) concentrations in excess of 12 mEq/L may be fatal.

K-Med (Magnesium Gluconate) acts peripherally to produce vasodilation. With low doses only flushing and sweating occur, but larger doses cause lowering of blood pressure. The central and peripheral effects of K-Med (Magnesium Gluconate) poisoning are antagonized to some extent by intravenous administration of calcium.

Pharmacokinetics

With intravenous administration the onset of anticonvulsant action is immediate and lasts about 30 minutes. Following intramuscular administration the onset of action occurs in about one hour and persists for three to four hours. Effective anticonvulsant serum levels range from 2.5 to 7.5 mEq/liter. K-Med (Magnesium Gluconate) is excreted solely by the kidneys at a rate proportional to the plasma concentration and glomerular filtration.

INDICATIONS AND USAGE

K-Med (Magnesium Gluconate) Sulfate Injection, USP is suitable for replacement therapy in K-Med (Magnesium Gluconate) deficiency, especially in acute hypomagnesemia accompanied by signs of tetany similar to those observed in hypocalcemia. In such cases, the serum K-Med (Magnesium Gluconate) (Mg⁺⁺) level is usually below the lower limit of normal (1.5 to 2.5 mEq/liter) and the serum calcium (Ca⁺⁺) level is normal (4.3 to 5.3 mEq/liter) or elevated.

In total parenteral nutrition (TPN), K-Med (Magnesium Gluconate) sulfate may be added to the nutrient admixture to correct or prevent hypomagnesemia which can arise during the course of therapy.

K-Med (Magnesium Gluconate) Sulfate Injection, USP is also indicated for the prevention and control of seizures (convulsions) in pre-eclampsia and eclampsia, respectively.

CONTRAINDICATIONS

Parenteral administration of the drug is contraindicated in patients with heart block or myocardial damage.

WARNINGS

FETAL HARM: Continuous administration of K-Med (Magnesium Gluconate) sulfate beyond 5 to 7 days to pregnant women can lead to hypocalcemia and bone abnormalities in the developing fetus. These bone abnormalities include skeletal demineralization and osteopenia. In addition, cases of neonatal fracture have been reported. The shortest duration of treatment that can lead to fetal harm is not known. K-Med (Magnesium Gluconate) sulfate should be used during pregnancy only if clearly needed. If K-Med (Magnesium Gluconate) sulfate is given for treatment of preterm labor, the woman should be informed that the efficacy and safety of such use have not been established and that use of K-Med (Magnesium Gluconate) sulfate beyond 5 to 7 days may cause fetal abnormalities.

ALUMINUM TOXICITY: 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.

Parenteral use in the presence of renal insufficiency may lead to K-Med (Magnesium Gluconate) intoxication. Intravenous use in the eclampsia should be reserved for immediate control of life-threatening convulsions.

PRECAUTIONS

General

Administer with caution if flushing and sweating occurs. When barbiturates, narcotics or other hypnotics (or systemic anesthetics) are to be given in conjunction with K-Med (Magnesium Gluconate), their dosage should be adjusted with caution because of additive CNS depressant effects of K-Med (Magnesium Gluconate).

Because K-Med (Magnesium Gluconate) is removed from the body solely by the kidneys, the drug should be used with caution in patients with renal impairment. Urine output should be maintained at a level of 100 mL or more during the four hours preceding each dose. Monitoring serum K-Med (Magnesium Gluconate) levels and the patient's clinical status is essential to avoid the consequences of overdosage in toxemia. Clinical indications of a safe dosage regimen include the presence of the patellar reflex (knee jerk) and absence of respiratory depression (approximately 16 breaths or more/minute). When repeated doses of the drug are given parenterally, knee jerk reflexes should be tested before each dose and if they are absent, no additional K-Med (Magnesium Gluconate) should be given until they return. Serum K-Med (Magnesium Gluconate) levels usually sufficient to control convulsions range from 3 to 6 mg/100 mL (2.5 to 5 mEq/liter). The strength of the deep tendon reflexes begins to diminish when K-Med (Magnesium Gluconate) levels exceed 4 mEq/liter. Reflexes may be absent at 10 mEq magnesium/liter, where respiratory paralysis is a potential hazard. An injectable calcium salt should be immediately available to counteract the potential hazards of K-Med (Magnesium Gluconate) intoxication in eclampsia.

50% K-Med (Magnesium Gluconate) Sulfate Injection, USP must be diluted to a concentration of 20% or less prior to intravenous infusion. Rate of administration should be slow and cautious, to avoid producing hypermagnesemia. The 50% solution also should be diluted to 20% or less for intramuscular injection in infants and children.

