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Acetazolamide 125 mg Tablet, 6-count — NDC 55289-720-06 (Billing 55289-0720-06)

by PD-Rx Pharmaceuticals, Inc. · 6 TABLET in 1 BOTTLE, PLASTIC

This is a package of 6 tablets of Acetazolamide 125 mg Tablet from PD-Rx Pharmaceuticals, Inc., no longer marketed (first marketed May 1997), no longer in the FDA NDC Directory. It is the main listing for this product, which comes in 2 package sizes.

NDC 55289-0720-06
🏷️ FDA NDC (as labeled) 55289-720-06 billing pads the product segment with a zero
This package
Contains6-count Pack sizes2 compare ↓
Also priced by: Part D plans $0.2706/unit — full pricing hub ↓
Main listing for product 55289-720 · Also comes in: 12 tablets 55289-720-12
Rx only Generic Discontinued Non-controlled ⚠ Discontinued by firm ⇄ Compare with another NDC
🗂️ FDA directory synced Oct 1, 2026 · this listing last changed Jul 24, 2026 · sources: openFDA · FDA label (DailyMed) · FDA Orange & Purple Book · First Databank · CMS NADAC, ASP, Medicare & Medicaid · RxNorm
📋 All sources & update times →
⚠️
Other active recalls for Acetazolamide (different manufacturers) — 1 · tap to view
These affect other manufacturers’ products for the same ingredient — not necessarily the exact NDC on this page.
Class III · Aug 24, 2024 — Discoloration (Rubicon Research Private Limited) · FDA recall D-0659-2024
Each entry is an official FDA enforcement report — look up any recall number in the FDA recall database ↗
⚠️
Excluded from the active FDA NDC Directory. The labeler reported this product as discontinued, so it is excluded from the active NDC Directory. The listing was last certified through Nov 2025. A label may still appear on DailyMed, but the NDC is no longer in the current FDA NDC Directory. Search the FDA NDC Directory ↗

Identity & classification

Regulatory identifiers FDA, NLM and CMS codes for this package

FDA NDC (as labeled) 55289-720-06
Product NDC 55289-720
11-digit billing NDC 55289072006
NCPDP billing unit EA — each (per item)
RxCUI 197303
UNII O3FX965V0I
Application # ANDA040195
SPL Set ID bd911de5-ea56-41ba-a328-20c8bfe7fe3b
Established class (EPC) Carbonic Anhydrase Inhibitor
Mechanism of action Carbonic Anhydrase Inhibitors
Chemical class Sulfonamides
DEA schedule Non-controlled
Marketing category ANDA
Marketing status Discontinued
FDA listing status Discontinued by firm (certified through Nov 2025)
Marketing start 1997-05-28
Route ORAL
Dosage form TABLET
Substance ACETAZOLAMIDE
TE code (Orange Book) AB · RLD · RS

Drug-database identifiers Medi-Span GPI and First Databank GCN / HICL / AHFS classification

GPI-14 37100010000305
GPI class acetaZOLAMIDE
GCN Seq No 008165
GCN 34721
HICL code 003641
Ingredient (HICL) Acetazolamide
HIC1 code R
Therapeutic class — broad (HIC1) Kidney/Urinary Tract
HIC2 code R1
Therapeutic class — intermediate (HIC2) Affect Primarily Kidneys/Urinary Tract
HIC3 code R1E
Therapeutic class — specific (HIC3) Carbonic Anhydrase Inhibitors
AHFS code 24:36.04.00
AHFS class Carbonic Anhydrase Inhibitors (24:36)
FDB label name ACETAZOLAMIDE 125 MG TABLET
FDB brand name Acetazolamide
Legend status F — Federal legend — prescription drug or device
Quick answers
  • GSN (GCN sequence number): 008165
  • GCN: 34721
  • GPI-14 (Medi-Span): 37100010000305
  • HICL (First Databank): 003641
  • AHFS class code: 24:36.04.00
  • RxCUI (RxNorm): 197303
Why two NDCs? The FDA registers this code as 55289-720-06 — a 5-3-2 layout, and that's what's printed on the package and shown on DailyMed. For insurance claims, every NDC is standardized to a uniform 11-digit 5-4-2 format by adding a zero to the product segment → 55289-0720-06. Same drug, same package — only the format differs.
Where does this data come from?
Identifiers from the FDA openFDA NDC Directory and Structured Product Labeling; RxCUI from RxNorm (NLM); GPI from Medi-Span; GCN / HIC / AHFS / legend from First Databank.

