4-Fluoromethamphetamine (4-FMA) is a stimulant drug related to methamphetamine and 4-fluoroamphetamine. It has been reported to be sold as a designer drug, but little is known about its pharmacology or toxicology. Anecdotal user reports however mention a high risk of physical dependence and serious withdrawal symptoms, such as fever and a tendency for dissociation, which last about a week.