Theo-24 XR Shortage Update: What Patients Need to Know in 2026

If you take Theo-24 XR (theophylline extended release) for asthma or COPD, you've likely noticed it's not always easy to find. This is not a temporary hiccup — it's an ongoing supply shortage that has affected patients since 2022, with some strengths remaining on back order as recently as late 2025.

Here's everything you need to know about the current shortage, including what strengths are most affected, what the FDA and manufacturers are doing, and your practical options right now.

Current Shortage Status (Early 2026)

As of early 2026, the ASHP (American Society of Health-System Pharmacists) maintains an active shortage listing for Theophylline 24-Hour Extended Release Capsules and Tablets. The listing was created in August 2023 and updated as recently as September 2025. Here is the breakdown by strength:

100 mg and 200 mg: More available than higher strengths, though spot shortages still occur at some pharmacies.

300 mg: Intermittently available; Alembic has listed some supply, but disruptions occur.

400 mg: Hardest to find. Both Glenmark and Rhodes have 400 mg on back order with no estimated release date. The Endo Pharmaceuticals Theo-24 400 mg capsules are also affected.

600 mg tablets: Glenmark also has 600 mg on back order.

The Glenmark Recall of August 2025

In August 2025, Glenmark initiated a market withdrawal of multiple batches of Theophylline Extended-Release Tablets 400 mg. The recall was triggered by dissolution test failures — meaning the tablets were not releasing the drug at the expected rate, which could lead to unpredictable blood levels. Failure results were found in 8 out of 27 tested batches within the shelf life, prompting a voluntary recall of all affected batches. This recall significantly tightened the 400 mg supply in late 2025.

Why Is There a Shortage?

The shortage stems from a long-term contraction in the manufacturing base for theophylline. Since 2010, every major brand-name version has been discontinued, leaving a handful of generic manufacturers to supply the entire market. For a detailed explanation, see our guide on why Theo-24 XR is so hard to find.

What Is the FDA Doing?

The FDA actively monitors drug shortages and works with manufacturers to resolve supply issues. Potential interventions include expediting review of new manufacturing applications, requesting that manufacturers ramp up production, and allowing temporary importation of approved foreign-source medications. However, for low-cost generics like theophylline, attracting new manufacturers is challenging because the financial incentives are limited.

Will the Shortage Resolve in 2026?

There is no confirmed timeline for full resolution. The structural factors driving the shortage — few manufacturers, thin margins, complex production requirements — are unlikely to change quickly. Some strengths and regions may see improved supply as manufacturers work through back orders, while others remain constrained. The best assumption is continued intermittent availability throughout 2026.

What Should Patients Do Right Now?

Here are the most important steps:

Refill early. Start your refill search 7 to 10 days before you run out. Most insurance plans allow a refill when you have about a week's supply left.

Use medfinder. Visit medfinder.com to find which pharmacies near you currently have your strength in stock. medfinder calls pharmacies on your behalf and sends results to your phone.

Talk to your doctor. Let your prescriber know about the supply situation. They may be able to write for a different available strength, authorize a manufacturer substitution, or discuss a transition to an alternative if shortages continue.

Try independent pharmacies. These often use different wholesalers than chain pharmacies and may have stock when the national chains don't.

Never stockpile. While the temptation is understandable, stockpiling worsens the shortage for other patients who depend on the same medication.

Is This Safe? Can I Just Stop Taking Theophylline?

Do not stop taking theophylline abruptly without talking to your doctor. If you have significant asthma or COPD, stopping your maintenance bronchodilator without a replacement could worsen your symptoms and increase your risk of an asthma attack or COPD exacerbation. Contact your prescriber as soon as you know you may run out.