Chlorphentermine (trade names Apsedon, Desopimon, Lucofen) is an appetite suppressant of the phenethylamine class. Developed in 1962, it is the 4-chloro derivative of the better known appetite suppressant phentermine, which is still in current use.
Chlorphentermine itself is a relatively weak stimulant with little abuse potential, but is classed as a Schedule III drug in the USA due mainly to its similarity to other appetite suppressants such as diethylpropion which have been more widely abused. It is no longer used due mainly to safety concerns, as it has a serotonergic effects profile similar to other withdrawn appetite suppressants such as fenfluramine and aminorex which were found to cause pulmonary hypertension and cardiac fibrosis following prolonged use.