Prescription medicine
Acetazolamide First approved as Diamox
Acetazolamide (Diamox) is a prescription medicine with an FDA approval on record since 1953. FDA's NDC Directory lists it from 38 generic labelers, and pharmacies paid $0.134 per acetazolamide 250 mg tablet in the October 7, 2026 NADAC survey.
- Generic listed
Check it at the source: the acetazolamide FDA label on DailyMed (effective August 19, 2026, Strides Pharma Science Limited); the NDA 8943 record on Drugs@FDA; every acetazolamide label on DailyMed.
Highlights of the record
FDA label of August 19, 2026; NDC Directory, Drugs@FDA and Orange Book, October 8, 2026; NADAC October 7, 2026
Used for
From the label: indications and usageFor adjunctive treatment of: edema due to congestive heart failure;
Forms and strengths
- 125 mg
- 250 mg
- 500 mg
- 500 mg/5ml
Tablet; extended-release capsule; injection (powder) (lyophilized) for solution; capsule; injection (powder) for solution.
On the market
- Earliest approval on file
- July 27, 1953 Diamox, Teva Branded Pharm; Drugs@FDA’s file, where older or withdrawn approvals can be missing
- Generic approvals
- 37 first July 18, 1974; 27 with a marketed status in Drugs@FDA
- Labelers listed (NDC)
- 38 of which 38 under generic applications, 0 under brand applications, repackagers included
Supply and safety
- Pharmacy cost (NADAC)
- $0.134 per tablet Acetazolamide 250 mg tablet
- Shortage (FDA)
- No current entry
- Recalls by its makers (FDA)
- 2 since 2012 0 Class I among all firms' recalls; latest August 24, 2024; 1 more by firms not listed as its makers
- FAERS reports
- 6,032 through July 30, 2026
What is acetazolamide used for?
From the label: indications and usageFor adjunctive treatment of: edema due to congestive heart failure; drug-induced edema; centrencephalic epilepsies (petit mal, unlocalized seizures); chronic simple (open-angle) glaucoma, secondary glaucoma, and preoperatively in acute angle-closure glaucoma where delay of surgery is desired in order to lower intraocular pressure. Acetazolamide Tablets are also indicated for the prevention or amelioration of symptoms associated with acute mountain sickness in climbers attempting rapid ascent and in those who are very susceptible to acute mountain sickness despite gradual ascent.
FDA pharmacologic class: Carbonic Anhydrase Inhibitor.
Source: FDA drug label (Acetazolamide), Strides Pharma Science Limited, effective August 19, 2026 (SPL set 4813b9dd-5f58-44bb-ad64-cdb331828080), via openFDA; the full label on DailyMed
Is there a generic for acetazolamide (Diamox)?
The FDA approved the first generic acetazolamide on July 18, 1974. 37 generic applications are approved; 27 of them carry a current (not discontinued) marketing status in Drugs@FDA; that status is not evidence that the generic is on sale.
FDA's NDC Directory lists acetazolamide from 38 labelers under a generic (ANDA) application. A listing means the company has registered the product for sale; it does not show that every pharmacy stocks it.
- 1953 earliest approval on file
- 1974 first generic approved
- red ticks recalls
Source: Drugs@FDA, FDA NDC Directory and the Orange Book (openFDA bulk files, October 8, 2026)
What do pharmacies pay for acetazolamide (Diamox)?
In CMS's NADAC survey of October 7, 2026, pharmacies paid $0.134 per Acetazolamide 250 mg tablet, down 10% from $0.149 on October 8, 2025. The chart's scale runs from the lowest to the highest price shown, not from zero. NADAC is what retail pharmacies paid their wholesalers, per unit, in CMS's monthly survey; what a patient pays depends on insurance and the pharmacy.
- Acetazolamide 250 mg tablet (generic)
| Strength and form | Brand or generic | Pharmacy cost | 30 tablets, or one pen or vial | 12-month change |
|---|---|---|---|---|
| Acetazolamide 125 mg tablet | Generic | $0.0965 per tablet | $2.89 | -24% |
| Acetazolamide 250 mg tablet | Generic | $0.134 per tablet | $4.02 | -10% |
| Acetazolamide ER 500 mg capsule | Generic | $0.288 per capsule | $8.65 | +5% |
Source: CMS National Average Drug Acquisition Cost (NADAC) survey, October 7, 2026: what retail pharmacies paid per unit; not a counter price
Has acetazolamide been recalled?
The FDA's Enforcement Report lists 3 recalls naming acetazolamide since 2012: 0 Class I (the most serious), 2 Class II, 1 Class III; 1 still ongoing. 1 of them is by a firm that FDA's NDC Directory does not list as a maker of acetazolamide and that holds no application for it in Drugs@FDA, such as compounding pharmacies or bulk-ingredient suppliers; the recall notice names the product recalled. A recall names products and lots, not every product of the medicine.
| Started | Class | Company | Reason |
|---|---|---|---|
| August 24, 2024 | Class III | Rubicon Research Private Limited | Discoloration |
| March 15, 2021 | Class II | Cardinal Health Inc. | CGMP Deviations: Intermittent exposure to temperature excursion during storage. |
| May 25, 2012 | Class II | Franck's Lab Inc., d.b.a. Franck's Compounding Lab not a listed maker | Lack of Assurance of Sterility: Franck's Lab Inc. initiated a recall of all Sterile Human Drugs distributed between 11/21/2011 and 05/21/2012 because FDA … |
Source: FDA Enforcement Report (drug recalls) via openFDA, through October 8, 2026
What does the acetazolamide label say about other medicines?
The acetazolamide label names 1 other medicine in its interaction, contraindication or warning sections. The labels of 23 other medicines name acetazolamide. The sentences are the labels' own; a label lists what its studies and reports found, not every interaction.
| Medicine named | Section | What the label says |
|---|---|---|
| Aspirin | warnings | Caution is advised for patients receiving concomitant high-dose aspirin and acetazolamide, as anorexia, tachypnea, lethargy, metabolic acidosis, coma, and death have been reported. |
Other labels that name acetazolamide
Source: FDA drug label (Acetazolamide), Strides Pharma Science Limited, effective August 19, 2026 (SPL set 4813b9dd-5f58-44bb-ad64-cdb331828080), via openFDA; the full label on DailyMed
What do FAERS reports show for acetazolamide?
The FDA Adverse Event Reporting System holds 6,032 reports that list acetazolamide among the medicines taken, through July 30, 2026, each a report of something that happened, not proof the medicine caused it; 468 are coded as a death and 2,146 as a hospital stay. Counts follow how widely a medicine is used and watched, and they are not a measure of how risky it is.
Reports received each year
The most reported reactions
Source: FDA Adverse Event Reporting System (FAERS) via openFDA, reports through July 30, 2026
What next?
- Other carbonic anhydrase inhibitors
- the pharmacologic class, with prices and generics
- Acetazolamide side effects
- the label's list beside FAERS reports
- Check an interaction
- what two or more labels say about each other