Theophylline Anhydrous

Nausea/vomiting, stomach/abdominal pain, headache, trouble sleeping, diarrhea, irritability, restlessness, nervousness, shaking, or increased urination may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including: nausea/vomiting that doesn't stop, fast/slow/irregular heartbeat, muscle cramps, fainting, confusion, dizziness.

Get medical help right away if you have any very serious side effects, including: seizures.

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including: rash, itching/swelling (especially of the face/tongue/throat), severe dizziness, trouble breathing.

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US -

Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

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 cause allergic reactions or other problems. Talk to your pharmacist for more details.

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.

If you get sick or have a fever while taking this medication, tell your doctor right away. The dose of your medicine may need to be adjusted.

This product may contain sugar and/or alcohol. Caution is advised if you have diabetes, liver disease, or any other condition that requires you to limit/avoid these substances in your diet. Ask your doctor or pharmacist about using this product safely.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Older adults may be more sensitive to the side effects of this drug, especially fast/irregular heartbeat, or trouble sleeping. Careful monitoring of side effects and drug blood levels is recommended.

Children may be more sensitive to the side effects of this drug. Careful monitoring of side effects and drug blood levels is recommended.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor. Changes in your body during the last 3 months of pregnancy may affect the amount of this drug in your blood. Your doctor should carefully monitor the amount of drug in your blood, as well as any side effects, so that your dose may be changed if needed.

This drug passes into breast milk and may have undesirable effects on a nursing infant. Consult your doctor before breast-feeding.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

A product that may interact with this drug is: riociguat.

Other medications can affect the removal of theophylline from your body, which may affect how theophylline works. Examples include cimetidine, disulfiram, fluvoxamine, interferon, mexiletine, propranolol, rifampin, drugs used to treat seizures (such as carbamazepine, phenytoin), St. John's wort, ticlopidine, viloxazine, among others.

Cigarette/marijuana (cannabis) smoking decreases blood levels of this medication. Tell your doctor if you smoke or if you have recently stopped smoking.

Caffeine and alcohol can increase the side effects of this medication. Avoid drinking large amounts of beverages containing alcohol or caffeine (such as coffee, tea, colas), eating large amounts of chocolate, or taking nonprescription products that contain caffeine.

Theophylline is very similar to aminophylline and oxtriphylline. Do not use medications containing aminophylline or oxtriphylline while using theophylline.

This medication may interfere with certain lab tests (such as blood sugar, cholesterol, uric acid, dipyridamole-thallium imaging tests), possibly causing false test results. Make sure lab personnel and all your doctors know you use this drug.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call their local poison control center at 1-800-222-1222. Canada residents can call a provincial poison control center. 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.

Do not share this medication with others.

Lab and/or medical tests (such as theophylline blood levels) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.

If you miss a dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

Your condition can cause complications in a medical emergency. For information about enrolling in MedicAlert, call 1-888-633-4298 (US) or 1-800-668-1507 (Canada).