RxNorm drug class

This medicine belongs to the Carbonic Anhydrase Inhibitor class.

Pharmacologic class Carbonic Anhydrase Inhibitor
Drug family (ATC) Carbonic anhydrase inhibitors
How it works Carbonic Anhydrase Inhibitors
Where does this data come from?
Therapeutic classes from RxNorm RxClass (U.S. National Library of Medicine) — Established Pharmacologic Class (FDA), ATC drug family (WHO) and mechanism of action, matched by this product’s RxCUI.

Clinical

Label name ACETAZOLAMIDE 125 MG TABLET Ingredient Acetazolamide
📖 What it is MedlinePlus · NLM

Acetazolamide is used to treat glaucoma, a condition in which increased pressure in the eye can lead to gradual loss of vision. Acetazolamide decreases the pressure in the eye. Acetazolamide is also used to reduce the severity and duration of symptoms (upset stomach, headache, shortness of breath, dizziness, drowsiness, and fatigue) of altitude (mountain) sickness. Acetazolamide is used with other medicines to reduce edema (excess fluid retention) and to help control seizures in certain types of epilepsy. This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for...

Read the full MedlinePlus article ↗
📗 Our plain-language guide HelloPharmacist
  • It is used as an add-on treatment, most commonly for glaucoma. Depending on the product, it is also used for swelling from heart failure, certain seizure disorders, and preventing...
  • Tablets and capsules are taken by mouth, and the injection is given in a vein by a professional. Extended-release capsules for glaucoma are usually taken morning and evening. For m...
  • Tingling in fingers or face, more urination, tiredness, nausea, appetite or taste changes, and drowsiness are among the reported effects. Mention them if they bother you.
  • Call right away if you get a rash, blisters, fever, sore throat, unusual bruising, yellow skin or eyes, confusion, or swelling of the face. Acetazolamide is a sulfa-type drug, and...
📖 Read our full Acetazolamide guide →
8
Nutrient depletion considerations

Acetazolamide may be associated with lower levels of 8 nutrients — worth a chat with your pharmacist, not a cause for alarm.

An association is not a deficiency. Educational only — don't start or stop anything without professional guidance.
Where does this data come from?
Plain-language summary from MedlinePlus (U.S. National Library of Medicine); supplement & herbal interactions and nutrient depletion data from the Natural Medicines database; our full guide is HelloPharmacist editorial content.

Pricing

A drug doesn't have one price. Each row is a different public payment system, and none is what you'd pay at the counter — that depends on your insurance. The ⓘ on each row explains what it measures.

Price systemPer eachPer package
Retail pharmacies payNADAC · weekly Not in the retail survey — common for institutional, discontinued, or low-volume packs.
Medicaid paysCMS SDUD · 12 mo No recent Medicaid claims on file for this NDC — rare and low-volume NDCs are suppressed in the public data.
Medicare drug plans payPart D · Q2 2026 $0.2706 $1.62 / 6 tablets
Where does this data come from?
NADAC (National Average Drug Acquisition Cost) is the CMS weekly pharmacy-acquisition-cost survey — what pharmacies pay. ASP (Average Sales Price) is the CMS Medicare Part B drug-payment file, published quarterly. Medicaid pays is computed by us from CMS State Drug Utilization Data (total reimbursed ÷ units, trailing 12 months) — gross of rebates and inclusive of dispensing fees, so it reflects what Medicaid paid, not an acquisition cost. Medicare drug plans pay is the median negotiated point-of-sale unit cost across plans listing this NDC in the CMS quarterly Prescription Drug Plan pricing files, before rebates. The VA pays is the federal contract price (FSS, and the statutory Big 4 ceiling where listed) from the VA National Acquisition Center pharmaceutical price file. All are free public government data; each measures a different payer, so the figures are not directly comparable.

Packaging — all sizes for this product

Package NDCDescription Marketing startMarketing endStatus
55289-0720-06 You're viewing this Main listing 6 TABLET in 1 BOTTLE, PLASTIC 2016-03-03 — Discontinued by firm
55289-0720-12 55289-720-12 12 TABLET in 1 BOTTLE, PLASTIC 2016-03-03 — Discontinued by firm

You're viewing the smallest of 2 pack sizes for this product.

Pack size FAQ

What quantity is in this package?
This is a 6-count package — 6 tablet in 1 bottle, plastic.
How does this package differ from NDC 55289-0720-12?
Both are Acetazolamide 125 mg Tablet — the drug itself is identical. This page's package is the 6-count one, while NDC 55289-0720-12 is the 12 tablets package.
What NDC number is used to bill for this package of Acetazolamide 125 mg Tablet?
Use the 11-digit billing form listed in the identifiers section of this page. Pharmacy and medical claims use the 11-digit form; the FDA label may print a shorter form of the same code.

Therapeutic equivalents

ProductLabelerPackNADAC/unitTEStatusPrice vs. this
acetazolamide 125 mg 23155-0287-01 Heritage 100 tablets $0.096 AB Availability likely —
Acetazolamide 125 mg 59651-0905-01 Aurobindo 100 tablets $0.096 AB Availability likely —
Acetazolamide 125 mg 62135-0607-12 Chartwell 120 tablets $0.096 AB Availability likely —
Acetazolamide 125 mg 64380-0833-06 Strides 100 tablets $0.096 AB Availability likely —
Acetazolamide 125 mg 70756-0720-11 Lifestar 100 tablets $0.096 AB Availability likely —
Acetazolamide 125 mg 71930-0008-12 Eywa 100 tablets $0.096 AB Availability likely —
acetaZOLAMIDE 125 mg 72578-0149-01 Viona 100 tablets $0.096 AB Availability likely —
Acetazolamide 125 mg 72888-0047-01 Advagen 100 tablets $0.096 AB Availability likely —
Acetazolamide 125 mg 10135-0830-01 Marlex 100 tablets — AB FDA listed —
Acetazolamide 125 mg 27241-0132-04 Ajanta 100 tablets — — FDA listed —
acetazolamide 125 mg 42291-0089-01 AvKARE 100 tablets — AB FDA listed —
acetazolamide 125 mg 50090-5617-00 A-S 100 tablets — AB FDA listed —
acetazolamide 125 mg 51655-0331-52 Northwind 30 tablets — AB FDA listed —
Acetazolamide 125 mg 52817-0200-00 TRUPHARMA, 1000 tablets — AB FDA listed —
Acetazolamide 125 mgthis 55289-0720-06 PD-Rx 6 tablets — AB Discontinued —
Acetazolamide 125 mg 63629-1194-01 Bryant 100 tablets — AB FDA listed —
Acetazolamide 125 mg 68071-3550-01 NuCare 12 tablets — AB FDA listed —
acetaZOLAMIDE 125 mg 68071-3632-01 NuCare 100 tablets — AB FDA listed —
Acetazolamide 125 mg 68071-3728-01 NuCare 12 tablets — AB FDA listed —
acetaZOLAMIDE 125 mg 70710-1238-01 Zydus 100 tablets — AB FDA listed —
acetaZOLAMIDE 125 mg 70771-1827-01 Zydus 100 tablets — AB FDA listed —
Acetazolamide 125 mg 70954-0033-20 ANI 1000 tablets — AB FDA listed —
Acetazolamide 125 mg 71205-0308-30 Proficient 30 tablets — AB FDA listed —
Acetazolamide 125 mg 72162-1978-01 Bryant 100 tablets — AB FDA listed —
Acetazolamide 125 mg 72789-0045-06 PD-Rx 6 tablets — AB FDA listed —
Acetazolamide 125 mg 72789-0238-01 PD-Rx 100 tablets — AB FDA listed —
Acetazolamide 125 mg 81005-0104-01 Aarkish 100 tablets — AB FDA listed —
About this product: this is a generic version of the medicine. FDA equivalence ratings are shown when available, and other versions are listed above, least expensive first.
Where does this data come from?
Equivalents are other NDCs of the same ingredient, form and route from the openFDA NDC Directory, ranked least-expensive-first by NADAC. Therapeutic-equivalence (AB) ratings come from the FDA Orange Book; biologics use the FDA Purple Book for biosimilar & interchangeable status.

Availability & generic status

🏛️
1997
On the market since
May 1997
📍
2026
Currently FDA-listed
29 years listed
🔓
·
Generic on the market
this product is a generic
✅This is a generic drug

This product is an FDA-approved generic. Other versions of the same drug are listed under Therapeutic equivalents, least expensive first.

Where does this data come from?
Patents and exclusivity from the FDA Orange Book (small-molecule drugs), refreshed from public FDA data. Generic launch timing is an estimate, not a guarantee.

