Phenylpropanolamine
Phenylpropanolamine (PPA) is a drug of the phenethylamine family used in bronchial and nasal decongestants, and also as an appetite suppressant. There are four optical isomers of phenylpropanolamine: d- and l-norephedrine, and d- and l-norpseudoephedrine. D-norpseudoephedrine is also known as cathine, and occurs naturally in the stimulant plant Catha edulis (khat). This isomer is commonly used in European medications described as "phenylpropanolamine", whereas in the United States a racemic mixture of d,l-norephedrine is usual. A scientific study (Kernan et al. 2000) found an increased risk of hemorrhagic stroke in women who used phenylpropanolamine, although it is not clear which isomer is to blame. In November 2000, the FDA issued a public health advisory against the use of the drug.
