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Generic Name: terbutaline (ter-BUE-ta-leen)
Brand Name: Generic only. No brands available.

Brethine should not be used to treat or prevent premature labor. Serious and sometimes fatal side effects, including fast or irregular heartbeat, high blood sugar, low blood potassium levels, fluid in the lungs, and heart attack, have been reported after the use of Brethine in pregnant women. Brethine may also cause fast heartbeat or low blood sugar in the fetus or newborn if given to a pregnant woman.

Brethine are used for:

Treating or preventing symptoms caused by spasms or contractions of the muscles around the bronchioles (air tubes) associated with asthma, bronchitis, and emphysema. It may also be used for other conditions as determined by your doctor.

Brethine are a bronchodilator. It works by dilating (opening) the bronchioles of the lungs by relaxing the muscles around them. This allows for easier airflow into and out of the lungs.

Do NOT use Brethine if:

  • you are allergic to any ingredient in Brethine or to a sympathomimetic amine (eg, epinephrine, albuterol)
  • you need to treat or prevent premature labor

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

Before using Brethine:

Some medical conditions may interact with Brethine. 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 heart disease, an irregular heartbeat, high blood pressure, an overactive thyroid, diabetes, a history of seizures, or an adrenal gland tumor
  • if you have taken a monoamine oxidase inhibitor (MAOI) (eg, phenelzine) or a tricyclic antidepressant (eg, amitriptyline) within the past 14 days

Some MEDICINES MAY INTERACT with Brethine. Tell your health care provider if you are taking any other medicines, especially any of the following:

  • Catechol-O-methyltransferase (COMT) inhibitors (eg, entacapone), droxidopa, MAOIs (eg, phenelzine), or tricyclic antidepressants (eg, amitriptyline) because the risk of side effects, such as life-threatening irregular heartbeat, may be increased
  • Diuretics (eg, furosemide) or other sympathomimetic medicines (eg, pseudoephedrine, albuterol) because the risk of their side effects may be increased by Brethine
  • Beta-blockers (eg, propranolol) because they may decrease Brethine's effectiveness
  • Insulin because its effectiveness may be decreased by Brethine

This may not be a complete list of all interactions that may occur. Ask your health care provider if Brethine may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.

How to use Brethine:

Use Brethine as directed by your doctor. Check the label on the medicine for exact dosing instructions.

  • Take Brethine by mouth with or without food.
  • If you miss a dose of Brethine, take it as soon as possible. If it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not take 2 doses at once.

Ask your health care provider any questions you may have about how to use Brethine.

Important safety information:

  • Brethine may cause drowsiness or dizziness. These effects may be worse if you take it with alcohol or certain medicines. Use Brethine with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
  • Do NOT take more than the recommended dose or take more often than prescribed without checking with your doctor.
  • If your breathing problems do not improve, if they get worse, or if you need to use Brethine more often than usual, contact your doctor immediately.
  • Diabetes patients - Brethine may affect your blood sugar. Check blood sugar levels closely. Ask your doctor before you change the dose of your diabetes medicine.
  • Check with your doctor or pharmacist before taking Brethine if you have taken an MAOI (eg, phenelzine) or a tricyclic antidepressant (eg, amitriptyline) within the last 2 weeks. The effects of these medicines are long lasting and may still interact with Brethine.
  • Brethine should not be used in CHILDREN younger than 12 years; safety and effectiveness in these children have not been confirmed.
  • PREGNANCY and BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of taking Brethine while you are pregnant. Do not use Brethine to treat or prevent premature labor. It is not known if this medicine is found in breast milk. If you are or will be breast-feeding while you take Brethine, check with your doctor. Discuss any possible risks to your baby.

Possible side effects of Brethine:

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:

Difficulty sleeping; dizziness; drowsiness; headache; nausea; nervousness.

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); burning, numbness, or tingling; chest pain; fast or irregular heartbeat; hallucinations; increased difficulty breathing; muscle pain, weakness, or cramping; pounding in the chest; seizures; severe or persistent headache or dizziness; tremor; wheezing.

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. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.

If OVERDOSE is suspected:

Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include anxiety; chest pain; drowsiness; dry mouth; fainting; fast or irregular heartbeat; gasping; muscle cramps; nervousness; seizures; severe or persistent dizziness, headache, or nausea; sweating; tremor; unconsciousness; vomiting.

Proper storage of Brethine:

Store Brethine at room temperature between 59 and 86 degrees F (15 and 30 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. Keep Brethine out of the reach of children and away from pets.

General information:

  • If you have any questions about Brethine, please talk with your doctor, pharmacist, or other health care provider.
  • Brethine are to be used only by the patient for whom it is prescribed. Do not share it with other people.
  • If your symptoms do not improve or if they become worse, check with your doctor.
  • Check with your pharmacist about how to dispose of unused medicine.

This information should not be used to decide whether or not to take Brethine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about Brethine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Brethine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using Brethine.

Issue Date: June 3, 2015

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.