Inactive Ingredients / Excipients

Inactive ingredients, also called excipients, are components of the drug product other than the active ingredient. They may include fillers, dyes, coatings, preservatives, flavors, or other formulation ingredients.

Loading inactive ingredients from the official FDA label in the background. No external source is being called by this page request.
Where does this data come from?
Source: official FDA Structured Product Labeling (SPL) via DailyMed and the openFDA label index. Structured IACT rows and label-wide narrative are kept separate; availability and product-level specificity depend on the submitted label.

Inactive ingredient FAQ

Are inactive ingredients the same for every manufacturer?
No. Inactive ingredients can differ by manufacturer, dosage form, strength, and package / product version.
Why might an inactive ingredient be missing?
Some SPLs do not provide a complete structured inactive-ingredient list, and older or unusual labels may only include the information in narrative text.
Can inactive ingredients matter?
Yes. They can matter for allergies, intolerances, dyes, gluten / lactose concerns, preservatives, and formulation differences — but confirm with a pharmacist or the manufacturer when it’s clinically important.

Manufacturer & labeler

LabelerPD-Rx Pharmaceuticals, Inc.
Application holderTARO PHARMACEUTICAL INDUSTRIES LTD
FDA applicationANDA040195 (ANDA)
Labeler code55289
First marketedMay 1997
Product typeHuman Prescription Drug
Portfolio834 products on file
The labeler markets the product; the application holder owns the FDA approval. They’re often the same company but can differ (e.g. a repackager or an authorized generic). A mailing address / phone appears here when the manufacturer includes it in the product’s FDA label (not all do).
Where does this data come from?
Labeler, application holder and registered establishment from the FDA openFDA NDC Directory and Drugs@FDA; address/contact from the product’s FDA label.

Full prescribing information FDA SPL

The complete FDA label for this product — the official prescribing information, verbatim, section by section. Jump with a chip, search within the label, or expand everything.
🎯 Indications and Usage 81 words ▾

INDICATIONS AND USAGE For 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.

⏱️ Dosage and Administration ~3 min read ▾

DOSAGE AND ADMINISTRATION Glaucoma Acetazolamide should be used as an adjunct to the usual therapy. The dosage employed in the treatment of chronic simple (open-angle) glaucoma ranges from 250 mg to 1 g of acetazolamide per 24 hours, usually in divided doses for amounts over 250 mg. It has usually been found that a dosage in excess of 1 g per 24 hours does not produce an increased effect.

In all cases, the dosage should be adjusted with careful individual attention both to symptomatology and ocular tension. Continuous supervision by a physician is advisable. In treatment of secondary glaucoma and in the preoperative treatment of some cases of acute congestive (closed-angle) glaucoma , the preferred dosage is 250 mg every four hours, although some cases have responded to 250 mg twice daily on short-term therapy.

In some acute cases, it may be more satisfactory to administer an initial dose of 500 mg followed by 125 mg or 250 mg every four hours depending on the individual case. A complementary effect has been noted when acetazolamide has been used in conjunction with miotics or mydriatics as the case demanded. Epilepsy It is not clearly known whether the beneficial effects observed in epilepsy are due to direct inhibition of carbonic anhydrase in the central nervous system or whether they are due to the slight degree of acidosis produced by the divided dosage.

The best results to date have been seen in petit mal in children. Good results, however, have been seen in patients, both children and adult, in other types of seizures such as grand mal, mixed seizure patterns, myoclonic jerk patterns, etc. The suggested total daily dose is 8 to 30 mg per kg in divided doses.

Although some patients respond to a low dose, the optimum range appears to be from 375 to 1000 mg daily. However, some investigators feel that daily doses in excess of 1 g do not produce any better results than a 1 g dose. When acetazolamide tablets are given in combination with other anticonvulsants, it is suggested that the starting dose should be 250 mg once daily in addition to the existing medications.

This can be increased to levels as indicated above. The change from other medications to acetazolamide should be gradual and in accordance with usual practice in epilepsy therapy. Congestive Heart Failure For diuresis in congestive heart failure, the starting dose is usually 250 to 375 mg once daily in the morning (5 mg/kg).

If, after an initial response, the patient fails to continue to lose edema fluid, do not increase the dose but allow for kidney recovery by skipping medication for a day. Acetazolamide tablets yield best diuretic results when given on alternate days, or for two days alternating with a day of rest. Failures in therapy may be due to overdosage or too frequent dosage.

