What it's used for
Theophylline is used to treat symptoms and reversible airflow obstruction associated with chronic asthma and other chronic lung diseases like emphysema and chronic bronchitis.
Source: U.S. FDA-approved prescribing information (openFDA).
Typical dosing
Extended-release tablets of 400 or 600 mg can be taken once daily in the morning or evening, and are recommended to be taken with meals.
Dosing shown here is the general FDA-labeled range. Your prescribing clinician determines the exact dose, form, and schedule for you — this is not a substitute for medical advice.
Boxed warning / key safety info
Theophylline should be used with extreme caution in patients with active peptic ulcer disease, seizure disorders, or certain cardiac arrhythmias due to the risk of worsening these conditions.
Common side effects
Mild side effects at lower concentrations include nausea, vomiting, headache, and insomnia, while higher concentrations can cause severe effects like persistent vomiting, heart rhythm problems, and seizures.
Covered strengths on the Tab $0 list
Covered at $0 with an active Tab membership when filled at a participating pharmacy nationwide or through mail order. A licensed clinician must prescribe the medication.
Related medications
Other asthma & respiratory medications covered at $0 with an active Tab membership.
Theophylline Anhydrous cost without insurance
Cash prices for Theophylline Anhydrous without insurance vary widely by pharmacy, strength and quantity — the same prescription can cost very different amounts at two pharmacies in the same town. That is the problem a membership solves.
Theophylline Anhydrous is on Tab's covered $0 generic list. With an active Tab membership, every covered strength is $0 — not a percentage off, not a coupon that changes month to month — at participating pharmacies nationwide or through mail order. You do not need insurance, and Tab works whether or not you have a health plan.
Tab is a membership, not insurance. Covered medications require a prescription from a licensed clinician.
Theophylline Anhydrous dosage and administration
Theophylline (Anhydrous) Extended-Release Tablets 400 or 600 mg can be taken once a day in the morning or evening. It is recommended that Theophylline (Anhydrous) Extended-Release Tablets be taken with meals. Patients should be advised that if they choose to take Theophylline (Anhydrous) Extended-Release Tablets with food it should be taken consistently with food and if they take it in a fasted condition it should routinely be taken fasted. It is important that the product whenever dosed be dosed consistently with or without food. Theophylline (Anhydrous) Extended-Release Tablets are not to be chewed or crushed because it may lead to a rapid release of theophylline with the potential for toxicity. The scored tablet may be split.
Excerpt from the FDA-approved prescribing information (openFDA), retrieved 2026-09-15. Your prescribing clinician decides the exact dose, form and schedule for you — this is not medical advice.
Theophylline Anhydrous side effects
Adverse reactions associated with theophylline are generally mild when peak serum theophylline concentrations are <20 mcg/mL and mainly consist of transient caffeine-like adverse effects such as nausea, vomiting, headache and insomnia. When peak serum theophylline concentrations exceed 20 mcg/mL, however, theophylline produces a wide range of adverse reactions including persistent vomiting, cardiac arrhythmias, and intractable seizures which can be lethal (see OVERDOSAGE ). The transient caffeine-like adverse reactions occur in about 50% of patients when theophylline therapy is initiated at doses higher than recommended initial doses (e.g., >300 mg/day in adults and >12 mg/kg/day in children beyond >1 year of age).
Excerpt from the FDA-approved prescribing information (openFDA), retrieved 2026-09-15. This is not a complete list. Report side effects to your clinician, and seek care for anything severe or unexpected.
Theophylline Anhydrous drug interactions
Theophylline interacts with a wide variety of drugs. The interaction may be pharmacodynamic, i.e., alterations in the therapeutic response to theophylline or another drug or occurrence of adverse effects without a change in serum theophylline concentration. More frequently, however, the interaction is pharmacokinetic, i.e., the rate of theophylline clearance is altered by another drug resulting in increased or decreased serum theophylline concentrations. Theophylline only rarely alters the pharmacokinetics of other drugs. The drugs listed in Table II have the potential to produce clinically significant pharmacodynamic or pharmacokinetic interactions with theophylline. The information in the "Effect" column of Table II assumes that the interacting drug is being added to a steady-state theophylline regimen.
Excerpt from the FDA-approved prescribing information (openFDA), retrieved 2026-09-15. Tell your clinician and pharmacist about every medication, supplement and over-the-counter product you take.
Who should not take theophylline anhydrous
Theophylline (Anhydrous) Extended-Release Tablets are contraindicated in patients with a history of hypersensitivity to theophylline or other components in the product.
Excerpt from the FDA-approved prescribing information (openFDA), retrieved 2026-09-15. Whether this medication is appropriate for you is a clinical decision made by your prescribing clinician.
Common questions
Is theophylline Anhydrous covered at $0 with Tab?
Yes. Theophylline Anhydrous is on Tab's covered $0 generic list — every covered strength is $0 with an active membership, at participating pharmacies nationwide or by mail order.
Do I need insurance to get theophylline Anhydrous through Tab?
No. Tab is a membership, not insurance. Covered medications are $0 with an active membership whether or not you have a health plan.
How do I get a theophylline Anhydrous prescription with Tab?
Book a video visit with a licensed Tab clinician (unlimited visits are included with membership). If it's clinically appropriate, they send the prescription to your chosen participating pharmacy or by mail order.
How much does theophylline anhydrous cost without insurance?
Without insurance, retail cash prices for theophylline anhydrous vary by pharmacy, strength and quantity. Theophylline Anhydrous is on Tab's covered $0 generic list, so every covered strength is $0 with an active Tab membership at participating pharmacies nationwide or by mail order.
What is the cheapest way to get theophylline anhydrous?
For medications on Tab's covered list, a Tab membership is the cheapest route: covered strengths of theophylline anhydrous are $0 with an active membership, and unlimited video visits with a licensed clinician are included, so the visit that produces the prescription is covered too.
What is the usual dose of theophylline anhydrous?
Theophylline (Anhydrous) Extended-Release Tablets 400 or 600 mg can be taken once a day in the morning or evening. It is recommended that Theophylline (Anhydrous) Extended-Release Tablets be taken with meals. (FDA-approved label, retrieved 2026-09-15. Your clinician sets your dose.)
What are the side effects of theophylline anhydrous?
Adverse reactions associated with theophylline are generally mild when peak serum theophylline concentrations are <20 mcg/mL and mainly consist of transient caffeine-like adverse effects such as nausea, vomiting, headache and insomnia. (FDA-approved label, retrieved 2026-09-15.)
What interacts with theophylline anhydrous?
Theophylline interacts with a wide variety of drugs. The interaction may be pharmacodynamic, i.e., alterations in the therapeutic response to theophylline or another drug or occurrence of adverse effects without a change in serum theophylline concentration. (FDA-approved label, retrieved 2026-09-15. Tell your clinician about every medication and supplement you take.)
Theophylline Anhydrous is $0 on the covered list
Members pay $0 for covered generics at participating pharmacies nationwide or by mail order — plus unlimited virtual primary care, urgent care and dermatology visits. No insurance needed.
Solo $49/mo · Family $119/mo for up to 4 people · Family+ $149/mo for up to 8
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