Theo Dur (Theophylline SR)

Theo Dur

(Brand Option)

Prescription RequiredPrescription Required

This brand medication is not available at the moment.

Theophylline SR

(Generic Alternative)

Prescription RequiredPrescription Required
FormulationFormulation: 12H ER Scored Tablet
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$41.00 ($0.41 per tablet)

$43.00 ($0.43 per tablet)

$45.00 ($0.45 per tablet)

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Theo Dur is indicated for the treatment of lung diseases such as asthma and COPD (bronchitis, emphysema). It is used regularly to prevent wheezing and shortness of breath. This medication belongs to a class of drugs known as xanthines and works by relaxing the muscles around the airways so that they open up, allowing for easier breathing.


  • Take Theo Dur by mouth as directed by your healthcare provider, usually once or twice daily. Swallow the whole or split tablet without crushing or chewing.
  • For once daily regimen, take this medication every morning at the same time each day. If prescribed to take twice daily, you may take your second dose 10 to 12 hours after the morning dose and before the evening meal, unless your healthcare provider tells you otherwise.
  • The dosage is based on your medical condition, response to treatment, age, weight, lab tests (theophylline blood levels), and other medications you may be taking. Inform your healthcare provider about all the products you use, including prescription drugs, nonprescription drugs, and herbal products.
  • To reduce your risk of side effects, your healthcare provider may direct you to start this medication at a low dose and gradually increase your dose. Follow their instructions carefully.
  • Take this medication regularly to get the most benefit from it. To help you remember, take it at the same time(s) each day.
  • Keep taking this medication even if you feel well. 
  • Get medical help right away if your asthma symptoms worsen or if you are using your quick-relief inhaler more than usual or more often than prescribed.


  • Do not crush or chew the tablets. Doing so can release all of the drug at once, increasing the risk of side effects. Also, do not split the tablets unless they have a score line and your healthcare provider tells you to do so. 
  • Do not increase your dose, take this drug more often, or stop taking it without first consulting your healthcare provider.

Common Adverse Effects:

  • Nausea
  • Vomiting
  • Headache
  • Insomnia
  • Upset stomach
  • Stomach pain
  • Diarrhea
  • Restlessness
  • Difficulty falling asleep or staying asleep
  • Irritability

Severe Effects:

  • Seizures in patients with underlying neurological disease or elderly patients with serum theophylline levels under 20 mcg/mL

Long-term Effects:

  • Caffeine-like adverse effects
  • Decreased protein binding causing higher unbound (pharmacologically active) theophylline levels

This is not an exhaustive list of side effects. If you experience any symptoms or side effects, consult your healthcare provider for medical advice. 

A healthcare provider should be consulted before taking Theo Dur and any drug, changing any diet, or commencing or discontinuing any course of treatment.

Elderly patients may be more sensitive to the effects of theophylline than younger adults and are more likely to have kidney, liver, heart, or lung problems, which may require caution and an adjustment in the dose.

Studies in women suggest that this medication poses minimal risk to the infant when used during breastfeeding. Caution is advised for pediatric and geriatric patients, and appropriate studies have not demonstrated pediatric-specific problems that would limit the usefulness of Theo Dur in children.

Overdose can occur if accidentally taking too much at one time or if daily doses are too high. If you think you or someone else may have overdosed, immediate medical assistance should be sought.

Adhere to these warnings and precautions and consult a healthcare provider for personalized advice related to the use of Theo Dur.

Brand Name:

Theo Dur

Generic name:

Theophylline SR

Other Names:

Theo LA, Theo La

Strength(s): 100mg, 200mg, 300mg
Quantities Available: 100

12H ER Scored Tablet

Important Information
The information above for Theo Dur (Theophylline SR) was provided to by third parties. In no way should this information substitute for the advice of a physician. Consult a doctor or qualified health care professional if you have any medical concerns. widget logo
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