5-(1-Hydroxy-2-tert-butylamino-ethyl)benzene-1,3-diol

Absorption

A 0.5 mg subcutaneous dose of terbutaline reaches a mean Cmax of 9.6 ± ng/mL, with a median Tmax of 0.5 hours, and a mean AUC of 29.4 ± 14.2 h*ng/mL. A 5 mg oral terbutaline tablet reaches a mean Cmax of 8.3 ± 3.9 ng/mL with a median Tmax of 2 hours, and a mean AUC of 54.6 ± 26.8 h*ng/mL. A 5 mg oral terbutaline solution reaches a mean Cmax of 8.6 ± 3.6 ng/mL, with a median Tmax of 1.5 hours, and a mean AUC of 53.1 ± 23.5 h*ng/mL.
Oral terbutaline has an oral bioavailability of 14-15%.

Toxicity

Patients experiencing an overdose may present with abdominal pain, agitation, palpitations, seizures, angina, hypertension, hypotension, tachycardia, arrhythmias, nervousness, headache, tremor, dry mouth, nausea, dizziness, fatigue, malaise, insomnia. Discontinue treatment with terbutaline and initiate symptomatic and supportive therapy.

Description

Terbutaline is a synthetic congener of adrenaline that acts at the β2-receptor causing bronchodilation and tocolytic effects. It was the first β2-selective adrenoreceptor agonist in general clinical use. In 2011, the Food and Drug Administration (FDA) placed a black-boxed warning on terbutaline stating that terbutaline injections should not be given to pregnant women nor should be used to prevent preterm labor or for long-term (greater than 48–72 h) treatment of preterm labor. Oral terbutaline should not be used at all due to its potential for cardiac toxicity and death. Terbutaline is on the World Anti- Doping Agency’s list of prohibited drugs for Olympic athletes (except when a Therapeutic Use Exemption has been granted in advance and when used by inhalation).

The Uses of 5-(1-Hydroxy-2-tert-butylamino-ethyl)benzene-1,3-diol

Terbutaline is used for preventing and relieving bronchospasms in bronchial asthma, chronic bronchitis, pulmonary emphysema, and other broncho-pulmonary diseases.

Indications

Terbutaline is indicated for prevention and reversal of bronchospasm in patients at least 12 years old, with asthma and reversible bronchospasm associated with bronchitis and emphysema.

Background

Terbutaline was first synthesized in 1966 and described in the literature in the late 1960s and early 1970s. It is a selective beta-2 adrenergic agonist used as a bronchodilator in asthmatic patients.
Terbutaline was granted FDA approval on 25 March 1974.

Pharmacokinetics

Terbutaline is a beta-2 adrenergic receptor agonist indicated to treat reversibly bronchospasm in asthmatic patients with bronchitis and emphysema. It has a short duration as the inhaled form is taken up to three times daily, and the therapeutic window is wide.

Metabolism

Terbutaline is sulphated or glucuronidated prior to elimination.