Theophylline belongs to a class of drugs known as xanthines that works in the airways by relaxing muscles, opening breathing passages, and decreasing the lungs’ response to irritants.

This medication is used to prevent and treat symptoms and blockage of airway due to asthma or other lung diseases (eg, emphysema, bronchitis). It may also be used for other conditions as determined by your doctor.

Do not use Theophylline if:

  • You are allergic to any ingredient in Theophylline, similar medicines (eg, Aminophylline), or Xanthines (eg, caffeine, chocolate)
  • You are using large amounts of other products that contain Xanthine (such as chocolate or caffeinated drinks)
  • You are taking Dipyridamole intravenously (IV), Febuxostat, Halothane, or St. John’s wort

If any of these apply to you, contact your doctor or health care provider right away.

Side effects of this drug include:

  • Upset Stomach
  • Stomach Pain
  • Diarrhea
  • Headache
  • Restlessness
  • Insomnia
  • Irritability

If any of these apply to you, contact your doctor or health care provider right away:

  • Vomiting
  • Increased Or Rapid Heart Rate
  • Irregular Heartbeat
  • Seizures
  • Skin Rash

Tell your doctor promptly if any of these effects persist or worsen.


Before using Theophylline, tell your doctor or pharmacist if you are allergic to it; or to other Xanthine drugs (such as Aminophylline, Oxtriphylline, Caffeine); or if you have any other allergies. This product may contain inactive ingredients, which can trigger allergic reactions or other problems.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

  • Stomach/Intestinal Ulcer
  • Seizures
  • Thyroid Disease
  • Heart Problems (Such As Heart Failure, Irregular Heartbeat)
  • Liver Disease
  • High Blood Pressure.



Drug interactions may interfere with how your medication works. Tell your doctor about all your medications and any you start or stop using during treatment with Theophylline.

Products that may interact with this drug are:

  • Riociguat
  • Cimetidine
  • Disulfiram
  • Fluvoxamine
  • Interferon
  • Mexiletine
  • Propranolol
  • Rifampin
  • Drugs Used To Treat Seizures (Such As Carbamazepine, Phenytoin)
  • John’s Wort
  • Ticlopidine

Call emergency hotline if someone has overdosed and has serious symptoms such as passing out or trouble breathing. Symptoms of overdose may include:

  • Nausea/Vomiting That Doesn’t Stop
  • Seizures
  • Muscle Cramps
  • Fast/Irregular Heartbeat
  • Mental/Mood Changes (Such As Agitation, Confusion)
  • Vomit That Looks Like Coffee Grounds


Available brands:

  • Nuelin/Nuelin SR 125/Nuelin SR 250

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