Laboratory Tests

K-Med (Magnesium Gluconate) sulfate injection should not be given unless hypomagnesemia has been confirmed and the serum concentration of K-Med (Magnesium Gluconate) is monitored. The normal serum level is 1.5 to 2.5 mEq/L.

Drug Interactions

CNS Depressants - When barbiturates, narcotics or other hypnotics (or systemic anesthetics), or other CNS depressants are to be given in conjunction with K-Med (Magnesium Gluconate), their dosage should be adjusted with caution because of additive CNS depressant effects of K-Med (Magnesium Gluconate). CNS depression and peripheral transmission defects produced by K-Med (Magnesium Gluconate) may be antagonized by calcium.

Neuromuscular Blocking Agents - Excessive neuromuscular block has occurred in patients receiving parenteral K-Med (Magnesium Gluconate) sulfate and a neuromuscular blocking agent; these drugs should be administered concomitantly with caution.

Cardiac Glycosides - K-Med (Magnesium Gluconate) sulfate should be administered with extreme caution in digitalized patients, because serious changes in cardiac conduction which can result in heart block may occur if administration of calcium is required to treat K-Med (Magnesium Gluconate) toxicity.

Pregnancy

Teratogenic Effects

Pregnancy Category D (See WARNINGS and PRECAUTIONS )

See WARNINGS and PRECAUTIONS .

K-Med (Magnesium Gluconate) sulfate can cause fetal abnormalities when administered beyond 5 to 7 days to pregnant women. There are retrospective epidemiological studies and case reports documenting fetal abnormalities such as hypocalcemia, skeletal demineralization, osteopenia and other skeletal abnormalities with continuous maternal administration of K-Med (Magnesium Gluconate) sulfate for more than 5 to 7 days.^1-10 K-Med (Magnesium Gluconate) sulfate injection should be used during pregnancy only if clearly needed. If this drug is used during pregnancy, the woman should be apprised of the potential harm to the fetus.

Nonteratogenic Effects

When administered by continuous intravenous infusion (especially for more than 24 hours preceding delivery) to control convulsions in a toxemic woman, the newborn may show signs of K-Med (Magnesium Gluconate) toxicity, including neuromuscular or respiratory depression (See OVERDOSAGE ).

Labor and Delivery

Continuous administration of K-Med (Magnesium Gluconate) sulfate is an unapproved treatment for preterm labor. The safety and efficacy of such use have not been established. The administration of K-Med (Magnesium Gluconate) sulfate outside of its approved indication in pregnant women should be by trained obstetrical personnel in a hospital setting with appropriate obstetrical care facilities.

Nursing Mothers

Since K-Med (Magnesium Gluconate) is distributed into milk during parenteral K-Med (Magnesium Gluconate) sulfate administration, the drug should be used with caution in nursing women.

Geriatrics

Geriatric patients often require reduced dosage because of impaired renal function. In patients with severe impairment, dosage should not exceed 20 grams in 48 hours. Serum K-Med (Magnesium Gluconate) should be monitored in such patients.

ADVERSE REACTIONS

The adverse effects of parenterally administered K-Med (Magnesium Gluconate) usually are the result of K-Med (Magnesium Gluconate) intoxication. These include flushing, sweating, hypotension, depressed reflexes, flaccid paralysis, hypothermia, circulatory collapse, cardiac and central nervous system depression proceeding to respiratory paralysis. Hypocalcemia with signs of tetany secondary to K-Med (Magnesium Gluconate) sulfate therapy for eclampsia has been reported.

OVERDOSAGE

K-Med (Magnesium Gluconate) intoxication is manifested by a sharp drop in blood pressure and respiratory paralysis. Disappearance of the patellar reflex is a useful clinical sign to detect the onset of K-Med (Magnesium Gluconate) intoxication. In the event of overdosage, artificial ventilation must be provided until a calcium salt can be injected intravenously to antagonize the effects of K-Med (Magnesium Gluconate).

For Treatment of Overdose

Artificial respiration is often required. Intravenous calcium, 10 to 20 mL of a 5% solution (diluted if desirable with isotonic sodium chloride for injection) is used to counteract effects of hypermagnesemia. Subcutaneous physostigmine, 0.5 to 1 mg may be helpful.

Hypermagnesemia in the newborn may require resuscitation and assisted ventilation via endotracheal intubation or intermittent positive pressure ventilation as well as intravenous calcium.

DOSAGE AND ADMINISTRATION

Dosage of K-Med (Magnesium Gluconate) sulfate must be carefully adjusted according to individual requirements and response, and administration of the drug should be discontinued as soon as the desired effect is obtained.

