15 . August , 2018 - Wednesday
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:

Desenex Powder Topical Desenex Powder Topical
Some commonly used brand names are: In the U.S.— Caldesene Medicated Powder Cruex Antifungal Cream Cruex Antifungal Powder Cruex Antifungal Spray Powder Decylenes Powder Desenex Antifungal Cream Desenex Antifungal Liquid Desenex Antifungal Ointment Desenex Antifungal Penetrating Foam Dese more...

Dimenhydrinate Dimenhydrinate
Generic Name: Dimenhydrinate Injection (dye-men-HYE-dri-nate) Brand Name: Generic only. No brands available.Dimenhydrinate is used for:Preventing and treating nausea, vomiting, and dizziness caused by motion sickness. It may also be used for other conditions as determined by your doctor. Dimenhy more...

Doryx Doryx
Generic name: Doxycycline hyclate Brand names: Vibra-Tabs, Vibramycin, Doryx Why is Doryx prescribed? Doxycycline is a broad-spectrum tetracycline antibiotic used against a wide variety of bacterial infections, including Rocky Mountain spotted fever and other fevers caused by ticks, fleas, and l more...

Fiorinal-C ½ Fiorinal-C ½
Some commonly used brand names are: In the U.S.— Ascomp with Codeine No.3 1 Butalbital Compound with Codeine 1 Butinal with Codeine No.3 1 Fiorinal with Codeine No.3 1 Idenal with Codeine 1 Isollyl with Codeine 1 In Canada— Fiorinal-C 1/4 1 Fiorinal-C 1/2 1 Phenaphen with Codeine more...

Insta-Char Pediatric in an Aqueous Base with Cherry  Flavor Insta-Char Pediatric in an Aqueous Base with Cherry Flavor
Some commonly used brand names are: In the U.S.— Actidose-Aqua 1 Actidose with Sorbitol 2 CharcoAid 2 CharcoAid G 1 CharcoAid 2000 1 Insta-Char in an Aqueous Base 1 Insta-Char in an Aqueous Base with Cherry Flavor 1 Insta-Char Pediatric in an Aqueous Base with Cherry Flavor 1 Insta-Char P more...

Mifeprex Mifeprex
Some commonly used brand names are: In the U.S.— Mifeprex Other commonly used names are RU 486 Category Abortifacient Description Mifepristone (mif-i-PRIS-tone)is used to end a pregnancy that is less than 49 days in duration. It works by stopping the supply of hormones that mainta more...

Ovace Foam Ovace Foam
Generic Name: Sulfacetamide Foam (sul-fa-SEE-ta-mide) Brand Name: OvaceOvace Foam is used for:Treating bacterial infections of the skin, including dandruff. It may also be used for other conditions as determined by your doctor. Ovace Foam is a sulfonamide. It works by restricting the production more...

Priftin Priftin
Generic Name: Rifapentine (RIF-ah-pen-teen) Brand Name: PriftinPriftin is used for:Treating tuberculosis (TB). It is used along with other medicines. Priftin is a rifamycin antibiotic. It works by killing or stopping growth of TB organisms. Do NOT use Priftin if:you are allergic to any ingred more...