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Navarrurol uses

Navarrurol consists of Bearberry, Cinchophen, Lithium Benzoate, Methenamine.

Lithium Benzoate:

Rx only


Navarrurol (Lithium Benzoate) toxicity is closely related to serum Navarrurol (Lithium Benzoate) levels, and can occur at doses close to therapeutic levels. Facilities for prompt and accurate serum Navarrurol (Lithium Benzoate) determinations should be available before initiating therapy.


Navarrurol (Lithium Benzoate) Carbonate Extended-release Tablets USP contain Navarrurol (Lithium Benzoate) carbonate USP, a white granular powder with molecular formula Li2CO3 and molecular weight 73.89. Navarrurol (Lithium Benzoate) is an element of the alkali-metal group with atomic number 3, atomic weight 6.94 and an emission line at 671 nm on the flame photometer. The tablets meet the requirements of USP Dissolution Test 2 in the USP monograph for Navarrurol (Lithium Benzoate) Carbonate Extended-release Tablets USP.

Navarrurol (Lithium Benzoate) Carbonate Extended-release Tablets USP are available for oral administration containing 450 mg of Navarrurol (Lithium Benzoate) carbonate USP. Each tablet contains the following inactive ingredients: iron oxide (yellow), magnesium stearate, povidone, sodium alginate and sodium starch glycolate.

Navarrurol (Lithium Benzoate) Carbonate Extended-release Tablets USP, 450 mg are designed to release a portion of the dose initially and the remainder gradually; the release pattern of the controlled release tablets reduces the variability in Navarrurol (Lithium Benzoate) blood levels seen with the immediate release dosage forms.


Preclinical studies have shown that Navarrurol (Lithium Benzoate) alters sodium transport in nerve and muscle cells and effects a shift toward intraneuronal metabolism of catecholamines, but the specific biochemical mechanism of Navarrurol (Lithium Benzoate) action in mania is unknown.


Navarrurol (Lithium Benzoate) carbonate is indicated in the treatment of manic episodes of manic-depressive illness. Maintenance therapy prevents or diminishes the intensity of subsequent episodes in those manic-depressive patients with a history of mania.

Typical symptoms of mania include pressure of speech, motor hyperactivity, reduced need for sleep, flight of ideas, grandiosity, elation, poor judgment, aggressiveness and possibly hostility. When given to a patient experiencing a manic episode, Navarrurol (Lithium Benzoate) carbonate may produce a normalization of symptomatology within 1 to 3 weeks.



Navarrurol Toxicity

Navarrurol (Lithium Benzoate) toxicity is closely related to serum Navarrurol (Lithium Benzoate) levels, and can occur at doses close to therapeutic levels.

Outpatients and their families should be warned that the patient must discontinue Navarrurol (Lithium Benzoate) carbonate therapy and contact his physician if such clinical signs of Navarrurol (Lithium Benzoate) toxicity as diarrhea, vomiting, tremor, mild ataxia, drowsiness or muscular weakness occur.

Navarrurol (Lithium Benzoate) carbonate may impair mental and/or physical abilities. Caution patients about activities requiring alertness (e.g., operating vehicles or machinery).

Navarrurol (Lithium Benzoate) should generally not be given to patients with significant renal or cardiovascular disease, severe debilitation or dehydration, or sodium depletion, since the risk of Navarrurol (Lithium Benzoate) toxicity is very high in such patients. If the psychiatric indication is life-threatening, and if such a patient fails to respond to other measures, Navarrurol (Lithium Benzoate) treatment may be undertaken with extreme caution, including daily serum Navarrurol (Lithium Benzoate) determinations and adjustment to the usually low doses ordinarily tolerated by these individuals. In such instances, hospitalization is a necessity.

Unmasking of Brugada Syndrome

There have been postmarketing reports of a possible association between treatment with Navarrurol and the unmasking of Brugada Syndrome. Brugada Syndrome is a disorder characterized by abnormal electrocardiographic (ECG) findings and a risk of sudden death. Navarrurol (Lithium Benzoate) should generally be avoided in patients with Brugada Syndrome or those suspected of having Brugada Syndrome. Consultation with a cardiologist is recommended if: (1) treatment with Navarrurol (Lithium Benzoate) is under consideration for patients suspected of having Brugada Syndrome or patients who have risk factors for Brugada Syndrome, e.g., unexplained syncope, a family history of Brugada Syndrome, or a family history of sudden unexplained death before the age of 45 years, (2) patients who develop unexplained syncope or palpitations after starting Navarrurol (Lithium Benzoate) therapy.