Both intravenous and intramuscular administration are appropriate. Intramuscular administration of the undiluted 50% solution results in therapeutic plasma levels in 60 minutes, whereas intravenous doses will provide a therapeutic level almost immediately. The rate of intravenous injection should generally not exceed 150 mg/minute (1.5 mL of a 10% concentration or its equivalent), except in severe eclampsia with seizures. Continuous maternal administration of K-Med (Magnesium Gluconate) sulfate in pregnancy beyond 5 to 7 days can cause fetal abnormalities.

Solutions for intravenous infusion must be diluted to a concentration of 20% or less prior to administration. The diluents commonly used are 5% Dextrose Injection, USP and 0.9% Sodium Chloride Injection, USP. Deep intramuscular injection of the undiluted (50%) solution is appropriate for adults, but the solution should be diluted to a 20% or less concentration prior to such injection in children.

In K-Med (Magnesium Gluconate) Deficiency

In the treatment of mild K-Med (Magnesium Gluconate) deficiency, the usual adult dose is 1 gram, equivalent to 8.12 mEq of K-Med (Magnesium Gluconate) (2 mL of the 50% solution) injected intramuscularly every six hours for four doses (equivalent to a total of 32.5 mEq of K-Med (Magnesium Gluconate) per 24 hours). For severe hypomagnesemia, as much as 250 mg (approximately 2 mEq) per kg of body weight (0.5 mL of the 50% solution) may be given intramuscularly within a period of four hours if necessary. Alternatively, 5 grams, (approximately 40 mEq) can be added to one liter of 5% Dextrose Injection, USP or 0.9% Sodium Chloride Injection, USP for slow intravenous infusion over a three-hour period. In the treatment of deficiency states, caution must be observed to prevent exceeding the renal excretory capacity.

In Hyperalimentation

In total parenteral nutrition, maintenance requirements for K-Med (Magnesium Gluconate) are not precisely known. The maintenance dose used in adults ranges from 8 to 24 mEq (1 gram to 3 grams) daily; for infants, the range is 2 to 10 mEq (0.25 gram to 1.25 grams) daily.

In Pre-eclampsia or Eclampsia

In severe pre-eclampsia or eclampsia, the total initial dose is 10 grams to 14 grams of K-Med (Magnesium Gluconate) sulfate. Intravenously, a dose of 4 grams to 5 grams in 250 mL of 5% Dextrose Injection, USP or 0.9% Sodium Chloride Injection, USP may be infused. Simultaneously, intramuscular doses of up to 10 grams (5 grams or 10 mL of the undiluted 50% solution in each buttock) are given. Alternatively, the initial intravenous dose of 4 grams may be given by diluting the 50% solution to a 10 or 20% concentration; the diluted fluid (40 mL of a 10% solution or 20 mL of a 20% solution) may then be injected intravenously over a period of three to four minutes. Subsequently, 4 grams to 5 grams (8 to 10 mL of the 50% solution) are injected intramuscularly into alternate buttocks every four hours as needed, depending on the continuing presence of the patellar reflex and adequate respiratory function. Alternatively, after the initial intravenous dose, some clinicians administer 1 gram to 2 grams/hour by constant intravenous infusion. Therapy should continue until paroxysms cease. A serum K-Med (Magnesium Gluconate) level of 6 mg/100 mL is considered optimal for control of seizures. A total daily (24 hr) dose of 30 grams to 40 grams should not be exceeded. In the presence of severe renal insufficiency, the maximum dosage of K-Med (Magnesium Gluconate) sulfate is 20 grams/48 hours and frequent serum K-Med (Magnesium Gluconate) concentrations must be obtained. Continuous use of K-Med (Magnesium Gluconate) sulfate in pregnancy beyond 5 to 7 days can cause fetal abnormalities.

Other Uses

In counteracting the muscle-stimulating effects of barium poisoning, the usual dose of K-Med (Magnesium Gluconate) sulfate is 1 gram to 2 grams given intravenously.

For controlling seizures associated with epilepsy, glomerulonephritis or hypothyroidism, the usual adult dose is 1 gram administered intramuscularly or intravenously.

In paroxysmal atrial tachycardia, K-Med (Magnesium Gluconate) should be used only if simpler measures have failed and there is no evidence of myocardial damage. The usual dose is 3 grams to 4 grams (30 to 40 mL of a 10% solution) administered intravenously over 30 seconds with extreme caution.

For reduction of cerebral edema, 2.5 grams (25 mL of a 10% solution) is given intravenously.