The use of acetazolamide does not eliminate the need for other therapy such as digitalis, bed rest, and salt restriction. Drug-Induced Edema Recommended dosage is 250 to 375 mg of acetazolamide once a day for one or two days, alternating with a day of rest. Acute Mountain Sickness Dosage is 500 mg to 1000 mg daily, in divided doses.

In circumstances of rapid ascent, such as in rescue or military operations, the higher dose level of 1000 mg is recommended. It is preferable to initiate dosing 24 to 48 hours before ascent and to continue for 48 hours while at high altitude, or longer as necessary to control symptoms. Note: The dosage recommendations for glaucoma and epilepsy differ considerably from those for congestive heart failure, since the first two conditions are not dependent upon carbonic anhydrase inhibition in the kidney which requires intermittent dosage if it is to recover from the inhibitory effect of the therapeutic agent.

⛔ Contraindications 85 words ▾

CONTRAINDICATIONS Acetazolamide therapy is contraindicated in situations in which sodium and/or potassium blood serum levels are depressed, in cases of marked kidney and liver disease or dysfunction, in suprarenal gland failure, and in hyperchloremic acidosis. It is contraindicated in patients with cirrhosis because of the risk of development of hepatic encephalopathy. Long-term administration of acetazolamide is contraindicated in patients with chronic non-congestive angle-closure glaucoma since it may permit organic closure of the angle to occur while the worsening glaucoma is masked by lowered intraocular pressure.

⚠️ Warnings 77 words ▾

WARNINGS Fatalities have occurred, although rarely, due to severe reactions to sulfonamides including Stevens-Johnson syndrome, toxic epidermal necrolysis, fulminant hepatic necrosis, agranulocytosis, aplastic anemia, and other blood dyscrasias. Sensitizations may recur when a sulfonamide is readministered irrespective of the route of administration. If signs of hypersensitivity or other serious reactions occur, discontinue use of this drug.

Caution is advised for patients receiving concomitant high-dose aspirin and acetazolamide, as anorexia, tachypnea, lethargy, coma and death have been reported.

🤒 Adverse Reactions 127 words ▾

ADVERSE REACTIONS Adverse reactions, occurring most often early in therapy, include paresthesias, particularly a "tingling" feeling in the extremities, hearing dysfunction or tinnitus, loss of appetite, taste alteration and gastrointestinal disturbances such as nausea, vomiting and diarrhea, polyuria, and occasional instances of drowsiness and confusion. Metabolic acidosis and electrolyte imbalance may occur. Transient myopia has been reported.

This condition invariably subsides upon diminution or discontinuance of the medication. Other occasional adverse reactions include urticaria, melena, hematuria, glycosuria, hepatic insufficiency, flaccid paralysis, photosensitivity and convulsions. Also see PRECAUTIONS: Information for Patients for possible reactions common to sulfonamide derivatives.

Fatalities have occurred although rarely, due to severe reactions to sulfonamides including Stevens-Johnson syndrome, toxic epidermal necrolysis, fulminant hepatic necrosis, agranulocytosis, aplastic anemia and other blood dyscrasias (see WARNINGS ).

🤰 Pregnancy 55 words ▾

Pregnancy Teratogenic Effect Pregnancy Category C Acetazolamide, administered orally or parenterally, has been shown to be teratogenic (defects of the limbs) in mice, rats, hamsters and rabbits. There are no adequate and well-controlled studies in pregnant women. Acetazolamide should be used in pregnancy only if the potential benefit justifies the potential risk to the fetus.

🧒 Pediatric Use 15 words ▾

Pediatric Use The safety and effectiveness of acetazolamide in pediatric patients has not been established.

🆘 Overdosage 124 words ▾

OVERDOSAGE No data are available regarding acetazolamide overdosage in humans as no cases of acute poisoning with this drug have been reported. Animal data suggest that acetazolamide is remarkably nontoxic. No specific antidote is known.

Treatment should be symptomatic and supportive. Electrolyte imbalance, development of an acidotic state, and central nervous effects might be expected to occur. Serum electrolyte levels (particularly potassium) and blood pH levels should be monitored.

Supportive measures are required to restore electrolyte and pH balance. The acidotic state can usually be corrected by the administration of bicarbonate. Despite its high intraerythrocytic distribution and plasma protein binding properties, acetazolamide may be dialyzable.

This may be particularly important in the management of acetazolamide overdosage when complicated by the presence of renal failure.