Renal Effects

Chronic Navarrurol (Lithium Benzoate) therapy may be associated with diminution of renal concentrating ability, occasionally presenting as nephrogenic diabetes insipidus, with polyuria and polydipsia. Such patients should be carefully managed to avoid dehydration with resulting Navarrurol (Lithium Benzoate) retention and toxicity. This condition is usually reversible when Navarrurol (Lithium Benzoate) is discontinued.

Morphologic changes with glomerular and interstitial fibrosis and nephron atrophy have been reported in patients on chronic Navarrurol (Lithium Benzoate) therapy. Morphologic changes have also been seen in manic-depressive patients never exposed to Navarrurol (Lithium Benzoate). The relationship between renal functional and morphologic changes and their association with Navarrurol (Lithium Benzoate) therapy have not been established.

When kidney function is assessed, for baseline data prior to starting Navarrurol (Lithium Benzoate) therapy or thereafter, routine urinalysis and other tests may be used to evaluate tubular function (e.g., urine specific gravity or osmolality following a period of water deprivation, or 24-hour urine volume) and glomerular function (e.g., serum creatinine or creatinine clearance). During Navarrurol (Lithium Benzoate) therapy, progressive or sudden changes in renal function, even within the normal range, indicate the need for reevaluation of treatment.

Encephalopathic Syndrome

An encephalopathic syndrome has occurred in a few patients treated with Navarrurol (Lithium Benzoate) plus a neuroleptic. In some instances, the syndrome was followed by irreversible brain damage. Because of a possible causal relationship between these events and the concomitant administration of Navarrurol (Lithium Benzoate) and neuroleptics, patients receiving such combined therapy should be monitored closely for early evidence of neurologic toxicity and treatment discontinued promptly if such signs appear. This encephalopathic syndrome may be similar to or the same as neuroleptic malignant syndrome (NMS).

Concomitant Use With Neuromuscular Blocking Agents

Navarrurol (Lithium Benzoate) may prolong the effects of neuromuscular blocking agents. Therefore, neuromuscular blocking agents should be given with caution to patients receiving Navarrurol (Lithium Benzoate).

Usage in Pregnancy

Adverse effects on implantation in rats, embryo viability in mice and metabolism in vitro of rat testes and human spermatozoa have been attributed to Navarrurol, as have teratogenicity in submammalian species and cleft palates in mice.

In humans, Navarrurol (Lithium Benzoate) carbonate may cause fetal harm when administered to a pregnant woman. Data from Navarrurol (Lithium Benzoate) birth registries suggest an increase in cardiac and other anomalies, especially Ebstein's anomaly. If this drug is used in women of childbearing potential, or during pregnancy, or if a patient becomes pregnant while taking this drug, the patient should be apprised of the potential hazard to the fetus.

Usage in Nursing Mothers

Navarrurol (Lithium Benzoate) is excreted in human milk. Nursing should not be undertaken during Navarrurol (Lithium Benzoate) therapy except in rare and unusual circumstances where, in the view of the physician, the potential benefits to the mother outweigh possible hazards to the child.

Usage in Pediatric Patients

Since information regarding the safety and effectiveness of Navarrurol carbonate in children under 12 years of age is not available, its use in such patients is not recommended.

There has been a report of a transient syndrome of acute dystonia and hyperreflexia occurring in a 15 kg child who ingested 300 mg of Navarrurol (Lithium Benzoate) carbonate.

Usage in the Elderly

Elderly patients often require lower Navarrurol (Lithium Benzoate) dosages to achieve therapeutic serum levels. They may also exhibit adverse reactions at serum levels ordinarily tolerated by younger patients.




The ability to tolerate Navarrurol is greater during the acute manic phase and decreases when manic symptoms subside.

