Oncotonin Melatonin 10 mg by Ecological Formulas is a dietary supplement designed to promote a good night's sleep. The key ingredient in Oncotonin Melatonin 10 mg by Ecological Formulas is melatonin. a hormone normally excreted by the pineal gland located at the base of the brain. If this gland doesn't produce enough melatonin as required by the body. sleep patterns can become irregular. When used at bedtime. this supplement offers a natural alternative to sleep medications that produce unwanted side effects.