Fenfluramine (3-trifluoromethyl-N-ethylamphetamine, trade names Pondimin, Ponderax and Adifax) is a drug that, along with phentermine, was part of the anti-obesity medication Fen-phen.

Dexfenfluramine, marketed as dexfenfluramine hydrochloride under the name Redux, is a serotonergic anorectic drug: it reduces appetite by increasing the amount of extracellular serotonin in the brain. It is the d-enantiomer of fenfluramine and is structurally similar to amphetamine, but lacks any psychologically stimulating effects.

Levofenfluramine (INN), or (-)-3-trifluoromethyl-N-ethylamphetamine, also known as (-)-fenfluramine or (R)-fenfluramine, is a drug of the amphetamine family that, itself (i.e., in enantiopure form), was never marketed. It is the levorotatory enantiomer of fenfluramine, the racemic form of the compound, whereas the dextrorotatory enantiomer is dexfenfluramine. Both fenfluramine and dexfenfluramine are anorectic agents that have been used clinically in the treatment of obesity (and hence, levofenfluramine has been as well since it is a component of fenfluramine). However, they have since been discontinued due to reports of causing cardiovascular conditions such as valvular heart disease and pulmonary hypertension, adverse effects that are likely to be caused by excessive stimulation of 5-HT_2B receptors expressed on heart valves.

Fenfluramine (3-trifluoromethyl-N-ethylamphetamine, trade names Pondimin, Ponderax and Adifax) is a drug that, along with phentermine, was part of the anti-obesity medication Fen-phen.

Dexfenfluramine, marketed as dexfenfluramine hydrochloride under the name Redux, is a serotonergic anorectic drug: it reduces appetite by increasing the amount of extracellular serotonin in the brain. It is the d-enantiomer of fenfluramine and is structurally similar to amphetamine, but lacks any psychologically stimulating effects.

Levofenfluramine (INN), or (-)-3-trifluoromethyl-N-ethylamphetamine, also known as (-)-fenfluramine or (R)-fenfluramine, is a drug of the amphetamine family that, itself (i.e., in enantiopure form), was never marketed. It is the levorotatory enantiomer of fenfluramine, the racemic form of the compound, whereas the dextrorotatory enantiomer is dexfenfluramine. Both fenfluramine and dexfenfluramine are anorectic agents that have been used clinically in the treatment of obesity (and hence, levofenfluramine has been as well since it is a component of fenfluramine). However, they have since been discontinued due to reports of causing cardiovascular conditions such as valvular heart disease and pulmonary hypertension, adverse effects that are likely to be caused by excessive stimulation of 5-HT_2B receptors expressed on heart valves.