Tramadol hydrochloride (trademarked as Conzip, Ryzolt, Ultracet, Ultram in the USA, Ralivia and Zytram XL in Canada) is a centrally acting synthetic analgesic used to treat moderate to moderately severe pain. The drug has a wide range of applications, including treatment of rheumatoid arthritis, restless legs syndrome, motor neurone disease and fibromyalgia. It was launched and marketed as Tramal by the German pharmaceutical company Grnenthal GmbH in 1977. Tramadol is a very weak -opioid receptor agonist, induces serotonin release, and inhibits the reuptake of norepinephrine. Tramadol is converted to O-desmethyltramadol, a significantly more potent -opioid agonist. The opioid agonistic effect of tramadol and its major metabolite(s) is almost exclusively mediated by such -opioid receptors.
Contributions by Beetstra, Techelf, and Davidruben.