Propylhexedrine is most commonly found in Benzedrex inhalers. Benzedrex was first manufactured by Smith, Kline and French after the inhaler, which contained , became unavailable following the placement of amphetamines on the US status (highest abuse potential, yet with accepted medicinal uses). Benzedrex is currently manufactured by B.F. Ascher & Co. Inc. Pharmaceuticals.
propylhexedrine is a volatile, oily liquid at room temperature. The slow vaporization of free base propylhexedrine allows it to be administered via inhalation. Acid salts of propylhexedrine (such as propylhexedrine ) often present as a stable, clear to off-white crystalline powder that readily dissolves in water.
While propylhexedrine is limited in a number of administration routes, attempts to extract the drug from the nasal inhaler and then inject it have been reported. Recreational use by intravenous injection (IV) is dangerous and could result in serious bodily harm or death. IV use of propylhexedrine is known to cause mild side-effects such as as well as some serious (and potentially fatal) effects such as brainstem dysfunction, and deaths have been recorded in the medical literature. Typically, recorded cases of IV use are prepared by forming propylhexedrine in a solution with hydrochloric acid, the solution is then heated to evaporate and the resulting crystals are dissolved in water for injection.
Propylhexedrine is a chiral compound (the α-carbon is chiral), and active ingredient contained in Benzedrex inhalers is ()-propylhexedrine as the free base. ()-Propylhexedrine, also known as levopropylhexedrine, is believed to be the more biologically active isomer of the two. ()-Propylhexedrine can be synthesized from methamphetamine.