🧬 Clinical Pharmacology ~2 min read ▾

CLINICAL PHARMACOLOGY Acetazolamide is a potent carbonic anhydrase inhibitor, effective in the control of fluid secretion (e.g., some types of glaucoma), in the treatment of certain convulsive disorders (e.g., epilepsy), and in the promotion of diuresis in instances of abnormal fluid retention (e.g., cardiac edema). Acetazolamide is not a mercurial diuretic. Rather, it is a nonbacteriostatic sulfonamide possessing a chemical structure and pharmacological activity distinctly different from the bacteriostatic sulfonamides.

Acetazolamide is an enzyme inhibitor that acts specifically on carbonic anhydrase, the enzyme that catalyzes the reversible reaction involving the hydration of carbon dioxide and the dehydration of carbonic acid. In the eye, this inhibitory action of acetazolamide decreases the secretion of aqueous humor and results in a drop in intraocular pressure, a reaction considered desirable in cases of glaucoma and even in certain nonglaucomatous conditions. Evidence seems to indicate that acetazolamide has utility as an adjuvant in the treatment of certain dysfunctions of the central nervous system (e.g., epilepsy).

Inhibition of carbonic anhydrase in this area appears to retard abnormal, paroxysmal, excessive discharge from central nervous system neurons. The diuretic effect of acetazolamide is due to its action in the kidney on the reversible reaction involving hydration of carbon dioxide and dehydration of carbonic acid. The result is renal loss of HCO 3 ion, which carries out sodium, water, and potassium.

Alkalinization of the urine and promotion of diuresis are thus affected. Alteration in ammonia metabolism occurs due to increased reabsorption of ammonia by the renal tubules as a result of urinary alkalinization. Placebo-controlled clinical trials have shown that prophylactic administration of acetazolamide at a dose of 250 mg every eight to 12 hours (or a 500 mg controlled-release capsule once daily) before and during rapid ascent to altitude results in fewer and/or less severe symptoms (such as headache, nausea, shortness of breath, dizziness, drowsiness, and fatigue) of acute mountain sickness (AMS).

Pulmonary function (e.g., minute ventilation, expired vital capacity and peak flow) is greater in the acetazolamide treated group, both in subjects with AMS and asymptomatic subjects. The acetazolamide treated climbers also had less difficulty in sleeping.

📦 How Supplied / Storage and Handling 49 words ▾

HOW SUPPLIED Acetazolamide Tablets USP are supplied as follows: 125 mg - White, round, scored in half, on one side, "T52" engraved on the other side. NDC 55289-720-06 Bottle of 6 NDC 55289-720-12 Bottle of 12 Store at 20° to 25°C (68° to 77°F) [see USP Controlled Room Temperature].

📦 Storage and Handling 13 words ▾

Store at 20° to 25°C (68° to 77°F) [see USP Controlled Room Temperature].

📋 Description 97 words ▾

DESCRIPTION Acetazolamide, an inhibitor of the enzyme carbonic anhydrase, is a white to faintly yellowish white crystalline, odorless powder, weakly acidic, very slightly soluble in water and slightly soluble in alcohol. The chemical name for acetazolamide is N -(5-Sulfamoyl-1,3,4-thiadiazol-2-yl)-acetamide and has the following chemical structure: Molecular Weight: 222.25 Molecular Formula: C 4 H 6 N 4 O 3 S 2 Acetazolamide is available as oral tablets containing 125 mg and 250 mg of acetazolamide, respectively, and the following inactive ingredients: corn starch, gelatin, glycerin, lactose monohydrate, magnesium stearate, purified water, sodium starch glycolate and talc.

Chemical Structure

💬 Information for Patients 160 words ▾

Information for Patients Adverse reactions common to all sulfonamide derivatives may occur: anaphylaxis, fever, rash (including erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis), crystalluria, renal calculus, bone marrow depression, thrombocytopenic purpura, hemolytic anemia, leukopenia, pancytopenia and agranulocytosis. Precaution is advised for early detection of such reactions and the drug should be discontinued and appropriate therapy instituted. In patients with pulmonary obstruction or emphysema where alveolar ventilation may be impaired, acetazolamide, which may precipitate or aggravate acidosis, should be used with caution.

