theophylline (generic name)

T-Phyl (brand name)

It helps open up the airways in your lungs to make it easier to breathe
(the OFF i lin)
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What is this medicine?

THEOPHYLLINE (the OFF i lin) is a bronchodilator. It helps open up the airways in your lungs to make it easier to breathe. This medicine is used to treat the symptoms of asthma, bronchitis, and emphysema.

What should I tell my health care provider before I take this medicine?

They need to know if you have any of these conditions:
  • heart disease
  • if you smoke
  • irregular heartbeat
  • liver disease
  • seizures
  • stomach problems like ulcers
  • thyroid disease
  • an unusual or allergic reaction to theophylline, aminophylline, caffeine, theobromine, other medicines, foods, dyes, or preservatives
  • pregnant or trying to get pregnant
  • breast-feeding

How should I use this medicine?

Take this medicine by mouth with a glass of water. Follow the directions on the prescription label. Take this medicine on an empty stomach, at least 1 hour before eating. Do not crush or chew. Take your doses at the same time each day. Do not take your medicine more often than directed. Do not stop taking except on your doctor's advice.

Talk to your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for selected conditions, precautions do apply.

What if I miss a dose?

If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

What may interact with this medicine?

  • adenosine
  • allopurinol
  • aminoglutethimide
  • caffeine
  • cimetidine
  • disulfiram
  • ephedrine
  • fluvoxamine
  • interferon
  • isoproterenol
  • lithium
  • medicines for anxiety or sleep
  • medicines for colds and breathing difficulties
  • methotrexate
  • pentoxifylline
  • some antibiotics or anti infectives
  • some medicines for irregular heart rhythms
  • some medicines for treating seizures
  • some medicines used during surgery
  • sulfinpyrazone
  • tacrine

What should I watch for while using this medicine?

Visit your doctor or health care professional for regular checks on your progress. Your doctor or health care professional may schedule regular blood tests, especially at first. Tell your doctor if your symptoms do not improve or if they get worse.

There are many different brands of this medicine. Do not change your brand without checking with your health care professional. Different brands of this medicine may act differently in your body.

Tell all of your doctors that you are taking this medicine. Talk to your doctor before you start or stop ANY over-the-counter or prescription medicines. Also talk to your health care professional about foods that affect this medicine, like chocolate, coffee, teas and charcoal-broiled foods. If you smoke tobacco or marijuana you may affect the level of this medicine in your body. Alcohol may interfere with the effect of this medicine. Avoid alcoholic drinks.

What side effects may I notice from receiving this medicine?

Side effects that you should report to your doctor or health care professional as soon as possible:
  • allergic reactions like skin rash, itching or hives, swelling of the face, lips, or tongue
  • fast or irregular breathing or heartbeat
  • feeling faint or lightheaded, falls
  • fever, infection
  • nausea, vomiting
  • seizures

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

  • anxiety, irritable, restless
  • diarrhea
  • headache
  • increased need to pass urine
  • tremors
  • trouble sleeping

Where should I keep my medicine?

Keep out of the reach of children.

Store at room temperature below 25 degrees C (77 degrees F). Keep container tightly closed. Protect from light and moisture. Throw away any unused medicine after the expiration date.

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Last Updated: September 03, 2009
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