Overview of Terbutaline Sulfate for Dogs and Cats

 Terbutaline Sulfate, also known as Brethine® or Bricanyl®, is used to assist breathing in specific airway diseases through its bronchodilation effects in dogs and cats. On occasion, Terbutaline is also used to treat some slow heart arrhythmias.  It is available as both an oral pill and as a solution for injection. 

Terbutaline is a drug that stimulates type 2 beta-adrenergic receptors. Beta-receptors are cell membrane targets that modify organ activity when stimulated by norepinephrine, epinephrine or related drugs.

Stimulation of beta-2 receptors in smooth muscle causes the muscle to relax. This muscle relaxation results in dilation of the airways and blood vessels and can slow down or halt premature uterine contractions and labor.

Terbutaline predominately stimulates beta-2 receptors in the airways and uterus, causing these muscles to relax.

The major use of terbutaline in pets is in the treatment of bronchial disease such as asthma and bronchitis.

Terbutaline is a prescription drug and can only be obtained from a veterinarian or by prescription from a veterinarian.

This drug is not approved for use in animals by the Food and Drug Administration but it is prescribed legally by veterinarians as an extra-label drug.

Brand Names and Other Names of Terbutaline Sulfate

This drug is registered for use in humans only.

Human formulations: Brethine® (Novartis), Bricanyl® (Hoechst Marion Roussel) and various generic preparations

Veterinary formulations: None

Uses of Terbutaline for Dogs and Cats

The primary use of terbutaline in animals is to assist breathing in specific airway diseases through its bronchodilation effects.

Terbutaline has been used as an adjunct treatment for bronchitis, collapsing trachea, asthma and mild heart failure.

Terbutaline is also used to treat some cardiac bradyarrhythmias.

Little information is available on the effects of halting premature labor in animals and this is not a routine use of terbutaline in animals.

Precautions and Side Effects

While generally safe and effective when prescribed by a veterinarian, terbutaline can cause side effects in some animals.

Terbutaline should not be used in animals with known hypersensitivity or allergy to the drug.

Terbutaline should be used cautiously in animals with diabetes, high blood pressure, overactive thyroid gland (hyperthyroidism), animals taking thyroid supplement (L-thyroxine) or those with a seizure disorder or epilepsy.

Terbutaline should be avoided if any heart rhythm abnormalities are present.

Terbuatine may interact with other medications. Consult with your veterinarian to determine if other drugs your pet is receiving could interact with terbutaline. Such drugs include certain antidepressants and anesthetics.

Adverse effects are generally related to the dose of terbutaline and can include tremors, increased heart rate or nervousness.

How Terbutaline Is Supplied

Terbutaline is available in 2.5 mg and 5 mg tablets.

It is also available in 1 mg/ml injectable form as well as an inhaler form.

Dosing Information of Terbutaline Sulfate for Dogs and Cats

Medication should never be administered without first consulting your veterinarian.

For dogs and cats, the injectable form of terbutaline is dosed at 0.005 mg per pound (0.01 mg/kg) every 4 to 6 hours.

For dogs, the tablet form of terbutaline is dosed at 1.25 to 5 mg per dog three times per day.

For cats, the tablet form of terbutaline is dosed at 0.05 to 0.1 mg per pound (0.1 to 0.2 mg/kg) twice daily.

The duration of administration depends on the condition being treated, response to the medication and the development of any adverse effects. Be certain to complete the prescription unless specifically directed by your veterinarian. Even if your pet feels better, the entire treatment plan should be completed to prevent relapse or prevent the development of resistance.