AcetaZOLAMIDE
(ah set a zole’ ah mide)
Apo-Acetazolamide (CAN), Diamox Sequels
PREGNANCY CATEGORY C
Drug Classes
Antiepileptic
Antiglaucoma drug
Carbonic anhydrase inhibitor
Diuretic
Sulfonamide (nonbacteriostatic)
Therapeutic Actions
Inhibits the enzyme carbonic anhydrase. This action decreases aqueous humor formation in the eye, IOP, and hydrogen ion secretion by renal tubule cells, and increases sodium, potassium, bicarbonate, and water excretion by the kidney, causing a diuretic effect. In epilepsy, carbonic anhydrase inhibition seems to retard abnormal, excessive discharge from CNS neurons.
Indications
Adjunctive treatment of chronic open-angle glaucoma, secondary glaucoma
Preoperative use in acute angle-closure glaucoma when delay of surgery is desired to lower IOP
Edema caused by heart failure, drug-induced edema
Centrencephalic epilepsy (absence, unlocalized seizures)
Prophylaxis and treatment of acute mountain sickness
Unlabeled uses: Malignant glaucoma, migraine prevention, familial periodic paralysis, cystine or uric acid renal calculi prevention, tardive dyskinesia
Contraindications and Cautions
Contraindicated with allergy to acetazolamide, antibacterial sulfonamides, or thiazides; chronic noncongestive angle-closure glaucoma; cirrhosis.
Use cautiously with fluid or electrolyte imbalance (specifically decreased Na+, decreased K+, hyperchloremic acidosis), renal disease, hepatic disease (risk of hepatic coma if acetazolamide is given), adrenocortical insufficiency, respiratory acidosis, COPD, lactation.
Available Forms
Tablets—125, 250 mg; ER capsules—500 mg; powder for injection—500 mg/vial
Dosages
Adults
Open-angle glaucoma: 250 mg–1 g/day PO, usually in divided doses or ER capsules–1 capsule bid (morning and evening). Do not exceed 1 g/day.
Acute congestive angle-closure glaucoma: 500 mg PO bid (ER capsules) or 250 mg PO q4h; may use a leading dose of 500 mg followed by 125–250 mg every 4 hr.
Secondary glaucoma and preoperatively: 250 mg every 4 hr or 250 mg bid PO or 500 mg PO bid (ER capsules), or 500 mg followed by 125–250 mg every 4 hr. May be given IV for rapid relief of increased IOP—500 mg IV, then 125–250 mg PO every 4 hr.
Diuresis in heart failure: 250–375 mg (5 mg/kg) daily in the morning. Most effective if given on alternate days or for 2 days alternating with a day of rest.
Drug-induced edema: 250–375 mg once every day or for 1 or 2 days alternating with a day of rest.
Epilepsy: 8–30 mg/kg/day in divided doses. When given in combination with other antiepileptics, starting dose is 250 mg daily. SR preparation is not recommended for this use. Range of dosing: 375–1,000 mg/day.Stay updated, free articles. Join our Telegram channel
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