Herb-Drug Interactions: Melatonin

N-(2-(5-Methoxyindol-3-yl)ethyl)acetamide Types, sources and related compounds N- Acetyl-5-methoxytryptamine. Use and indications Melatonin is a hormone that is produced in the pineal gland of the brain and influences the circadian rhythm. Supplements are therefore principally used for treating sleep disturbances and disorders such as jet lag, insomnia, sleep walking, and shift-work sleep disorder. It is also believed to have anticancer and antihypertensive properties, and has been used to treat cluster headaches. Melatonin has also been detected in a large number of plant species, including those used as foods. Concentrations detected have been very variable, the reasons for which are currently uncertain. In addition, the importance of dietary melatonin is unclear. Pharmacokinetics When an oral melatonin supplement 3mg was given to 17 healthy subjects the AUC and maximum serum levels of melatonin were about 18-fold and 100-fold greater, respectively, than overnight endogenous melatonin secretion, although there was a wide variation between individuals.The oral bioavailability was approximately 15% after oral doses of 2 or 4mg, possibly due to significant first-pass metabolism. The half-life has been found Read more […]

Herb-Drug Interactions: Evening primrose oil

Oenothera biennis L. (Onagraceae) Synonym(s) and related species Common evening primrose, King’s cureall, Sun drop, Tree primrose. Oenothera lamarkiana, Onagra biennis (L.) Scop. Pharmacopoeias Evening primrose oil (British Ph 2009, European Ph, 6th ed., 2008 and Supplements 6.1, 6.2, 6.3 and 6.4). Constituents The oil from evening primrose seeds contains the essential fatty acids of the omega-6 series, linoleic acid (about 65 to 85%) and gamolenic acid (gamma-linolenic acid, about 7 to 14%). Other fatty acids include oleic acid, alpha-linolenic acid, palmitic acid and stearic acid. Use and indications Evening primrose oil is used as a food supplement to provide essential fatty acids. It is also used for atopic eczema and mastalgia; however, in the UK licences for two prescription products containing gamolenic acid derived from evening primrose oil were withdrawn in 2002, due to lack of evidence in support of efficacy. Other conditions for which it is used include rheumatoid arthritis, premenstrual syndrome, menopausal symptoms, chronic fatigue syndrome and attention deficit hyperactivity disorder. Evening primrose oil has also been used topically as a cream, for the relief of dry or inflamed skin. Read more […]