Gramine (aka donaxine) is a naturally occurring indole alkaloid that can be found in several plant species. It is toxic to many organisms and may be a natural defense mechanism for these plants. Gramine has been found to act as an agonist of the adiponectin receptor 1 (AdipoR1) which plays an important role in the suppression of metabolic disorders that can result in type 2 diabetes, obesity, and atherosclerosis.

Dimethocaine (DMC, larocaine), a synthetic derivative of cocaine, is a widely distributed "legal high" consumed as a "new psychoactive substance" (NPS), originally was used in the 1930s as an anesthetic, primarily in dentistry, ophthalmology, and otolaryngology. This drug completely inhibits dopamine transporter and has had the potential for abuse. Dimethocaine is intended for forensic and research purposes.