II. Indications
- High Altitude Sickness treatment and prevention
- Pseudotumor Cerebri
-
Glaucoma
- Intraocular Carbonic Anhydrase Inhibitor
- Systemic Acetazolamide (IV or oral) Indications
- Acute angle closure Glaucoma before surgery
- Acute exacerbation of chronic Open Angle Glaucoma
- Other indications
- Periodic Paralysis
- Marfan Syndrome related dural ectasia
- Stable Hypercapnic Respiratory Failure (respiratory stimulant)
- Epilepsy
- FDA approved for Seizures since 1956
- Has been used for Catamenial Epilepsy, Myoclonic, Absence and Generalized Seizures
- Reiss (1996) Ann Pharmacother 30(5):514-9 [PubMed]
III. Contraindications
- Sulfonamide Allergy or Anaphylaxis
- Stevens-Johnson Syndrome or Toxic Epidermal Necrolysis history
- Hyponatremia
- Hypokalemia
- Hyperchloremic Metabolic Acidosis
- Adrenal Insufficiency
- Cirrhosis or other severe liver disease
- Severe renal disease
IV. Mechanism
- Diuretic in the Carbonic Anhydrase Inhibitor Class
- Decreases secretion of Aqueous Humor (Glaucoma)
- Decreases Hydrogen Ion at renal proximal tubule
- Prevents renal bicarbonate reuptake resulting in urine alkalization (and blood acidification)
- Increased renal excretion of Sodium, Potassium, bicarbonate and water
- Results in hypokalemic Metabolic Acidosis and Respiratory Alkalosis (mechanism in High Altitude Illness)
- Lower resting PaCO2
- Higher resting Minute Ventilation
- Increased PaO2
V. Dosing
-
High Altitude Sickness
- Prevention
- Adults: 125 mg orally every 12 hours (FDA approved)
- Up to 250 mg twice daily may be used (but 125 mg is typically sufficient)
- Doses of 1000 mg/day (with added Dexamethasone) have been used for rapid ascent (e.g. rescue)
- Children: 2.5 mg/kg up to 125 mg every 12 hours (off-label)
- Start 24 hours before ascent
- Continue for 72 hours or until acclimitization to highest sleeping altitude
- Adults: 125 mg orally every 12 hours (FDA approved)
- Insomnia at altitude: 125 mg orally at bedtime
- Treatment: Adults
- Start: 250 mg orally twice daily
- Range: 500 to 1000 mg/day divided every 8 to 12 hours (every 12 to 24 hours if extended release)
- Often used in combination with Dexamethasone
- Prevention
-
Pseudotumor Cerebri
- Dose range: 125-250 mg orally daily to three times daily
-
Open Angle Glaucoma acute exacerbation or Acute Narrow Angle Glaucoma prior to surgery
- Dose: 250 mg orally or IV every 4-6 hours (maximum 1 gram/day)
VI. Adverse Effects: Common
- Hypokalemia
- Hyponatremia
- Metabolic Acidosis
- Peripheral Paresthesias (common)
- Polyuria
- Taste Dysfunction (Dysgeusia) with bitter or Metallic Taste
- Headache
- Nausea or Vomiting
- Abdominal Cramping
- Black Stool
- Diarrhea
- Fatigue
- Drowsiness
- Depressed Mood
- Decreased Libido
- Ureteral Stones
VII. Adverse Effects: Uncommon Serious
- Stevens-Johnson Syndrome
- Anaphylaxis
- Blood Dyscrasias
VIII. Drug Interactions
IX. Safety
- Pregnancy Category C
- Safe in Lactation
X. Resources
- Acetazolamide Tablets (DailyMed)
XI. References
- Olson (2020) Clinical Pharmacology, Medmaster, Miami, p. 62-3
- Hamilton (2010) Tarason Pocket Pharmacopeia, p. 224
- Lovecchio (2017) Crit Dec Emerg Med 31(8): 28
- Lovecchio (2022) Crit Dec Emerg Med 36(3): 28
Images: Related links to external sites (from Bing)
Related Studies
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| ACETAZOLAMIDE 125 MG TABLET | Generic | $0.14 each |
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