20 . May , 2019 - Monday
Check todays hot topics or new products

Find a Drug: Advanced

Please Sign in or Register

All about: Methazolamide

Big Image Pronouncation: (meth-ah-ZOLE-ah-mide)
Class: Carbonic anhydrase inhibitor

Trade Names:
- Tablets 25 mg
- Tablets 50 mg

Mechanism of Action


Inhibits carbonic anhydrase enzyme, reducing rate of aqueous humor secretion and, thus, lowering IOP.



Well absorbed from the GI tract, reaching peak plasma levels in 1 to 2 h. The C max for the 25, 50, and 100 mg twice daily dosing regiments are 2.5, 5.1, and 10.7 mcg/mL, respectively. The AUCs are 1,130, 2,571, and 5,418 mcg•min/mL, respectively.


Methazolamide is distributed throughout the body including plasma, cerebrospinal fluid, aqueous humor, RBC, bile, and extracellular fluid. The Vd ranges from 17 to 23 L. Approximately 55% is bound to plasma proteins.


Mean steady-state plasma elimination t ½ is about 14 h. Approximately 25% is recovered unchanged in the urine over the dosing interval and renal Cl accounts for 20% to 25% of the total Cl.


Decrease in IOP usually occurs in 2 to 4 h.


About 6 to 8 h.


About 10 to 18 h.

Indications and Usage

Treatment of ocular conditions where lowering IOP is likely to be of therapeutic benefit (eg, chronic open-angle glaucoma, secondary glaucoma, preoperatively in acute angle-closure glaucoma).


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 (may precipitate hepatic encephalopathy); long-term administration in patients with angle-closure glaucoma.

Dosage and Administration


PO 50 to 100 mg twice daily or 3 times daily.

Drug Interactions

Aspirin (high-dose)

Anorexia, tachypnea, lethargy, coma, and death have been reported.


Use with caution because of risk of developing hypokalemia.

Laboratory Test Interactions

None well documented.

Adverse Reactions


Paresthesias; malaise; drowsiness; confusion; loss of appetite; convulsions.


Urticaria; Stevens-Johnson syndrome; toxic epidermal necrolysis.


Hearing dysfunction; tinnitus; transient myopia.


Electrolyte imbalance.


Taste alteration; GI disturbance (including nausea, vomiting, diarrhea); melena.


Polyuria; hematuria; glucosuria; crystalluria; renal calculi.


Agranulocytosis; aplastic anemia; other blood dyscrasias.


Hepatic insufficiency; fulminant hepatic necrosis.


Metabolic acidosis.


Flaccid paralysis.





Category C .




Safety and efficacy not established.


Patients with known sulfonamide sensitivity may show allergic reactions to methazolamide.

Hepatic Function

Use could precipitate hepatic coma.

Pulmonary conditions

Use in pulmonary obstruction and emphysema may aggravate or precipitate acidosis.

Recent Drug Updates at DrugIndexOnline:

Avonex Prefilled Syringes Avonex Prefilled Syringes
Generic Name: Interferon Beta-1a Intramuscular Injection (Prefilled Syringes) (in-ter-FEER-on BAY-tah) Brand Name: AvonexAvonex Prefilled Syringes is used for:Treating relapsing forms of multiple sclerosis (MS) to reduce the number of flare-ups and slow down the development of physical disabilit more...

Exelon patch Exelon patch
Generic Name: rivastigmine Dosage Form: Patch 1 INDICATIONS AND USAGE 1.1 Alzheimer’s Disease Exelon Patch (rivastigmine transdermal system) is indicated for the treatment of mild to moderate dementia of the Alzheimer’s type. 1.2 Parkinson’s Disease Dementia Exe more...

Glimepiride Glimepiride
Generic Name: Glimepiride (glye-MEP-i-ride) Brand Name: AmarylGlimepiride is used for:Treating type 2 diabetes in patients who cannot control blood sugar levels by diet and exercise alone. It is used along with diet and exercise. It may be used alone or with other antidiabetic medicines. Glimep more...

Goniosol Ophthalmic Goniosol Ophthalmic
Some commonly used brand names are: In the U.S.— Artificial Tears Bion Tears Gonak Goniosoft Goniosol Isopto Alkaline Isopto Plain Isopto Tears Just Tears Lacril Moisture Drops Nature's Tears Ocucoat Ocucoat PF Tearisol Tears Naturale Tears Naturale II Tears Naturale Free Tears Renewed Ul more...

K-Lyte CI K-Lyte CI
Generic Name: potassium bicarbonate and potassium chloride (poe tass EE um) Brand Names: K-Lyte CI, Klorvess Effervescent What is K-Lyte CI (potassium bicarbonate and potassium chloride)? Potassium is a mineral that is found naturally in foods and is necessary for many normal functions more...

Pantoprazole Sodium Pantoprazole Sodium
Pronouncation: (pahn-TOE-prazz-ole SO-dee-uhm) Class: Proton Pump Inhibitor Trade Names: Protonix - Tablets, delayed-release 40 mg - Tablets, delayed-release 20 mg Trade Names: Protonix IV - Powder for Injection 40 mg/vial Panto IV (Canada) Pantoloc (Canada) Mechanism of Action Pharmacology Suppres more...

Procyclidine Procyclidine
Pronouncation: (pro-SIGH-klih-deen) Class: Anticholinergic Trade Names: Kemadrin - Tablets 5 mg Procyclid (Canada) Mechanism of Action Pharmacology Has atropine-like action and exerts antispasmodic effect on smooth muscle. Is potent mydriatic and inhibits salivation; normally has no sympathetic gan more...

Prometrium Prometrium
Generic Name: Progesterone Capsules (pro-JESS-ter-ohn) Brand Name: PrometriumPrometrium should not be used in combination with estrogen to prevent heart disease. Prometrium taken in combination with estrogen can increase the risk of heart disease (including heart attacks), stroke, serious bloo more...