Last reviewed 2026-04-20 · How we verify

Neptazane (METHAZOLAMIDE)

Neptazane (METHAZOLAMIDE) is a small molecule drug that targets carbonic anhydrase 3. It is a methazolamide class medication, originally developed by Lederle and currently owned by the same company. Neptazane is FDA-approved for the treatment of angle-closure glaucoma, open-angle glaucoma, and secondary glaucoma. The medication is off-patent, with multiple generic manufacturers available. As an off-patent medication, key safety considerations should be carefully evaluated.

At a glance

Approved indications

• Angle-closure glaucoma
• Open-angle glaucoma
• Secondary glaucoma

Common side effects

• Metabolic acidosis
• Electrolyte imbalance
• Hepatic insufficiency
• Flaccid paralysis
• Photosensitivity
• Convulsions
• Crystalluria
• Renal calculi
• Stevens-Johnson syndrome
• Toxic epidermal necrolysis
• Fulminant hepatic necrosis
• Agranulocytosis

Drug interactions

• steroid therapy
• high-dose aspirin

Key clinical trials

• Stop Retinal Ganglion Cell Dysfunction Study (PHASE3)
• Acamprosate and Methazolamide for Essential Tremor (PHASE2)
• Effect of Acetazolamide and Methazolamide on Hypoxic Exercise Performance (PHASE4)
• Use of Methazolamide to Lower Intraocular Pressure (PHASE4)
• Three New Ideas to Protect Special Forces From the Stress of High Altitude (PHASE4)
• Comparison of Two Different Sedation Protocols During Transvaginal Oocyte Retrieval
• Improving Tumor Oxygenation in Cervical Cancer (PHASE2)
• Muscle Fatigue and Carbonic Anhydrase Inhibitors (PHASE4)

Primary sources

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