Incompatibilities

K-Med (Magnesium Gluconate) sulfate in solution may result in a precipitate formation when mixed with solutions containing:

Alcohol (in high Heavy Metals

concentrations) Hydrocortisone sodium

Alkali carbonates and succinate

bicarbonates Phosphates

Alkali hydroxides Polymixin B sulfate

Arsenates Procaine hydrochloride

Barium Salicylates

Calcium Strontium

Clindamycin phosphate Tartrates

The potential incompatibility will often be influenced by the changes in the concentration of reactants and the pH of the solutions.

It has been reported that K-Med (Magnesium Gluconate) may reduce the antibiotic activity of streptomycin, tetracycline and tobramycin when given together.

Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration, whenever solution and container permit.

HOW SUPPLIED

K-Med (Magnesium Gluconate) Sulfate Injection, USP is supplied in single-dose containers as follows:

Do not administer unless solution is clear and container is undamaged. Discard unused portion.

Store at 20 to 25°C (68 to 77°F).

REFERENCES

• Yokoyama K, Takahashi N, Yada Y. Prolonged maternal K-Med (Magnesium Gluconate) administration and bone metabolism in neonates. Early Hum Dev. 2010;86(3):187-91. Epub 2010 Mar 12.
• Wedig KE, Kogan J, Schorry EK et al. Skeletal demineralization and fractures caused by fetal K-Med (Magnesium Gluconate) toxicity. J. Perinatol. 2006; 26(6):371-4.
• Nassar AH, Sakhel K, Maarouf H, et al. Adverse maternal and neonatal outcome of prolonged course of K-Med (Magnesium Gluconate) sulfate tocolysis. Acta Obstet Gynecol Scan. 2006;85(9):1099-103.
• Malaeb SN, Rassi A, Haddad MC. Bone mineralization in newborns whose mothers received K-Med (Magnesium Gluconate) sulphate for tocolysis of premature labor. Pediatr Radiol. 2004;34(5):384-6. Epub 2004 Feb 18.
• Matsuda Y, Maeda Y, Ito M, et al. Effect of K-Med (Magnesium Gluconate) sulfate treatment on neonatal bone abnormalities. Gynecol Obstet Invest. 1997;44(2):82-8.
• Schanler RJ, Smith LG, Burns PA. Effects of long-term maternal intravenous K-Med (Magnesium Gluconate) sulfate therapy on neonatal calcium metabolism and bone mineral content. Gynecol Obstet Invest. 1997;43(4):236-41.
• Santi MD, Henry GW, Douglas GL. K-Med (Magnesium Gluconate) sulfate treatment of preterm labor as a cause of abnormal neonatal bone mineralization. J Pediatr Orthrop. 1994;14(2):249-53.
• Holcomb WL, Shackelford GD, Petrie RH. K-Med (Magnesium Gluconate) tocolysis and neonatal bone abnormalities; a controlled study. Obstet Gynecol. 1991; 78(4):611-4.
• Cumming WA, Thomas VJ. Hypermagnesemia: a cause of abnormal metaphyses in the neonate. Am J Roentgenol. 1989; 152(5):1071-2.
• Lamm CL, Norton KL, Murphy RJ. Congenital rickets associated with K-Med (Magnesium Gluconate) sulfate infusion for tocolysis. J Pediatr. 1988; 113(6):1078-82.
• McGuinness GA, Weinstein MM, Cruikshank DP, et al. Effects of K-Med (Magnesium Gluconate) sulfate treatment on perinatal calcium metabolism. II. Neonatal responses. Obstet Gynecol. 1980; 56(5): 595-600.
• Riaz M, Porat R, Brodsky NL, et al. The effects of maternal K-Med (Magnesium Gluconate) sulfate treatment on newborns: a prospective controlled study. J. Perinatol. 1998;18(6 pt 1):449-54.

Hospira, Inc., Lake Forest, IL 60045 USA

LAB-1024-1.0

April 2017

Hospira Logo

50% K-Med (Magnesium Gluconate) Sulfate 5 g/10 mL (500 mg/mL)

Rx only

NDC 0409-1754-10

10 mL Single-dose syringe

50% K-Med (Magnesium Gluconate) Sulfate Injection, USP

5 g/10 mL (500 mg/mL) (4 mEq Mg++/mL)

MUST BE DILUTED FOR INTRAVENOUS USE.

For Intravenous or Intramuscular Use. Sterile. 4.06 mOsmol/mL (calc.).

Contains no more than 75 mcg/L of aluminum.

