Terbutaline Pharmacology


About Terbutaline
A ?2-adrenergic agonist,a fast-acting bronchodilator, Tocolytic,Anti asthma.
Mechanism of Action of Terbutaline
Terbutaline is a ?2 receptor agonist. Terbutaline directly relaxes the airway smooth muscles and produces bronchodilation. Stimulation of ?2 receptors activates Gs adenylyl-cyclase -cyclic AMP path way and produces reduction in smooth muscle tone. ?2 receptor agonists also increases the conductance of large Ca2+sensitive K+ channels in airway smooth muscles and leads to membrane hyperpolarisation and relaxation of smooth muscles.
Tocolytic action: In premature labour Terbutaline relaxes uterine smooth muscles and inhibits uterine contractions.

Pharmacokinets of Terbutaline
Absorption: It is partially absorbed (about 33- 50%) after oral administration
Distribution: It is widely distributed in the body.
Metabolism: It is partially metabolised in the liver to inactive compounds.
Excretion: Drug and its metabolites are excreted mainly in urine.

Onset of Action for Terbutaline
30 minutes (oral), 15 minutes (subcutaneous), 5-30 minutes (inhalation)
Duration of Action for Terbutaline
4- 8 hours (oral), 1.5-4 hours (subcutaneous), 3- 6 hours (inhalation).
Half Life of Terbutaline
Side Effects of Terbutaline
1. Drowsiness
2. Headache
3. Dizziness
4. Nervousness
5. Tremor
6. Weakness
7. Palpitations
8. Tachycardia
9. Arrhythmia
10. Vomiting
11. Nausea
12. Heartburn
13. Diaphoresis
14. Dry and irritated nose (inhalation)
15. Hypokalaemia (high dose)
Contra-indications of Terbutaline
1. Hypersensitivity to Terbutaline and other sympathomimetic amines.
Special Precautions while taking Terbutaline
1. Myocardial insufficiency
2. Arrhythmia
3. Hypertension
4. Hyperthyroidism
5. Epilepsy
6. Diabetes
Pregnancy Related Information
Use with caution.
Old Age Related Information
Use with caution.
Breast Feeding Related Information
Use with caution.
Children Related Information
Use with caution
CHILDREN Below 12 years : contraindicated
NEONATES: contraindicated
Indications for Terbutaline
1. Obstructive airway diseases
2. Acute Bronchospasm
3. Status asthmaticus
4. Premature labour
Interactions for Terbutaline
Other Sympathomimetic bronchodilators or epinephrine: Combined effect on the cardiovascular system may be deleterious to the patient.
MAOIs and TCAs: Effect of terbutaline on vascular system may be potentiated.
Beta-adrenergic blocking agents: Block the pulmonary effect of terbutaline and may produce severe asthmatic attacks in asthmatic patients.
Beclomethasone, Theophylline: Synergy when used with these agents.
Food: Reduces bioavailability of terbutaline.
Typical Dosage for Terbutaline
Oral: Initial dose: 7.5 mg / day in 3 divided doses, if needed dose can be increased to 15mg /day in 3 divided doses.
Subcutaneous /Intramuscular/slow IV infusion: 250 - 500mcg 3 - 4 times daily
Aerosol inhalation: 250 - 500mcg every 6 - 8 hours
Nebulised solution inhalation: 5 - 10 mg every 6 - 12 hours.
Oral: Initial dose: 2.5 mg in 2-3 times daily
Subcutaneous /Intramuscular/slow IV infusion: 10mcg /kg body weight dose can be increased to 300 mcg / day
Aerosol inhalation: 250 - 500mcg every 6 - 8 hours
Nebulised solution inhalation: 2 - 5 mg every 6 - 12 hours.
Premature labor (IV): Initial dose: 10mcg/minute and dose can be repeated until effective therapeutic response is obtained. Maximum dose: 80mcg/minute. Maintenance dose (IV dosage): Minimum effective dose for 4 hours.

Schedule of Terbutaline
Storage Requirements for Terbutaline
Store at 15 - 30 degree C. Protect from heat and light.
Effects of Missed Dosage of Terbutaline
Take the missed dose as soon as noticed and if it is the time for next dose then skip the missed dose. Continue the regular schedule. Do not double the dose.
Effects of Overdose of Terbutaline
Give supportive measures and symptomatic treatment. Drug can be removed from the body by gastric lavage or by inducing emesis. Absorption of drug can be reduced by administration of activated charcoal.

Home Delivery for Terbutaline in Your City

Medicine India is just a publishing medium for medicine related information and does not provide services or sales of medicines including terbutaline.

However, we do publish a comprehensive directory of Pharmacies, Chemists and Druggists in cities all over India. You can use this directory to find the medicine stores in your city (or area) that provide home delivery services for terbutaline and other medicines and health products. Home delivery services for terbutaline may be free or they may cost you depending on the pharmacy and the minimum order requirements. It would be best to get this clarified while placing the order.

Please be aware that you should take terbutaline only if a doctor has recommended or prescribed it. Some or all pharmacies who provide a home delivery service for medicines might insist on a prescription for terbutaline before they complete the sale. You can get this information while placing the order for terbutaline with the pharmacy.

Terbutaline is a generic medicine name and there are several brands available for it. Some of the brands for terbutaline might be better known than terbutaline itself. If the pharmacy that's willing to deliver medicines to your home doesn't have terbutaline in stock, you can ask for one of the branded alternatives for terbutaline.