Do NOT use Quibron-T if:

you are allergic to any ingredient in Quibron-T, 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

Contact your doctor or health care provider right away if any of these apply to you.

Some medical conditions may interact with Quibron-T. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:

if you are pregnant, planning to become pregnant, or are breast-feeding

if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement

if you have allergies to medicines, foods, or other substances

if you have a history of heart problems (eg, congestive heart failure, cor pulmonale), an irregular heartbeat, liver problems (eg, cirrhosis,hepatitis), viral infection, thyroid problems, increased acid levels in the body, brain or nerve problems, or seizures (eg, epilepsy)

if you are in shock or have a fever, an ulcer, a severe infection, cystic fibrosis, or fluid in the lungs (pulmonary edema)

if you smoke, are stopping or starting smoking, or are exposed to the smoke from cigarettes or marijuana

if you are in the last 3 months of pregnancy

Important safety information:

Drinking alcohol may increase the risk of side effects of Quibron-T. Talk to your doctor before drinking alcohol while you are taking Quibron-T.

Tell your doctor or dentist that you take Quibron-T before you receive any medical or dental care, emergency care, or surgery.

Do not take more than the recommended dose or use more often than prescribed without checking with your doctor. If your symptoms become worse, contact your doctor.

Carry an ID card at all times that says you take Quibron-T.

Avoid large amounts of food or drink that have caffeine (eg, coffee, tea, cocoa, cola, chocolate).

Notify your doctor if you develop a new illness, especially if it is accompanied by fever; if a chronic illness becomes worse; or if you start or stop smoking cigarettes or marijuana.

Tell your doctor if another doctor prescribes a new medicine or tells you to stop using a medicine that you have already been taking. Tell your doctor if you start or stop any medicine, either prescription or over the counter.

Quibron-T will not stop an asthma attack once one has started. Be sure to always carry appropriate rescue medicine (eg, bronchodilator inhaler) with you in case of an asthma attack.

If you have more than one doctor, be sure to tell each of your doctors that you are taking Quibron-T.

Diabetes patients - Quibron-T may affect your blood sugar. Check blood sugar levels closely. Ask your doctor before you change the dose of your diabetes medicine.

Quibron-T may interfere with certain lab tests. Be sure your doctor and lab personnel know you are taking Quibron-T.

Lab tests, including blood theophylline levels, may be performed while you use Quibron-T. These tests may be used to monitor your condition or check for side effects. Be sure to keep all doctor and lab appointments.

Use Quibron-T with caution in the ELDERLY; they may be more sensitive to its effects.

Caution is advised when using Quibron-T in CHILDREN, especially children younger than 1 year old; they may be more sensitive to its effects. Children may be more likely to experience mild, temporary behavior changes.

PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor.

You will need to discuss the benefits and risks of using Quibron-T while you are pregnant. Quibron-T is found in breast milk. If you are or will be breast-feeding while you use Quibron-T, check with your doctor. Discuss any possible risks to your baby.

All medicines may cause side effects, but many people have no, or minor, side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:

Irritability; mild, temporary caffeine-like effects (eg, headache, nausea, diarrhea, trouble sleeping); mild, temporary changes in behavior; restlessness; temporary increased urination.

Seek medical attention right away if any of these SEVERE side effects occur:

Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); confusion; dizziness; fast breathing; fast or irregular heartbeat; heart rhythm problems; seizures; severe or persistent nausea, diarrhea, or headache; sleeplessness; tremors; vomiting.

This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects.