Side Effects of Acetazolamide

Common and Dose-Dependent Side Effects

The Journal of Neurology, Neurosurgery and Psychiatry recommends starting at lower doses (250-500mg twice daily) and gradually titrating upward to improve tolerability, with only 44% of participants able to tolerate the maximum dose of 4g daily in clinical trials 1
The American Academy of Ophthalmology notes that hematologic effects, including blood dyscrasias such as aplastic anemia and thrombocytopenia, can occur in rare cases, and renal effects, including increased risk of kidney stones, can also occur 2
Central nervous system effects, including confusion, depression, and cognitive slowing, can occur, particularly at higher doses 1

The American College of Obstetricians and Gynecologists classifies acetazolamide as FDA Pregnancy Category C, indicating potential risks to the fetus based on animal studies 2
Patients with sulfonamide allergy should not use acetazolamide, according to the American Academy of Allergy, Asthma, and Immunology 2
The National Kidney Foundation recommends using acetazolamide with extreme caution in patients with impaired renal function, as it can accumulate and lead to toxicity 2

The American Liver Foundation notes that severe liver disease is a contraindication for acetazolamide use 3
The American Academy of Ophthalmology states that adrenal gland failure and hyperchloremic acidosis are also contraindications for acetazolamide use 2

The European Respiratory Society guidelines list vertigo, a form of dizziness, as one of the adverse events associated with carbonic anhydrase inhibitors, including acetazolamide, representing class-specific toxicity that clinicians should anticipate when prescribing these medications 4