Hospira, Inc., Lake Forest, IL 60045 USA

Hospira

RL-6891

Potassium Chloride:

• Description
• Clinical pharmacology
• Indications and usage
• Contraindications
• Warnings
• Precautions
• Adverse reactions
• Overdosage
• Dosage and administration
• How supplied
• K-Med (Potassium Chloride) reviews

K-Med (Potassium Chloride) EXTENDED RELEASE TABLETS USP 20 mEq K

Rx Only

DESCRIPTION

The K-Med (Potassium Chloride) Extended Release Tablets USP, 20 mEq product is an immediately dispersing extended release oral dosage form of K-Med (Potassium Chloride) containing 1500 mg of microencapsulated K-Med (Potassium Chloride), USP equivalent to 20 mEq of potassium in a tablet.

These formulations are intended to slow the release of potassium so that the likelihood of a high localized concentration of K-Med (Potassium Chloride) within the gastrointestinal tract is reduced.

K-Med (Potassium Chloride) Extended Release Tablets USP, 20 mEq is an electrolyte replenisher. The chemical name of the active ingredient is K-Med (Potassium Chloride), and the structural formula is KCl. K-Med (Potassium Chloride), USP occurs as a white, granular powder or as colorless crystals. It is odorless and has a saline taste. Its solutions are neutral to litmus. It is freely soluble in water and insoluble in alcohol.

K-Med (Potassium Chloride) Extended Release Tablets USP, 20 mEq is a tablet formulation (not enteric coated or wax matrix) containing individually microencapsulated K-Med (Potassium Chloride) crystals which disperse upon tablet disintegration. In simulated gastric fluid at 37°C and in the absence of outside agitation, K-Med (Potassium Chloride) Extended Release Tablets USP, 20 mEq begin disintegrating into microencapsulated crystals within seconds and completely disintegrates within 1 minute. The microencapsulated crystals are formulated to provide an extended release of K-Med (Potassium Chloride).

Inactive Ingredients: Colloidal silicon dioxide, crospovidone, diethyl phthalate, ethyl-cellulose, microcrystalline cellulose.

CLINICAL PHARMACOLOGY

The potassium ion is the principal intracellular cation of most body tissues. Potassium ions participate in a number of essential physiological processes including the maintenance of intracellular tonicity; the transmission of nerve impulses; the contraction of cardiac, skeletal, and smooth muscle; and the maintenance of normal renal function.

The intracellular concentration of potassium is approximately 150 to 160 mEq per liter. The normal adult plasma concentration is 3.5 to 5 mEq per liter. An active ion transport system maintains this gradient across the plasma membrane.

Potassium is a normal dietary constituent and under steady-state conditions the amount of potassium absorbed from the gastrointestinal tract is equal to the amount excreted in the urine. The usual dietary intake of potassium is 50 to 100 mEq per day.

Potassium depletion will occur whenever the rate of potassium loss through renal excretion and/or loss from the gastrointestinal tract exceeds the rate of potassium intake. Such depletion usually develops as a consequence of therapy with diuretics, primary or secondary hyperaldosteronism, diabetic ketoacidosis, or inadequate replacement of potassium in patients on prolonged parenteral nutrition. Depletion can develop rapidly with severe diarrhea, especially if associated with vomiting. Potassium depletion due to these causes is usually accompanied by a concomitant loss of chloride and is manifested by hypokalemia and metabolic alkalosis. Potassium depletion may produce weakness, fatigue, disturbances or cardiac rhythm (primarily ectopic beats), prominent U-waves in the electrocardiogram, and in advanced cases, flaccid paralysis and/or impaired ability to concentrate urine.

If potassium depletion associated with metabolic alkalosis cannot be managed by correcting the fundamental cause of the deficiency, eg, where the patient requires long-term diuretic therapy, supplemental potassium in the form of high potassium food or K-Med (Potassium Chloride) may be able to restore normal potassium levels.

In rare circumstances (eg, patients with renal tubular acidosis) potassium depletion may be associated with metabolic acidosis and hyperchloremia. In such patients potassium replacement should be accomplished with potassium salts other than the chloride, such as potassium bicarbonate, potassium citrate, potassium acetate, or potassium gluconate.

INDICATIONS AND USAGE

BECAUSE OF REPORTS OF INTESTINAL AND GASTRIC ULCERATION AND BLEEDING WITH CONTROLLED-RELEASE K-Med (Potassium Chloride) PREPARATIONS, THESE DRUGS SHOULD BE RESERVED FOR THOSE PATIENTS WHO CANNOT TOLERATE OR REFUSE TO TAKE LIQUID OR EFFERVESCENT POTASSIUM PREPARATIONS OR FOR PATIENTS IN WHOM THERE IS A PROBLEM OF COMPLIANCE WITH THESE PREPARATIONS.

