Is acetazolamide out of stock? A detailed look at supply chain issues
The supply status of acetazolamide is complex and often depends on the specific formulation and manufacturer. While global shortages have been documented over the years, the current situation highlights specific issues impacting different product types. As of late 2025, reports from official sources like the ASHP and regulatory bodies in Canada indicate ongoing shortages affecting some acetazolamide products.
The current status of acetazolamide supply
- Injectable formulation shortages: The most recent and persistent shortages appear to be concentrated in the injectable form of acetazolamide sodium. As of September 2025, manufacturers like Avet and Hikma have reported shortages of the 500-mg, 1-count vials of lyophilized powder for injection. Reasons for these injectable shortages can range from manufacturing delays to raw material procurement problems.
- Oral tablet availability: The supply of immediate-release oral acetazolamide tablets (125 mg and 250 mg) is generally more robust. While isolated shortages have occurred in the past, generic manufacturers have largely maintained production. For example, a report from April 2025 in Canada noted a resolved shortage of AA Pharma's acetazolamide 250 mg tablets, indicating that supply can fluctuate but often recovers.
- Discontinuation of modified-release capsules: Patients who previously used the modified-release (SR) capsules should be aware that these have been widely discontinued. The brand-name equivalent, Diamox SR 250mg, is no longer produced, with some reports noting its discontinuation as far back as 2023.
- Brand-name discontinuation: The brand-name product Diamox has been formally discontinued by its manufacturer in various markets, including the U.S., for non-safety-related reasons. This means patients are now primarily reliant on generic formulations of acetazolamide.
Why do drug shortages happen?
Drug shortages, including those for acetazolamide, result from a variety of systemic and specific factors:
- Manufacturing problems: Issues can arise at any point in the manufacturing process, from raw material sourcing to quality control. Past recalls due to contamination, such as a 2016 recall in Australia, demonstrate the potential for manufacturing issues to disrupt supply.
- Supply chain disruptions: A globalized supply chain means that issues in one part of the world can affect availability everywhere. Geopolitical events, logistical challenges, and natural disasters can all impact the consistent flow of materials and finished products.
- Market economics: The economics of generic drug manufacturing can lead to shortages. For example, a 2025 analysis noted that low reimbursement prices can make some older, off-patent drugs unprofitable for pharmacies to dispense, disincentivizing supply.
- Regulatory changes: Evolving regulatory requirements and inspections can temporarily halt production at facilities until compliance is achieved. Changes in regulations have also led to the discontinuation of specific formulations, like the extended-release capsules.
Alternatives and management strategies for patients
When a specific formulation of acetazolamide is unavailable, patients should work closely with their healthcare team to find an appropriate solution. Strategies may include:
- Switching formulations: If a patient was on a modified-release capsule, their doctor might switch them to an immediate-release tablet with a different dosing schedule. A dose adjustment may be necessary.
- Exploring alternative medications: For some conditions, particularly glaucoma, other medications are available. For example, prostaglandin analogues or beta-blockers might be used. For altitude sickness, patients might use alternative strategies or a different prophylactic medication as recommended by a specialist.
- Sourcing from a different manufacturer: With generic acetazolamide having multiple manufacturers, a specific pharmacy might be out of stock from one supplier but able to get it from another. Patients and pharmacists can work together to check different distributors.
- Considering compounding pharmacies: In some cases, a compounding pharmacy may be able to prepare an oral suspension or a custom formulation, especially if a specific dose or delivery method is required. For instance, in the UK, special manufacturers sourced unlicensed acetazolamide SR 250mg capsules to mitigate the shortage.
Comparison of Acetazolamide Formulations and Alternatives
| Feature | Immediate-Release Tablets | Modified-Release (SR) Capsules | Acetazolamide Injection | Alternative Diuretics | Non-Pharmacological Alternatives |
|---|---|---|---|---|---|
| Availability | Generally available from multiple generic manufacturers. | Discontinued in many regions (e.g., Diamox SR). | Subject to current and historical shortages. | Variable availability, but usually accessible. | Always available. |
| Dosing Frequency | Typically requires twice-daily or more frequent dosing. | Designed for less frequent dosing (e.g., twice daily). | Used for acute, emergent situations. | Varies by medication (e.g., loop diuretics). | Lifestyle and behavioral changes. |
| Use Case | Glaucoma, altitude sickness, certain epilepsies. | Formerly used for various chronic conditions. | Acute angle-closure glaucoma, emergent high intraocular pressure. | Heart failure (loop diuretics), edema. | Gradual ascent (altitude sickness), lifestyle changes (glaucoma). |
| Brand Name | Formerly Diamox, now primarily generic. | Formerly Diamox SR, now discontinued. | Formerly Diamox, now generic. | Various (e.g., Furosemide, Bumetanide). | N/A |
Navigating the shortage: a patient and provider guide
With ongoing fluctuations in the supply chain, communication between patients and healthcare providers is critical. Patients should be proactive by calling their pharmacy in advance of needing a refill to confirm stock. They should also inquire about the specific manufacturer or supplier. Healthcare providers, for their part, must stay abreast of the latest drug shortage updates from authoritative sources like the FDA and ASHP.
For conditions requiring uninterrupted treatment, such as glaucoma or specific types of epilepsy, it is vital to have a contingency plan in place. This may involve discussing with a specialist potential alternative treatments that have a more reliable supply chain or exploring different dosing strategies with currently available oral tablets. This proactive approach helps ensure patients receive consistent care despite potential shortages of specific formulations.
Conclusion
While the answer to is acetazolamide out of stock? is not a simple "yes" or "no," it is clear that specific formulations, particularly the injectable and modified-release versions, are facing significant and ongoing supply challenges. The brand-name version, Diamox, is also largely discontinued, with reliance on generic versions. While oral tablets are generally more available, shortages can occur intermittently. Patients should maintain open communication with their healthcare providers and pharmacists to monitor supply and explore alternatives when necessary. Understanding the nuances of the drug supply landscape is essential for effective medication management and continuity of care.