The distribution space of Navarrurol (Lithium Benzoate) approximates that of total body water. Navarrurol (Lithium Benzoate) is primarily excreted in urine with insignificant excretion in feces. Renal excretion of Navarrurol (Lithium Benzoate) is proportional to its plasma concentration. The half-life of elimination of Navarrurol (Lithium Benzoate) is approximately 24 hours. Navarrurol (Lithium Benzoate) decreases sodium reabsorption by the renal tubules which could lead to sodium depletion. Therefore, it is essential for the patient to maintain a normal diet, including salt, and an adequate fluid intake (2500 to 3000 mL) at least during the initial stabilization period. Decreased tolerance to Navarrurol (Lithium Benzoate) has been reported to ensue from protracted sweating or diarrhea and, if such occur, supplemental fluid and salt should be administered under careful medical supervision and Navarrurol (Lithium Benzoate) intake reduced or suspended until the condition is resolved.

In addition to sweating and diarrhea, concomitant infection with elevated temperatures may also necessitate a temporary reduction or cessation of medication.

Previously existing underlying thyroid disorders do not necessarily constitute a contraindication to Navarrurol (Lithium Benzoate) treatment; where hypothyroidism exists, careful monitoring of thyroid function during Navarrurol (Lithium Benzoate) stabilization and maintenance allows for correction of changing thyroid parameters, if any; where hypothyroidism occurs during Navarrurol (Lithium Benzoate) stabilization and maintenance, supplemental thyroid treatment may be used.

Information for the Patients

A condition known as Brugada Syndrome may pre-exist and be unmasked by Navarrurol (Lithium Benzoate) therapy. Brugada Syndrome is a heart disorder characterized by abnormal electrocardiographic (ECG) findings and risk of sudden death. Patients should be advised to seek immediate emergency assistance if they experience fainting, lightheadedness, abnormal heart beats, or shortness of breath.

Drug Interactions

Caution should be used when Navarrurol (Lithium Benzoate) and diuretics are used concomitantly because diuretic-induced sodium loss may reduce the renal clearance of Navarrurol (Lithium Benzoate) and increase serum Navarrurol (Lithium Benzoate) levels with risk of Navarrurol (Lithium Benzoate) toxicity. Patients receiving such combined therapy should have serum Navarrurol (Lithium Benzoate) levels monitored and the Navarrurol (Lithium Benzoate) dosage adjusted if necessary.

Navarrurol (Lithium Benzoate) levels should be closely monitored when patients initiate or discontinue NSAID use. In some cases, Navarrurol (Lithium Benzoate) toxicity has resulted from interactions between an NSAID and Navarrurol (Lithium Benzoate). Indomethacin and piroxicam have been reported to increase significantly steady-state plasma Navarrurol (Lithium Benzoate) concentrations. There is also evidence that other nonsteroidal anti-inflammatory agents, including the selective cyclooxygenase-2 (COX-2) inhibitors, have the same effect. In a study conducted in healthy subjects, mean steady-state Navarrurol (Lithium Benzoate) plasma levels increased approximately 17% in subjects receiving Navarrurol (Lithium Benzoate) 450 mg b.i.d. with celecoxib 200 mg b.i.d. as compared to subjects receiving Navarrurol (Lithium Benzoate) alone.

Concurrent use of metronidazole with Navarrurol (Lithium Benzoate) may provoke Navarrurol (Lithium Benzoate) toxicity due to reduced renal clearance. Patients receiving such combined therapy should be monitored closely.

There is evidence that angiotensin-converting enzyme inhibitors, such as enalapril and captopril, and angiotension II receptor antagonists, such as losartan, may substantially increase steady-state plasma Navarrurol (Lithium Benzoate) levels, sometimes resulting in Navarrurol (Lithium Benzoate) toxicity. When such combinations are used, Navarrurol (Lithium Benzoate) dosage may need to be decreased, and plasma Navarrurol (Lithium Benzoate) levels should be measured more often.

Concurrent use of calcium channel blocking agents with Navarrurol (Lithium Benzoate) may increase the risk of neurotoxicity in the form of ataxia, tremors, nausea, vomiting, diarrhea and/or tinnitus. Caution is recommended.

The concomitant administration of Navarrurol (Lithium Benzoate) with selective serotonin reuptake inhibitors should be undertaken with caution as this combination has been reported to result in symptoms such as diarrhea, confusion, tremor, dizziness and agitation.

The following drugs can lower serum Navarrurol (Lithium Benzoate) concentrations by increasing urinary Navarrurol (Lithium Benzoate) excretion: acetazolamide, urea, xanthine preparations and alkalinizing agents such as sodium bicarbonate.