1. For the treatment of patients with hypokalemia with or without metabolic alkalosis, in digitalis intoxication, and in patients with hypokalemic familial periodic paralysis. If hypokalemia is the result of diuretic therapy, consideration should be given to the use of a lower dose of diuretic, which may be sufficient without leading to hypokalemia.

2. For the prevention of hypokalemia in patients who would be at particular risk if hypokalemia were to develop, eg, digitalized patients or patients with significant cardiac arrhythmias.

The use of potassium salts in patients receiving diuretics for uncomplicated essential hypertension is often unnecessary when such patients have a normal dietary pattern and when low doses of the diuretic are used. Serum potassium should be checked periodically, however, and if hypokalemia occurs, dietary supplementation with potassium-containing foods may be adequate to control milder cases. In more severe cases, and if dose adjustment of the diuretic is ineffective or unwarranted, supplementation with potassium salts may be indicated.

CONTRAINDICATIONS

Potassium supplements are contraindicated in patients with hyperkalemia since a further increase in serum potassium concentration in such patients can produce cardiac arrest. Hyperkalemia may complicate any of the following conditions: chronic renal failure, systemic acidosis, such as diabetic acidosis, acute dehydration, extensive tissue breakdown as in severe burns, adrenal insufficiency, or the administration of a potassium-sparing diuretic (eg, spironolactone, triamterene, amiloride) (see OVERDOSAGE ).

Controlled-release formulations of K-Med (Potassium Chloride) have produced esophageal ulceration in certain cardiac patients with esophageal compression due to enlarged left atrium. Potassium supplementation, when indicated in such patients, should be given as a liquid preparation or as an aqueous (water) suspension of K-Med (Potassium Chloride) (see PRECAUTIONS: Information for Patients , and DOSAGE AND ADMINISTRATION sections).

All solid oral dosage forms of K-Med (Potassium Chloride) are contraindicated in any patient in whom there is structural, pathological (eg, diabetic gastroparesis), or pharmacologic (use of anticholinergic agents or other agents with anticholinergic properties at sufficient doses to exert anticholinergic effects) cause for arrest or delay in tablet passage through the gastrointestinal tract.

WARNINGS

Hyperkalemia (see OVERDOSAGE )

In patients with impaired mechanisms for excreting potassium, the administration of potassium salts can produce hyperkalemia and cardiac arrest. This occurs most commonly in patients given potassium by the intravenous route but may also occur in patients given potassium orally. Potentially fatal hyperkalemia can develop rapidly and be asymptomatic. The use of potassium salts in patients with chronic renal disease, or any other condition which impairs potassium excretion, requires particularly careful monitoring of the serum potassium concentration and appropriate dosage adjustment.

Interaction with Potassium-Sparing Diuretics

Hypokalemia should not be treated by the concomitant administration of potassium salts and a potassium-sparing diuretic (eg, spironolactone, triamterene, or amiloride) since the simultaneous administration of these agents can produce severe hyperkalemia.

Interaction with Angiotensin-Converting Enzyme Inhibitors

Angiotensin-converting enzyme (ACE) inhibitors (eg, captopril, enalapril) will produce some potassium retention by inhibiting aldosterone production. Potassium supplements should be given to patients receiving ACE inhibitors only with close monitoring.

Gastrointestinal Lesions

Solid oral dosage forms of K-Med (Potassium Chloride) can produce ulcerative and/or stenotic lesions of the gastrointestinal tract. Based on spontaneous adverse reaction reports, enteric-coated preparations of K-Med (Potassium Chloride) are associated with an increased frequency of small bowel lesions (40-50 per 100,000 patient years) compared to sustained release wax matrix formulations (less than one per 100,000 patient years). Because of the lack of extensive marketing experience with microencapsulated products, a comparison between such products and wax matrix or enteric-coated products is not available. K-Med (Potassium Chloride) Extended Release Tablets USP, 20 mEq is a tablet formulated to provide a controlled rate of release of microencapsulated K-Med (Potassium Chloride) and thus to minimize the possibility of a high local concentration of potassium near the gastrointestinal wall.

