Terbutaline

Overview

Terbutaline, sold under the brand names Bricanyl and Marex among others, is a β₂ adrenergic receptor agonist, used as a "reliever" inhaler in the management of asthma symptoms and as a tocolytic (anti-contraction medication) to delay preterm labor for up to 48 hours. This time can then be used to administer steroid injections to the mother which help fetal lung maturity and reduce complications of prematurity. It should not be used to prevent preterm labor or delay labor more than 48–72 hours. In February 2011, the Food and Drug Administration began requiring a black box warning on the drug's label. Pregnant women should not be given injections of the drug terbutaline for the prevention of preterm labor or for long-term (beyond 48–72 hours) management of preterm labor, and should not be given oral terbutaline for any type of prevention or treatment of preterm labor "due to the potential for serious maternal heart problems and death."[1][2][3] WP

It was patented in 1966 and came into medical use in 1970. It is on the World Health Organization's List of Essential Medicines.[4][5] WP

Uses, dosage and effects

Medical uses

Terbutaline is used as a fast-acting bronchodilator (often used as a short-term asthma treatment) and as a tocolytic to delay premature labor.[6] WP

As an asthma treatment, the inhaled form of terbutaline starts working within 15 minutes and can last up to 6 hours. It is also sold as an injectable solution, an oral tablet, and as a syrup (in combination with guaifenesin). WP

Terbutaline is a pregnancy category C medication and is prescribed to stop contractions. After successful intravenous tocolysis, little evidence exists that oral terbutaline is effective. Terbutaline as a treatment for premature labor is an off-label use not approved by the US FDA, who have warned that oral terbutaline is not effective and can cause severe heart problems or death, and while injectable terbutaline can be used for premature labor in emergency situations in a hospital setting, it should only be used for short periods of time.[7][8] WP

Risks and side effects

Side effects

• Adult – tachycardia, anxiety, nervousness, tremors, headache, hyperglycemia, hypokalemia, hypotension and, rarely, pulmonary edema.[9] WP
• Fetal – tachycardia and hypoglycemia.[10] WP

Pharmacology

Pharmacology

The tertiary butyl group in terbutaline makes it more selective for β₂ receptors. Since there is no hydroxy group on position 4 of the benzene ring, the molecule is less susceptible to metabolism by the enzyme catechol-O-methyl transferase.[11] WP

Legal status

Athletics

As with all β2-adrenergic receptor agonists, terbutaline is on the World Anti-Doping Agency's list of prohibited drugs, except when administered by inhalation and a Therapeutic Use Exemption (TUE) has been obtained in advance. WP

Brand names

Brand names include Astherin, Bronclyn, Brethine, Bricanyl, Brethaire, Marex, Terasma, and Terbulin. WP

Chemistry

Formula

C12H19NO3 PC

CAS number

23031-25-6 PC

Molar mass (g/mol)

225.28 PC

IUPAC name (computed by PubChem)

5-[2-(tert-butylamino)-1-hydroxyethyl]benzene-1,3-diol PC

SMILES

CC(C)(C)NCC(C1=CC(=CC(=C1)O)O)O PC

InChIKey

XWTYSIMOBUGWOL-UHFFFAOYSA-N PC

PubChem CID

5403

Harm reduction information

No harm reduction data is on file for this compound yet. That means no dose, timing or combination data from PsychonautWiki or TripSit. Please don't guess a dose from similar compounds. If you have taken it and feel unwell, contact emergency services or a poison control center.

User reports

Pop culture

No references added yet.

Sources

1. Journal / agency WHO. Antenatal administration of corticosteroids for women at risk of preterm birth
2. Other Most Popular E-mail Newsletter. 18 February 2011
3. Journal / agency FDA warns against certain uses of asthma drug terbutaline for preterm labor
4. Other Fischer J, Ganellin CR. Analogue-based Drug Discovery. 2006
5. Other World Health Organization. World Health Organization model list of essential medicines: 22nd list (2021). 2021
6. Journal / agency Mohamed Ismail NA, Ibrahim M, Mohd Naim N, Mahdy ZA, Jamil MA, Mohd Razi ZR. Nifedipine versus terbutaline for tocolysis in external cephalic version. International Journal of Gynaecology and Obstetrics. September 2008. doi:10.1016/j.ijgo.2008.04.010 · PMID 18554601
7. Journal / agency Goldenberg RL. The management of preterm labor. Obstetrics and Gynecology. November 2002. doi:10.1016/S0029-7844(02)02212-3 · PMID 12423870
8. Journal / agency FDA Drug Safety Communication: New warnings against use of terbutaline to treat preterm labor. 17 February 2011
9. Other Shen H. Illustrated Pharmacology Memory Cards: PharMnemonics. 2008
10. Other Terbutaline: Drug information
11. Other Mehta A. Medicinal Chemistry of the Peripheral Nervous System–Adrenergics and Cholinergics their Biosynthesis, Metabolism, and Structure Activity Relationships. 1992

Text and values on this page are quoted from Wikipedia (CC BY-SA 4.0), PubChem (public domain). Each value links to the exact revision it came from.