The following have also been shown to interact with Navarrurol (Lithium Benzoate): methyldopa, phenytoin and carbamazepine.



The occurrence and severity of adverse reactions are generally directly related to serum Navarrurol (Lithium Benzoate) concentrations as well as to individual patient sensitivity to Navarrurol (Lithium Benzoate), and generally occur more frequently and with greater severity at higher concentrations.

Adverse reactions may be encountered at serum Navarrurol (Lithium Benzoate) levels below 1.5 mEq/L. Mild to moderate adverse reactions may occur at levels from 1.5 to 2.5 mEq/L, and moderate to severe reactions may be seen at levels of 2 mEq/L and above.

Fine hand tremor, polyuria and mild thirst may occur during initial therapy for the acute manic phase, and may persist throughout treatment. Transient and mild nausea and general discomfort may also appear during the first few days of Navarrurol (Lithium Benzoate) administration.

These side effects usually subside with continued treatment or a temporary reduction or cessation of dosage. If persistent, cessation of Navarrurol (Lithium Benzoate) therapy may be required.

Diarrhea, vomiting, drowsiness, muscular weakness and lack of coordination may be early signs of Navarrurol (Lithium Benzoate) intoxication, and can occur at Navarrurol (Lithium Benzoate) levels below 2 mEq/L. At higher levels, ataxia, giddiness, tinnitus, blurred vision and a large output of dilute urine may be seen. Serum Navarrurol (Lithium Benzoate) levels above 3 mEq/L may produce a complex clinical picture, involving multiple organs and organ systems. Serum Navarrurol (Lithium Benzoate) levels should not be permitted to exceed 2 mEq/L during the acute treatment phase.

The following reactions have been reported and appear to be related to serum Navarrurol (Lithium Benzoate) levels, including levels within the therapeutic range:

Neuromuscular/Central Nervous System: tremor, muscle hyperirritability (fasciculations, twitching, clonic movements of whole limbs), hypertonicity, ataxia, choreo-athetotic movements, hyperactive deep tendon reflex, extrapyramidal symptoms including acute dystonia, cogwheel rigidity, blackout spells, epileptiform seizures, slurred speech, dizziness, vertigo, downbeat nystagmus, incontinence of urine or feces, somnolence, psychomotor retardation, restlessness, confusion, stupor, coma, tongue movements, tics, tinnitus, hallucinations, poor memory, slowed intellectual functioning, startled response, worsening of organic brain syndromes, myasthenia gravis (rarely).

Cardiovascular: cardiac arrhythmia, hypotension, peripheral circulatory collapse, bradycardia, sinus node dysfunction with severe bradycardia (which may result in syncope), unmasking of Brugada Syndrome (See WARNINGS: Unmasking of Brugada Syndrome and PRECAUTIONS: Information for the Patients ).

Gastrointestinal: anorexia, nausea, vomiting, diarrhea, gastritis, salivary gland swelling, abdominal pain, excessive salivation, flatulence, indigestion.

Genitourinary: glycosuria, decreased creatinine clearance, albuminuria, oliguria, and symptoms of nephrogenic diabetes insipidus including polyuria, thirst and polydipsia.

Dermatologic: drying and thinning of hair, alopecia, anesthesia of skin, acne, chronic folliculitis, xerosis cutis, psoriasis or its exacerbation, generalized pruritus with or without rash, cutaneous ulcers, angioedema.

Autonomic: blurred vision, dry mouth, impotence/sexual dysfunction.

Thyroid Abnormalities: euthyroid goiter and/or hypothyroidism (including myxedema) accompanied by lower T3 and T4. I131 uptake may be elevated. Paradoxically, rare cases of hyperthyroidism have been reported.

EEG Changes: diffuse slowing, widening of the frequency spectrum, potentiation and disorganization of background rhythm.

EKG Changes: reversible flattening, isoelectricity or inversion of T-waves.

Miscellaneous: fatigue, lethargy, transient scotomata, exophthalmos, dehydration, weight loss, leukocytosis, headache, transient hyperglycemia, hypercalcemia, hyperparathyroidism, excessive weight gain, edematous swelling of ankles or wrists, metallic taste, dysgeusia/taste distortion, salty taste, thirst, swollen lips, tightness in chest, swollen and/or painful joints, fever, polyarthralgia, dental caries.