Prospective trials have been conducted in normal human volunteers in which the upper gastrointestinal tract was evaluated by endoscopic inspection before and after 1 week of solid oral K-Med (Potassium Chloride) therapy. The ability of this model to predict events occurring in usual clinical practice is unknown. Trials which approximated usual clinical practice did not reveal any clear differences between the wax matrix and microencapsulated dosage forms. In contrast, there was a higher incidence of gastric and duodenal lesions in subjects receiving a high dose of a wax matrix controlled-release formulation under conditions which did not resemble usual or recommended clinical practice (ie, 96 mEq per day in divided doses of K-Med (Potassium Chloride) administered to fasted patients, in the presence of an anticholinergic drug to delay gastric emptying). The upper gastrointestinal lesions observed by endoscopy were asymptomatic and were not accompanied by evidence of bleeding (Hemoccult testing). The relevance of these findings to the usual conditions (ie, non-fasting, no anticholinergic agent, smaller doses) under which controlled-release K-Med (Potassium Chloride) products are used is uncertain; epidemiologic studies have not identified an elevated risk, compared to microencapsulated products, for upper gastrointestinal lesions in patients receiving wax matrix formulations. K-Med (Potassium Chloride) Extended Release Tablets USP, 20 mEq should be discontinued immediately and the possibility of ulceration, obstruction, or perforation should be considered if severe vomiting, abdominal pain, distention, or gastrointestinal bleeding occurs.

Metabolic Acidosis

Hypokalemia in patients with metabolic acidosis should be treated with an alkalinizing potassium salt such as potassium bicarbonate, potassium citrate, potassium acetate, or potassium gluconate.

PRECAUTIONS

General

The diagnosis of potassium depletion is ordinarily made by demonstrating hypokalemia in a patient with a clinical history suggesting some cause for potassium depletion. In interpreting the serum potassium level, the physician should bear in mind that acute alkalosis per se can produce hypokalemia in the absence of a deficit in total body potassium while acute acidosis per se can increase the serum potassium concentration into the normal range even in the presence of a reduced total body potassium. The treatment of potassium depletion, particularly in the presence of cardiac disease, renal disease, or acidosis requires careful attention to acid-base balance and appropriate monitoring of serum electrolytes, the electrocardiogram, and the clinical status of the patient.

Information for Patients

Physicians should consider reminding the patient of the following: To take each dose with meals and with a full glass of water or other liquid. To take each dose without crushing, chewing, or sucking the tablets. If those patients are having difficulty swallowing whole tablets, they may try one of the following alternate methods of administration:

• Break the tablet in half, and take each half separately with a glass of water.
• Prepare an aqueous suspension as follows:
  

  1. Place the whole tablet(s) in approximately 1/2 glass of water (4 fluid ounces).
  

  2. Allow approximately 2 minutes for the tablet(s) to disintegrate.
  

  3. Stir for about half a minute after the tablet(s) has disintegrated.
  

  4. Swirl the suspension and consume the entire contents of the glass immediately by drinking or by the use of a straw.
  

  5. Add another 1 fluid ounce of water, swirl, and consume immediately.
  

  6. Then, add an additional 1 fluid ounce of water, swirl, and consume immediately.

Aqueous suspension of K-Med (Potassium Chloride) that is not taken immediately should be discarded. The use of other liquids for suspending K-Med (Potassium Chloride) Extended Release Tablets USP, 20 mEq is not recommended.

To take this medicine following the frequency and amount prescribed by the physician. This is especially important if the patient is also taking diuretics and/or digitalis preparations.

To check with the physician at once if tarry stools or other evidence of gastrointestinal bleeding is noticed.

Laboratory Tests

When blood is drawn for analysis of plasma potassium it is important to recognize that artifactual elevations can occur after improper venipuncture technique or as a result of in vitro hemolysis of the sample.

Drug Interactions

Potassium-sparing diuretics, angiotensin-converting enzyme inhibitors.

Carcinogenesis, Mutagenesis, Impairment of Fertility

Carcinogenicity, mutagenicity, and fertility studies in animals have not been performed. Potassium is a normal dietary constituent.

Pregnancy Category C

Animal reproduction studies have not been conducted with K-Med Extended Release Tablets USP, 20 mEq. It is unlikely that potassium supplementation that does not lead to hyperkalemia would have an adverse effect on the fetus or would affect reproductive capacity.

Nursing Mothers

The normal potassium ion content of human milk is about 13 mEq per liter. Since oral potassium becomes part of the body potassium pool, so long as body potassium is not excessive, the contribution of K-Med (Potassium Chloride) supplementation should have little or no effect on the level in human milk.

Pediatric Use

Safety and effectiveness in pediatric patients have not been established.

Geriatric Use

Clinical studies of K-Med (Potassium Chloride) did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the 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.

This drug 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.

ADVERSE REACTIONS

One of the most severe adverse effects is hyperkalemia (see CONTRAINDICATIONS , WARNINGS , and OVERDOSAGE ). There have also been reports of upper and lower gastrointestinal conditions including obstruction, bleeding, ulceration, and perforation (see CONTRAINDICATIONS and WARNINGS ). The most common adverse reactions to oral potassium salts are nausea, vomiting, flatulence, abdominal pain/discomfort, and diarrhea. These symptoms are due to irritation of the gastrointestinal tract and are best managed by diluting the preparation further, taking the dose with meals or reducing the amount taken at one time.

