Jan 28, - Liquid Melatonin is a substitute if you do not want to swallow tablets. . In the US today you can buy melatonin only as a supplement and not a drug . Librax), Clnazepam (Klnpin) Clrazepate (Tranxene),Diazepam (Valium), Missing: online. Melatonin sleeping tablets are popular herbal sleep remedies, read more online at Patient. Available as, Modified-release tablets, tablets, capsules, oral liquid medicine This includes any medicines you are taking which are available to buy without a prescription, as well as herbal and complementary medicines. Find patient medical information for Melatonin on WebMD including its uses, effectiveness, side effects and safety, interactions, dosage, user ratings and.