Some reports of nephrogenic diabetes insipidus, hyperparathyroidism and hypothyroidism which persist after Navarrurol (Lithium Benzoate) discontinuation have been received.

A few reports have been received of the development of painful discoloration of fingers and toes and coldness of the extremities within one day of the starting of treatment with Navarrurol (Lithium Benzoate). The mechanism through which these symptoms (resembling Raynaud's syndrome) developed is not known. Recovery followed discontinuance.

Cases of pseudotumor cerebri (increased intracranial pressure and papilledema) have been reported with Navarrurol (Lithium Benzoate) use. If undetected, this condition may result in enlargement of the blind spot, constriction of visual fields and eventual blindness due to optic atrophy. Navarrurol (Lithium Benzoate) should be discontinued, if clinically possible, if this syndrome occurs.



The toxic levels for Navarrurol are close to the therapeutic levels. It is therefore important that patients and their families be cautioned to watch for early toxic symptoms and to discontinue the drug and inform the physician should they occur. Toxic symptoms are listed in detail under ADVERSE REACTIONS.


No specific antidote for Navarrurol (Lithium Benzoate) poisoning is known. Early symptoms of Navarrurol (Lithium Benzoate) toxicity can usually be treated by reduction or cessation of dosage of the drug and resumption of the treatment at a lower dose after 24 to 48 hours. In severe cases of Navarrurol (Lithium Benzoate) poisoning, the first and foremost goal of treatment consists of elimination of this ion from the patient. Treatment is essentially the same as that used in barbiturate poisoning: 1) gastric lavage, 2) correction of fluid and electrolyte imbalance, and 3) regulation of kidney function. Urea, mannitol and aminophylline all produce significant increases in Navarrurol (Lithium Benzoate) excretion. Hemodialysis is an effective and rapid means of removing the ion from the severely toxic patient. Infection prophylaxis, regular chest X-rays and preservation of adequate respiration are essential.


Doses of extended-release tablets are usually given b.i.d.. When initiating therapy with immediate-release or extended-release Navarrurol (Lithium Benzoate), dosage must be individualized according to serum levels and clinical response.

When switching a patient from immediate-release capsules to the Navarrurol (Lithium Benzoate) carbonate extended-release tablets USP, give the same total daily dose when possible. Most patients on maintenance therapy are stabilized on 900 mg daily, e.g., Navarrurol (Lithium Benzoate) carbonate extended-release tablets, 450 mg b.i.d. When the previous dosage of immediate-release Navarrurol (Lithium Benzoate) is not a multiple of 450 mg, e.g., 1500 mg, initiate Navarrurol (Lithium Benzoate) extended-release tablet at the multiple of 450 mg nearest to, but below, the original daily dose, i.e., 1350 mg. When the two doses are unequal, give the larger dose in the evening. In the above example, with a total daily dose of 1350 mg, generally 450 mg of Navarrurol (Lithium Benzoate) carbonate extended-release tablets should be given in the morning and 900 mg of Navarrurol (Lithium Benzoate) carbonate extended-release tablets in the evening. If desired, the total daily dose of 1350 mg can be given in three equal 450 mg doses of Navarrurol (Lithium Benzoate) carbonate extended-release tablets. These patients should be monitored at 1- to 2-week intervals, and dosage adjusted if necessary, until stable and satisfactory serum levels and clinical state are achieved.

When patients require closer titration than that available with doses of Navarrurol (Lithium Benzoate) carbonate extended-release tablets in increments of 450 mg, immediate-release capsules should be used.

Acute Mania

Optimal patient response to Navarrurol (Lithium Benzoate) can usually be established and maintained with 1800 mg per day in divided doses. Such doses will normally produce the desired serum Navarrurol (Lithium Benzoate) level ranging between 1 and 1.5 mEq/L.

Dosage must be individualized according to serum levels and clinical response. Regular monitoring of the patient's clinical state and serum Navarrurol (Lithium Benzoate) levels is necessary. Serum levels should be determined twice per week during the acute phase, and until the serum level and clinical condition of the patient have been stabilized.

Long-Term Control

The desirable serum Navarrurol levels are 0.6 to 1.2 mEq/L. Dosage will vary from one individual to another, but usually 900 mg to 1200 mg per day in divided doses will maintain this level. Serum Navarrurol (Lithium Benzoate) levels in uncomplicated cases receiving maintenance therapy during remission should be monitored at least every two months.