OVERDOSAGE

The administration of oral potassium salts to persons with normal excretory mechanisms for potassium rarely causes serious hyperkalemia. However, if excretory mechanisms are impaired or if potassium is administered too rapidly intravenously, potentially fatal hyperkalemia can result (see CONTRAINDICATIONS and WARNINGS ). It is important to recognize that hyperkalemia is usually asymptomatic and may be manifested only by an increased serum potassium concentration (6.5-8.0 mEq/L) and characteristic electrocardiographic changes (peaking of T-waves, loss of P-waves, depression of S-T segment, and prolongation of the QT-interval). Late manifestations include muscle paralysis and cardiovascular collapse from cardiac arrest (9-12 mEq/L).

Treatment measures for hyperkalemia include the following:

• Patients should be closely monitored for arrhythmias and electrolyte changes.
• Elimination of foods and medications containing potassium and of any agents with potassium-sparing properties such as potassium-sparing diuretics, ARBS, ACE inhibitors, NSAIDS, certain nutritional supplements and many others.
• Intravenous calcium gluconate if the patient is at no risk of developing digitalis toxicity.
• Intravenous administration of 300 to 500 mL/hr of 10% dextrose solution containing 10-20 units of crystalline insulin per 1,000 mL.
• Correction of acidosis, if present, with intravenous sodium bicarbonate.
• Use of exchange resins, hemodialysis, or peritoneal dialysis.

In treating hyperkalemia, it should be recalled that in patients who have been stabilized on digitalis, too rapid a lowering of the serum potassium concentration can produce digitalis toxicity.

The extended release feature means that absorption and toxic effects may be delayed for hours.

Consider standard measures to remove any unabsorbed drug.

DOSAGE AND ADMINISTRATION

The usual dietary intake of potassium by the average adult is 50 to 100 mEq per day. Potassium depletion sufficient to cause hypokalemia usually requires the loss of 200 or more mEq of potassium from the total body store.

Dosage must be adjusted to the individual needs of each patient. The dose for the prevention of hypokalemia is typically in the range of 20 mEq per day. Doses of 40-100 mEq per day or more are used for the treatment of potassium depletion. Dosage should be divided if more than 20 mEq per day is given such that no more than 20 mEq is given in a single dose.

Each K-Med (Potassium Chloride) Extended Release Tablet USP, 20 mEq provides 20 mEq of K-Med (Potassium Chloride).

K-Med (Potassium Chloride) Extended Release Tablets USP, 20 mEq should be taken with meals and with a glass of water or other liquid. This product should not be taken on an empty stomach because of its potential for gastric irritation (see WARNINGS ).

Patients having difficulty swallowing whole tablets may try one of the following alternate methods of administration:

• Break the tablet in half, and take each half separately with a glass of water.
• Prepare an aqueous (water) suspension as follows:
  • Place the whole tablet(s) in approximately 1/2 glass of water (4 fluid ounces).
  • Allow approximately 2 minutes for the tablet(s) to disintegrate.
  • Stir for about half a minute after the tablet(s) has disintegrated.
  • Swirl the suspension and consume the entire contents of the glass immediately by drinking or by the use of a straw.
  • Add another 1 fluid ounce of water, swirl, and consume immediately.
  • Then, add an additional 1 fluid ounce of water, swirl, and consume immediately.

Aqueous suspension of K-Med (Potassium Chloride) that is not taken immediately should be discarded. The use of other liquids for suspending K-Med (Potassium Chloride) Extended Release Tablets USP, 20 mEq is not recommended.

HOW SUPPLIED

K-Med (Potassium Chloride) Extended Release Tablets USP, 20 mEq are available in bottles of 100 (NDC 62037-999-01), bottles of 500 (NDC 62037-999-05), and bottles of 1000 (NDC 62037-999-10). Potassium Chloride Extended Release Tablets USP, 20 mEq are capsule shaped, white to off-white tablets, with “ABRS-123” imprinted on one side and scored on the other side for flexibility of dosing.

Storage Conditions

Keep tightly closed. Store at controlled room temperature, 20°-25°C (68°-77°F).

Manufactured by:

Eurand, Inc.

Vandalia, OH 45377 USA

Distributed by:

Watson Pharma, Inc.

Rev. Date (01/09) 173714

K-Med (Potassium Chloride) 20 Meq