Hexoprenaline

Legal statusLegal status Pharmacokinetic dataBioavailability5–11% (T_max = 2 hours)MetabolismCOMT (slow O-methylation)Elimination half-life~50 minutes (if taken orally)ExcretionFeces (~90%)^[1]IdentifiersCAS NumberPubChem CIDDrugBankChemSpiderUNIIKEGGCompTox Dashboard (EPA)Chemical and physical dataFormulaC₂₂H₃₂N₂O₆Molar mass420.506 g·mol⁻¹3D model (JSmol)ChiralityRacemic mixture ^NY (what is this?)  (verify)

Hexoprenaline is a selective β₂ adrenergic receptor agonist used in the treatment of asthma.^[2] Hexoprenaline is also used in some countries (such as Russia and Switzerland) as a tocolytic agent (i.e., labor suppressant), with the most common trade name being Gynipral.^[3][4] It is not approved by the United States Food and Drug Administration.

Contraindications

When used as a tocolytic, hexoprenaline is contraindicated in:

• Hyperthyroidism
• Cardiovascular diseases, e.g. cardiac arrhythmias, tachycardia, myocarditis, mitral valve disease and aortic stenosis
• Ischemic heart disease
• Hypertension
• Angle-closure glaucoma
• Placental abruption, vaginal bleeding and inflammatory diseases of internal genitalia (such as endometritis)
• Shock
• First trimester of pregnancy
• Breastfeeding^[1][3]

It should be used with caution in people with gestational diabetes.

Drug-drug interactions

When concomitantly administered:

• Beta blockers reduce or neutralize therapeutic effects of hexoprenaline
• Methylxanthines (caffeine, theobromine, theophylline) increase its action
• General anaesthetics (e.g., halothane) and adrenergic receptor agonists may increase the risk of cardiovascular side effects, such as arrhythmia

Hexoprenaline is contraindicated for use with monoamine oxidase inhibitors (MAOIs), tricyclic antidepressant (TCAs), ergot alkaloids, and dihydrotachysterol.^[3]

References