Methylergometrine

Obstetric use Methylergometrine is a smooth muscle constrictor that mostly acts on the uterus. It is most commonly used to prevent or control excessive bleeding following childbirth and spontaneous or elective abortion, and also to aid in expulsion of retained products of conception after a missed abortion (miscarriage in which all or part of the fetus remains in the uterus) and to help deliver the placenta after childbirth. It is available as tablets or injection (IM or IV) or in liquid form to be taken orally. Migraine Methylergometrine is sometimes used for both prevention and acute treatment of migraine. It is an active metabolite of methysergide. In the treatment of cluster headaches, methylergometrine has been initiated at a dose of 0.2 mg/day, rapidly increased to 0.2 mg three times per day, and increased to a maximum of 0.4 mg three times per day. ==Contraindications==

Methylergometrine is contraindicated in patients with hypertension and pre-eclampsia. ==Side effects==

Adverse effects include: • Nausea, vomiting, and diarrhea • Dizziness • Pulmonary hypertension • Coronary artery vasoconstriction • Severe systemic hypertension (especially in patients with pre-eclampsia) • Convulsions In excessive doses, methylergometrine can also lead to cramping, respiratory depression and coma. == Interactions ==

Methylergometrine likely interacts with drugs that inhibit the liver enzyme CYP3A4, such as azole antifungals, macrolide antibiotics and many HIV drugs. It can also increase constriction of blood vessels caused by sympathomimetic drugs and other ergot alkaloids. ==Pharmacology==

Pharmacodynamics Methylergometrine is an agonist or antagonist to serotonin, dopamine, and α-adrenergic receptors. Its specific binding and activation pattern on these receptors leads to a highly, if not completely, specific contraction of smooth uterus muscle via serotonin 5-HT2A receptors, while blood vessels are affected to a lesser extent compared to other ergot alkaloids. Methylergometrine is an agonist of the serotonin 5-HT2B receptor and may be linked to cardiac valvulopathy. Pharmacokinetics The bioavailability of methylergometrine is 60% via oral administration and 78% by intramuscular injection. It is metabolized in the liver, with extensive first-pass metabolism. The elimination half-life of the drug is 3.4hours. It is eliminated mainly via metabolism and then excreted. ==Natural occurrence==

Previously thought to be an exclusively synthetic compound, it has been reported to occur naturally in Argyreia nervosa (Hawaiian baby woodrose). The drug is on the World Health Organization's List of Essential Medicines. ==Chemistry==

Methylergometrine, also known as d-lysergic acid 1-butanolamide, is a derivative of the ergoline and lysergamide classes and is structurally related to ergometrine (d-lysergic acid β-propanolamide) and lysergic acid diethylamide (LSD). ==History==

Methylergometrine was first described in the scientific literature by 1945. ==Society and culture==

Recreational use Methylergometrine is a synthetic analogue of ergometrine, a psychedelic alkaloid found in ergot, and many species of morning glory. Methylergometrine is a member of the ergoline family and chemically similar to LSD, ergine, ergometrine, and lysergic acid. According to Jonathan Ott, methylergometrine produces LSD-like psychedelic effects at doses of 2 mg and above. Clinical effectiveness of methylergometrine as a medication occurs around 200μg, which is 10times lower than the hallucinogenic threshold. United States Methylergometrine is not an explicitly controlled substance in the United States. ==See also==