Medetomidine is a synthetic drug used as both a surgical anesthetic and analgesic often used as the hydrochloride salt medetomidine hydrochloride. It is a crystalline white alpha-two adrenergic agonist[1] that can be administered as an intravenous drug solution with sterile water. It is often used in combinations with opioids (butorphanol, buprenorphine etc.) as premedication (before a general anaesthetic) in healthy cats and dogs. It can be given by intramuscular injection (IM), subcutaneous injection (SC) or intravenous injection (IV). When delivered intravenously, a significantly decreased dose is used. Some authors suggest a sublingual route is also effective.Medetomidine can be used as an antifouling substance in marine paint. It is mainly effective against barnacles, but has also shown effect on other hard fouling like tube worms.