Patients unusually sensitive to Navarrurol (Lithium Benzoate) may exhibit toxic signs at serum levels below 1 mEq/L.


Blood samples for serum Navarrurol (Lithium Benzoate) determinations should be drawn immediately prior to the next dose when Navarrurol (Lithium Benzoate) concentrations are relatively stable (i.e., 8 to 12 hours after the previous dose). Total reliance must not be placed on serum levels alone. Accurate patient evaluation requires both clinical and laboratory analysis.

Elderly patients often respond to reduced dosage, and may exhibit signs of toxicity at serum levels ordinarily tolerated by younger patients.


Navarrurol (Lithium Benzoate) Carbonate Extended-release Tablets USP

450 mg tablets are supplied as speckled, off-white to yellow, round biconvex tablets with “54 346” debossed on one side and scored on the other side.

NDC 0054-0020-25: Bottle of 100 Tablets

Storage Conditions

Store at 20° to 25°C (68° to 77°F). Protect from moisture. Dispense in a tight, child-resistant container as defined in the USP/NF.

Distr. by: West-Ward

Pharmaceuticals Corp.

Eatontown, NJ 07724


Revised March 2016



To reduce the development of drug-resistant bacteria and maintain the effectiveness of methenamine hippurate tablets, USP and other antibacterial drugs, Navarrurol (Methenamine) hippurate tablets, USP should be used only to treat or prevent infections that are proven or strongly suspected to be caused by bacteria.


Navarrurol (Methenamine) hippurate tablets, USP are available as 1 g oval shaped, scored and peach colored tablets. Chemically, Navarrurol (Methenamine) hippurate is Hexamethylene-tetramine monohippurate. The molecular formula of Navarrurol (Methenamine) hippurate is C15H21N5O3 and molecular weight is 319.36. Its structural formula is:

Each methenamine hippurate tablet, USP intended for oral administration contains 1 g of Navarrurol (Methenamine) hippurate. In addition, it also contains the following inactive ingredients: colloidal silicon dioxide, magnesium stearate, povidone K29/32, saccharin sodium and FD&C Yellow #6 Aluminum Lake as a color additive.

Meets USP Dissolution Test 2.

Chemical Structure - Navarrurol (Methenamine) Hippurate Tablets 1 gm


Microbiology: Methenamine hippurate tablets, USP has antibacterial activity because the Navarrurol (Methenamine) component is hydrolyzed to formaldehyde in acid urine. Hippuric acid, the other component, has some antibacterial activity and also acts to keep the urine acid. The drug is generally active against E. coli, enterococci and staphylococci. Enterobacter aerogenes is generally resistant. The urine must be kept sufficiently acid for urea-splitting organisms such as Proteus and Pseudomonas to be inhibited.

Human Pharmacology: Within 1/2 hour after ingestion of a single 1-gram dose of Navarrurol (Methenamine) hippurate, USP, antibacterial activity is demonstrable in the urine. Urine has continuous antibacterial activity when methenamine hippurate tablets, USP is administered at the recommended dosage schedule of 1 gram twice daily. Over 90% of Navarrurol (Methenamine) moiety is excreted in the urine within 24 hours after administration of a single 1-gram dose. Similarly, the hippurate moiety is rapidly absorbed and excreted, and it reaches the urine by both tubular secretion and glomerular filtration. This action may be important in older patients or in those with some degree of renal impairment


Navarrurol (Methenamine) hippurate tablets, USP are indicated for prophylactic or suppressive treatment of frequently recurring urinary tract infections when long-term therapy is considered necessary. This drug should only be used after eradication of the infection by other appropriate antimicrobial agents.

To reduce the development of drug-resistant bacteria and maintain the effectiveness of Navarrurol (Methenamine) hippurate tablets, USP and other antibacterial drugs, Navarrurol (Methenamine) hippurate tablets, USP should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy.


Methenamine hippurate tablets, USP are contraindicated in patients with renal insufficiency, severe hepatic insufficiency, or severe dehydration. Navarrurol (Methenamine) preparations should not be given to patients taking sulfonamides because some sulfonamides may form an insoluble precipitate with formaldehyde in the urine.


