Ballicules › Drugs › Methazolamide
Pronunciation: meth-a-ZOL-a-mide
Mechanism of action: Methazolamide ballicule
Visual mnemonic: Methazolamide mascot“Neptune Zane’s Meat hazard” carbonated soda → carbonic anhydrase inhibitor
What it is Carbonic anhydrase inhibitor; glaucoma.
Why this one It has less renal effect and is often better tolerated than acetazolamide at equivalent pressure reduction.
What limits it Paresthesia, fatigue and metabolic acidosis persist; it is a sulfonamide.
Molecular structure: Methazolamide
FDA-approved for
FDA label
Read the full label on DailyMed ↗
FDA dosing Population Start Target Max
Glaucoma (elevated intraocular pressure) adult 50 mg BID-TID 50-100 mg BID-TID 100 mg TID
Renal Contraindicated in marked kidney disease or dysfunction
Hepatic Contraindicated in marked liver disease/dysfunction; may precipitate hepatic encephalopathy in cirrhosis
Instructions May be used concomitantly with miotic and osmotic agents
Available strengths
Contraindications Depressed serum sodium and/or potassium Marked kidney or liver disease or dysfunction Adrenal gland failure Hyperchloremic acidosis Long-term use in angle-closure glaucoma (organic angle closure may occur)
Cautions Sulfonamide-type reactions incl. Stevens-Johnson syndrome, TEN, fulminant hepatic necrosis, agranulocytosis, aplastic anemia, other blood dyscrasias (rarely fatal) Metabolic acidosis and electrolyte imbalance Transient myopia
Adverse reactions Paresthesias (tingling in extremities) Hearing dysfunction/tinnitus Fatigue, malaise, anorexia, taste alteration GI disturbance (nausea, vomiting, diarrhea) Polyuria Drowsiness, confusion
Pregnancy Category C; teratogenic (skeletal anomalies) in rats; use only if benefit justifies fetal risk
Lactation Undefined
Cost Methazolamide (NEPTAZANE)
What pharmacies pay · NADAC 9/30/26
Strength #/mo generic $/mo CostPlus 25 mg tab 60 BID $37.65 offered 50 mg tab 60 BID $88.10 offered
Generic entry 1993
Principal risk Paraesthesia and metabolic acidosis
Classes and tags
Clinical profile
Therapeutic safety burden 1 / 4
Overdose danger 1 / 4
Weight-gain liability 0 / 4
Sedation liability 0 / 4
QT / Torsades 0 / 4
Direct muscarinic antagonism 0 / 4
Embryofetal risk 1 / 4
Legacy pregnancy category Unknown / historical label unavailable
Defining liability Generally tolerated at therapeutic doses; clinically important risks are agent-specific and increase with interactions or organ impairment.
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urinary alkalinizer
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