Gradual ascent is desirable to try to avoid acute mountain sickness. If rapid ascent is undertaken and acetazolamide tablets are used, it should be noted that such use does not obviate the need for prompt descent if severe forms of high altitude sickness occur, i.e., high altitude pulmonary edema (HAPE) or high altitude cerebral edema. Caution is advised for patients receiving concomitant high-dose aspirin and acetazolamide, as anorexia, tachypnea, lethargy, coma and death have been reported (see WARNINGS ).

⚠️ Precautions ~2 min read ▾

PRECAUTIONS General Increasing the dose does not increase the diuresis and may increase the incidence of drowsiness and/or paresthesia. Increasing the dose often results in a decrease in diuresis. Under certain circumstances, however, very large doses have been given in conjunction with other diuretics in order to secure diuresis in complete refractory failure.

Information for Patients Adverse reactions common to all sulfonamide derivatives may occur: anaphylaxis, fever, rash (including erythema multiforme, Stevens-Johnson syndrome, toxic epidermal necrolysis), crystalluria, renal calculus, bone marrow depression, thrombocytopenic purpura, hemolytic anemia, leukopenia, pancytopenia and agranulocytosis. Precaution is advised for early detection of such reactions and the drug should be discontinued and appropriate therapy instituted. In patients with pulmonary obstruction or emphysema where alveolar ventilation may be impaired, acetazolamide, which may precipitate or aggravate acidosis, should be used with caution.

Gradual ascent is desirable to try to avoid acute mountain sickness. If rapid ascent is undertaken and acetazolamide tablets are used, it should be noted that such use does not obviate the need for prompt descent if severe forms of high altitude sickness occur, i.e., high altitude pulmonary edema (HAPE) or high altitude cerebral edema. Caution is advised for patients receiving concomitant high-dose aspirin and acetazolamide, as anorexia, tachypnea, lethargy, coma and death have been reported (see WARNINGS ).

Laboratory Tests To monitor for hematologic reactions common to all sulfonamides, it is recommended that a baseline CBC and platelet count be obtained on patients prior to initiating acetazolamide tablet therapy and at regular intervals during therapy. If significant changes occur, early discontinuance and institution of appropriate therapy are important. Periodic monitoring of serum electrolytes is recommended.

Carcinogenesis, Mutagenesis, Impairment of Fertility Long-term studies in animals to evaluate the carcinogenic potential of acetazolamide have not been conducted. In a bacterial mutagenicity assay, acetazolamide was not mutagenic when evaluated with and without metabolic activation. The drug had no effect on fertility when administered in the diet to male and female rats at a daily intake of up to 4 times the recommended human dose of 1000 mg in a 50 kg individual.

Pregnancy Teratogenic Effect Pregnancy Category C Acetazolamide, administered orally or parenterally, has been shown to be teratogenic (defects of the limbs) in mice, rats, hamsters and rabbits. There are no adequate and well-controlled studies in pregnant women. Acetazolamide should be used in pregnancy only if the potential benefit justifies the potential risk to the fetus.

Nursing Mothers Because of the potential for serious adverse reaction in nursing infants from acetazolamide, a decision should be made whether to discontinue nursing or to discontinue the drug taking into account the importance of the drug to the mother. Pediatric Use The safety and effectiveness of acetazolamide in pediatric patients has not been established.

🍼 Nursing Mothers 40 words ▾

Nursing Mothers Because of the potential for serious adverse reaction in nursing infants from acetazolamide, a decision should be made whether to discontinue nursing or to discontinue the drug taking into account the importance of the drug to the mother.

📄 Carcinogenesis, Mutagenesis, Impairment of Fertility 74 words ▾

Carcinogenesis, Mutagenesis, Impairment of Fertility Long-term studies in animals to evaluate the carcinogenic potential of acetazolamide have not been conducted. In a bacterial mutagenicity assay, acetazolamide was not mutagenic when evaluated with and without metabolic activation. The drug had no effect on fertility when administered in the diet to male and female rats at a daily intake of up to 4 times the recommended human dose of 1000 mg in a 50 kg individual.