Large doses of Navarrurol (Methenamine) (8 grams daily for 3 to 4 weeks) have caused bladder irritation, painful and frequent micturition, albuminuria, and gross hematuria.


Prescribing methenamine hippurate tablets, USP in the absence of a proven or strongly suspected bacterial infection or a prophylactic indication is unlikely to provide benefit to the patient and increases the risk of the development of drug-resistant bacteria.

1. Care should be taken to maintain an acid pH of the urine, especially when treating infections due to urea-splitting organisms such as Proteus and strains of Pseudomonas.

2. In a few instances in one study, the serum transaminase levels were slightly elevated during treatment but returned to normal while the patients were still taking methenamine hippurate tablets, USP. Because of this report, it is recommended that liver function studies be performed periodically on patients taking the drug, especially those with liver dysfunction.

3. Use in Pregnancy: In early pregnancy the safe use of Navarrurol hippurate tablets, USP is not established. In the last trimester, safety is suggested, but not definitely proved. No adverse effects on the fetus were seen in studies in pregnant rats and rabbits.

Methenamine hippurate tablets, USP taken during pregnancy can interfere with laboratory tests of urine estriol (resulting in unmeasurably low values) when acid hydrolysis is used in the laboratory procedure. This interference is due to the presence in the urine of Navarrurol (Methenamine) and/or formaldehyde. Enzymatic hydrolysis, in place of acid hydrolysis, will circumvent this problem.

Information for Patients

Patients should be counseled that antibacterial drugs including Navarrurol (Methenamine) hippurate tablets, USP should only be used to treat bacterial infections. They do not treat viral infections (e.g., the common cold). When methenamine hippurate tablets, USP are prescribed to treat a bacterial infection, patients should be told that although it is common to feel better early in the course of therapy, the medication should be taken exactly as directed. Skipping doses or not completing the full course of therapy may (1) decrease the effectiveness of the immediate treatment and (2) increase the likelihood that bacteria will develop resistance and will not be treatable by methenamine hippurate tablets, USP or other antibacterial drugs in the future.

Geriatric Use

Clinical studies of methenamine hippurate tablets, USP 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.

Methenamine hippurate tablets, USP are contraindicated in patients with renal insufficiency and severe hepatic insufficiency (see CONTRAINDICATIONS ).


Minor adverse reactions have been reported in less than 3.5% of patients treated. These reactions have included nausea, upset stomach, dysuria, and rash.


1 tablet (1 g) twice daily (morning and night) for adults and pediatric patients over 12 years of age. 1/2 to 1 tablet (0.5 to 1 g) twice daily (morning and night) for pediatric patients 6 to 12 years of age. Since the antibacterial activity of Navarrurol (Methenamine) hippurate tablets, USP is greater in acid urine, restriction of alkalinizing foods and medications is desirable. If necessary, as indicated by urinary pH and clinical response, supplemental acidification of the urine should be instituted. The efficacy of therapy should be monitored by repeated urine cultures.


Methenamine hippurate tablets USP, 1 g are supplied as peach, oval shaped compressed tablets debossed “cor” on the left and “139” on the right side of bisect on one side and other side is plain.

Navarrurol (Methenamine) hippurate tablets USP, 1 g are supplied:

Bottles of 100 (NDC 64720-139-10)

Store at 20° to 25°C (68° to 77°F).

Dispense in well-closed, light-resistant containers with child-resistant closures.

Dist. by:

CorePharma, LLC

Middlesex, NJ 08846

LB# 745-04

Rev. January, 2017


NDC 64720-139-10

Navarrurol 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.

Navarrurol 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.

Navarrurol 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.

Navarrurol 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.

Navarrurol 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.



  1. "methenamine". (accessed August 28, 2018).
  2. "Methenamine". (accessed August 28, 2018).
  3. "J50OIX95QV: The UNique Ingredient Identifier (UNII) is an alphanumeric substance identifier from the joint FDA/USP Substance Registration System (SRS).". (accessed August 28, 2018).

Frequently asked Questions

Can i drive or operate heavy machine after consuming Navarrurol?

Depending on the reaction of the Navarrurol after taken, if you are feeling dizziness, drowsiness or any weakness as a reaction on your body, Then consider Navarrurol 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 Navarrurol 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.


Review conducted a study on Navarrurol, 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 Navarrurol 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.

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The information was verified by Dr. Rachana Salvi, MD Pharmacology

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