Terbutaline: Uses, Mechanism, Side Effects, Dosage Information

Terbutaline is an agonist of beta-adrenergic receptors used for the prevention and resolution of bronchospasm in patients 12 years of age and older with asthma and reversible bronchospasm associated with bronchitis and emphysema.

Terbutaline was approved by The Food and Drug Administration (FDA)  in 1974.

Mechanism of action

The pharmacological effects of terbutaline are at least partially due to stimulation by beta-adrenergic receptor intracellular adenyl cyclase, the enzyme that catalyzes the conversion of adenosine triphosphate (ATP) into ciclosporin-3 ‘, 5’ adenosine monophosphate (c-AMP). Elevated c-AMP levels are associated with bronchial smooth muscle relaxation and the inhibition of mediator release from the immediate hypersensitivity of cells, particularly mast cells.

Side effects

The most common side effects that can occur with terbutaline are:

• Nausea,
• Vomiting,
• Weakness,
• Nervousness
• Tremor
• A headache
• Fast heartbeat
• Flushed feeling,
• Sweating,
• Pain at the injection site,
• Anxiety,
• Shortness of breath,
• Chest discomfort,
• Shortness of breath,
• Chest discomfort,
• Dizziness,
• Drowsiness,
• Palpitations,

While Serious side effects  may include :

• Hallucinations

Interaction With other drugs

When taken with terbutaline, certain drugs can worsen the side effects ofthis drug. Examples of these drugs include:

• Amitriptyline
• Doxepin
• Phenelzine
• Selegiline
• Metoprolol
• Labetalol
• Furosemide
• Hydrochlorothiazide

Terbutaline during pregnancy

It should not be used to stop or prevent premature labor in pregnant women, especially in women who are not hospitalized. Terbutaline caused severe side effects, including death, in pregnant women who took the drug for this purpose. Terbutaline also caused serious side effects in newborns whose mothers took the drug to stop or prevent childbirth.

Precautions

Consult your doctor before using Terbutaline if you have

• Thyroid problem
• Diabetes
• Heart disease
• High blood pressure
• Glaucoma
• Low levels of potassium in your blood.
• had an allergic reaction to a medicine.

Dosage for terbutaline

• The recommended dose in adults for the treatment of bronchospasm for asthma, emphysema or bronchitis is 2.5 to 5 mg, 3-4 times daily, and about 6 hours apart while awake. The maximum dose is 15 mg/day.
• The recommended subcutaneous dose (under the skin) is 0.25 mg every 15-30 minutes for two doses. The maximum dose is 0.5 mg within 4 hours.
• The recommended dose for the inhaler is 2 puffs every 4 to 6 hours.
• The premature labor dose is initially 2.5 to 10 mcg/min with intravenous infusion, then the dose increases every 10 to 20 minutes. The typical effective dose is 17.5 to 30 mcg/min. The treatment should not exceed 72 hours.

Overdose

Symptoms of a Terbutaline overdose may include Chest pain, Fainting or dizziness, Vomiting, Nervousness, Excessive tiredness or weakness, Dry mouth,Pounding, fast, or irregular heartbeat, Headache, Uncontrollable shaking of a part of the body, Difficulty falling asleep or staying asleep, Seizures. If these symptom occur contact your GP.

Missed Dose

If you miss a dose of this drug take it as soon as you remember. But if it’s almost time for your next dose, skip the missed dose and continue with your regular medication schedule.

More at DrugsBank