Methazolamide

INDICATIONS AND USAGE Methazolamide Tablets, USP are indicated in the treatment of ocular conditions where lowering intraocular pressure is likely to be of therapeutic benefit, such as chronic open-angle glaucoma, secondary glaucoma, and preoperatively in acute angle-closure glaucoma where lowering the intraocular pressure is desired before surgery.

DOSAGE AND ADMINISTRATION: The effective therapeutic dose administered varies from 50 mg to 100 mg two or three times daily. The drug may be used concomitantly with miotic and osmotic agents.

CONTRAINDICATIONS Methazolamide tablets therapy is contraindicated in situations in which sodium and/or potassium serum levels are depressed, in cases of marked kidney or liver disease or dysfunction, in adrenal gland failure, and in hyperchloremic acidosis. In patients with cirrhosis, use may precipitate the development of hepatic encephalopathy. Long-term administration of methazolamide is contraindicated in patients with angle-closure glaucoma, since organic closure of the angle may occur in spite of lowered intraocular pressure.

ADVERSE REACTIONS Adverse reactions, occurring most often early in therapy, include paresthesias, particularly a “tingling” feeling in the extremities; hearing dysfunction or tinnitus; fatigue; malaise; loss of appetite; taste alteration; gastrointestinal disturbances such as nausea, vomiting, and diarrhea; polyuria; and occasional instances of drowsiness and confusion. Metabolic acidosis and electrolyte imbalance may occur. Transient myopia has been reported. This condition invariably subsides upon diminution or discontinuance of the medication. Other occasional adverse reactions include urticaria, melena, hematuria, glycosuria, hepatic insufficiency, flaccid paralysis, photosensitivity, convulsions, and, rarely, crystalluria and renal calculi. Also see PRECAUTIONS: Information for patients for possible reactions common to sulfonamide derivatives. Fatalities have occurred, although rarely, due to severe reactions to sulfonamides including Stevens-Johnson syndrome, toxic epidermal necrolysis, fulminant hepatic necrosis, agranulocytosis, aplastic anemia, and other blood dyscrasias (see WARNINGS ). To report SUSPECTED ADVERSE REACTIONS, contact Bausch & Lomb Incorporated at 1-800-553-5340 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch.

Drug Interactions: Methazolamide should be used with caution in patients on steroid therapy because of the potential for developing hypokalemia. Caution is advised for patients receiving high-dose aspirin and methazolamide concomitantly, as anorexia, tachypnea, lethargy, coma and death have been reported with concomitant use of high-dose aspirin and carbonic anhydrase inhibitors (see WARNINGS ).

DESCRIPTION Methazolamide, a sulfonamide derivative, is a white or faintly yellow, crystalline powder, soluble in dimethyl formamide, slightly soluble in acetone, very slightly soluble in water and alcohol. The chemical name for methazolamide is: Acetamide, N-[5-(aminosulfonyl)-3-methyl-1,3,4-thiadiazol-2(3H)-ylidene]- and it has the following structural formula: C5H8N4O3S2 236.26 Each tablet, for oral administration, contains 25 mg or 50 mg methazolamide. In addition, each tablet contains the following inactive ingredients: colloidal silicon dioxide, croscarmellose sodium, dibasic calcium phosphate dihydrate, magnesium stearate, microcrystalline cellulose, and isopropyl alcohol. lsopropyl alcohol is removed during manufacturing process Chemical Structure

OVERDOSAGE: No data are available regarding methazolamide overdosage in humans as no cases of acute poisoning with this drug have been reported. Animal data suggest that even a high dose of methazolamide is nontoxic. No specific antidote is known. Treatment should be symptomatic and supportive. Electrolyte imbalance, development of an acidotic state, and central nervous system effects might be expected to occur. Serum electrolyte levels (particularly potassium) and blood pH levels should be monitored. Supportive measures may be required to restore electrolyte and pH balance.

HOW SUPPLIED Methazolamide Tablets USP 25 mg: White to off-white, circular, biconvex, uncoated tablet, debossed with “25” on one side and plain on the other side. Bottles of 90 NDC 24208-022-90 Bottles of 100 NDC 24208-022-10 Bottles of 500 NDC 24208-022-50 Bottles of 1,000 NDC 24208-022-01 Methazolamide Tablets USP 50 mg: White to off-white, circular, biconvex, uncoated tablet, debossed with “50” on one side and score line on the other side. Bottles of 90 � NDC 24208-023-90 Bottles of 100 NDC 24208-023-10 Bottles of 500 NDC 24208-023-50 Bottles of 1,000 NDC 24208-023-01 Store at 20°C to 25°C (68°F to 77°F); excursions permitted to 15°C to 30°C (59°F to 86°F) [see USP Controlled Room Temperature]. Dispense in a tight container as defined in the USP, with a child-resistant closure (as required). Distributed by: Bausch & Lomb Americas Inc. Bridgewater, NJ 08807 USA Manufactured by: Micro Labs Limited Goa-403 722, India © 2022 Bausch & Lomb Incorporated or its affiliates Rev. 03/2022 9774900