Melatonin is a hormone that is naturally produced in the body and helps regulate sleep patterns. There are several synonyms for melatonin, including N-acetyl-5-methoxytryptamine, MEL, and MLT. These terms are often used interchangeably with melatonin in scientific and medical literature. Other less common synonyms for melatonin include Pinealatonin, Melatonina, and Circadin. Some alternative treatments and supplements marketed to promote better sleep quality may also contain melatonin under various names. Understanding the synonyms for melatonin can be helpful in identifying its presence in medications or supplements and in discussing treatments with healthcare providers.