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Generic Name: terbutaline (oral) (ter BYOO ta leen)
Brand Name: Brethine

Medically reviewed by on Dec 30, 2019 – Written by Cerner Multum

What is Brethine?

Brethine is a bronchodilator. It works by relaxing muscles in the airways to improve breathing.

Brethine is used to treat or prevent bronchospasm (wheezing, chest tightness, trouble breathing) in people with lung conditions such as asthma, bronchitis, or emphysema.

Brethine may also be used for purposes not listed in this medication guide.

Important Information

Brethine is not safe to use in a pregnant woman to prevent premature labor.

Before taking this medicine

You should not use Brethine if you are allergic to it.

To make sure Brethine is safe for you, tell your doctor if you have:

FDA pregnancy category B. Brethine is not expected to harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

Brethine is not safe to use in a pregnant woman to prevent premature labor.

It is not known whether terbutaline passes into breast milk or if it could harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

Brethine should not be given to a child younger than 12 years old.

How should I take Brethine?

Follow all directions on your prescription label. Do not take Brethine in larger or smaller amounts or for longer than recommended.

Use Brethine regularly to get the most benefit. Get your prescription refilled before you run out of medicine completely.

Your doctor may prescribe other medications to treat your condition. Use all medications as directed. Do not change your doses or medication schedule without your doctor's advice.

To make sure this medication is not causing harmful effects on your lungs, you may need to have chest X rays or other frequent lung function tests.

Seek medical attention if you think your asthma medications are not working as well. An increased need for medication could be an early sign of a serious asthma attack.

Store at room temperature away from moisture, heat, and light.

What happens if I miss a dose?

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Brethine?

Avoid situations that may worsen your respiratory condition such as exercising in cold, dry air; smoking; breathing in dust; and exposure to allergens such as pet fur.

Brethine side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • chest pain, fast heart rate;

  • pounding heartbeats or fluttering in your chest;

  • a light-headed feeling, like you might pass out;

  • tremors; or

  • worsening or no improvement in your symptoms.

Common side effects may include:

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

What other drugs will affect Brethine?

You should not take Brethine if you have used an MAO inhibitor in the past 14 days. A dangerous drug interaction could occur. MAO inhibitors include isocarboxazid, linezolid, methylene blue injection, phenelzine, rasagiline, selegiline, tranylcypromine, and others.

Tell your doctor about all medicines you use, and those you start or stop using during your treatment with Brethine, especially:

This list is not complete. Other drugs may interact with terbutaline, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Further information

  • Your pharmacist can provide information about Brethine written for health professionals that you may read.

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.

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