📄 Package Label / Principal Display Panel 29 words ▾

PRINCIPAL DISPLAY PANEL - 125 mg Tablet Bottle Label AcetaZOLAMIDE Tablets USP, 125 mg Keep this and all medications out of the reach of children. Rx only 55289720 Label

Source: FDA Structured Product Labeling, mirrored from DailyMed / openFDA. Prefer the government’s original formatting? View this label on DailyMed ↗

Medicare Part D spend CMS · PART D · 2026 (Q1)

Medicare Part D (outpatient prescription) spending for Acetazolamide — the program that covers self-administered drugs. 12 manufacturers.
⚠️ Drug-level data: CMS publishes Part D spending by drug, not by NDC — these figures combine every manufacturer, strength and package size sold under the name Acetazolamide. That’s a different level of aggregation than the Medicaid card above, which is specific to this exact 11-digit NDC (pack size included), so the two aren’t directly comparable.
Period
Total Part D spend
$2.17M
Claims incl. refills
65K
Beneficiaries
44.5K
Spend / beneficiary
$48.76
Spend / claim
$33.33
Trend by period
💵 About the dollar figures: spending is what Part D plans paid before confidential manufacturer rebates, so the program’s real net cost is lower. A blank patient count means fewer than 11 people — CMS hides counts that small to protect privacy. Source: CMS Medicare Quarterly Part D Spending by Drug (data.cms.gov), updated quarterly.

About this NDC listing & data coverage

Finished prescription product No longer marketed (per FDA listing data)
What data is (and isn’t) available for this NDC — tap to expand
NDC identity (package / product / labeler codes) ✓ Available
Labeler ✓ Available
Product & package description ✓ Available
Marketing category & status ✓ Available
Active ingredient / dosage form / route ✓ Available
FDA label (SPL via DailyMed) ✓ Available
Package photos — Not published for this NDC No photo available yet for this listing.
Inactive ingredients (structured) — Not published for this NDC The labeler did not submit a structured excipient list, or no SPL is available.
NADAC pharmacy acquisition price (CMS) — Not published for this NDC CMS publishes NADAC only for NDCs reported in its retail-pharmacy survey.
Orange Book / therapeutic-equivalence data ✓ Available
HCPCS J-code billing crosswalk — Not published for this NDC Most self-administered / retail products have no J-code — that is normal.
Medicaid utilization (CMS SDUD) — Not published for this NDC CMS reports utilization only for NDCs with Medicaid claims above its privacy threshold.
“Not published” reflects what the public FDA / CMS / NLM sources provide for this exact package code — it is a property of the data feeds, not a judgment about the product.

Questions about this listing

Why is there no price listed?
The pricing shown on our NDC pages comes from CMS NADAC, a voluntary survey of retail community pharmacy invoices. CMS does not publish a NADAC for every NDC — packages outside the retail survey (institutional and hospital products, bulk packages, discontinued items, and many OTC items) may never receive one. A missing price reflects the survey's scope, not this product's actual cost, and does not mean the product is free or unavailable.
What does the discontinued status mean for this NDC?
The labeler reported a marketing end date (or the listing was delisted), so this specific package is no longer actively marketed. Remaining stock may still be dispensed for a time, and the NDC stays valid for historical records and claims — but data feeds (pricing, labeling) typically stop updating for it. Other package sizes or other manufacturers' versions of the same medication may still be marketed — see the equivalents section where available.
Is the NDC printed on the package the same as the 11-digit billing NDC?
Yes, they identify this exact package in different formats. The form printed on the packaging and shown on DailyMed is the one the FDA registered. Insurance claims use a fixed 11-digit 5-4-2 format, so the short segment is padded with a leading zero and the dashes are dropped. The Identity section at the top of this page lists each form of this code.
Does this product come in other package sizes?
Yes — the FDA directory lists 1 other package presentation of this same product, including 12 tablets (55289-0720-12). Each has its own NDC and its own page — see the package list near the top of this page.
Who lists this product with the FDA?
PD-Rx Pharmaceuticals, Inc. is the labeler of record for this NDC — the company under whose FDA-assigned code the package is listed. The labeler may be the manufacturer itself or a distributor marketing the product under its own code.
Do I need a prescription for this product?
This NDC is listed with FDA as a prescription product, so it is dispensed under a prescriber's order. Your pharmacist can tell you whether any over-the-counter forms of the same medication exist.
This page identifies an FDA-listed package (the NDC) and reports public regulatory and pricing data about the listing. It is reference information, not a medical recommendation — talk to your pharmacist or prescriber about your own medication.
Where does this data come from?
Listing facts (marketing category, packager status, marketing dates) from the FDA openFDA NDC Directory; label availability from DailyMed; pricing coverage from CMS NADAC; equivalence scope from the FDA Orange Book.
For educational and professional reference only — not medical advice. Pricing reflects published NADAC and CMS ASP (free public data) and may differ from your acquisition cost; always verify before billing or dispensing.