Propylhexedrine (Benzedrex, Obesin) is a stimulant drug related to methamphetamine. It is used mainly to provide temporary symptomatic relief of nasal congestion due to colds, allergies and allergic rhinitis. Being a vasoconstrictor used to decongest nasal mucosa, it is administered by inhalation.

Propylhexedrine is most commonly found in over-the-counter Benzedrex inhaler. Benzedrex was first manufactured by Smith, Kline and French after the Benzedrine inhaler, which contained racemic amphetamine, became unavailable following the placement of amphetamines on the U.S. Schedule II status (second highest abuse potential with limited medicinal use). Propylhexedrine has also seen use in Europe as an appetite suppressant under the trade name Obesin and in the anticonvulsant preparation barbexaclone its S-isomer (levopropylhexedrine or L-propylhexedrine) is bonded with phenobarbital for the purpose of offsetting the barbiturate-induced sedation. Levopropylhexedrine is also used as an anorectic under the brand name Eventin.

Kurt Kren (September 20, 1929 - died in Vienna on June 23, 1998) was an Austrian avantgarde filmmaker. He is best known for his involvement with the Vienna Aktionists and the group of films that resulted, although this accounts for only a part of his career, and he later returned to the Structural roots of his third film 3/60: Bäume Im Herbst. Although not a seminal Structural film, 31/75: Asyl is arguably one of the more satisfying films of the movement.

Kurt Kren was born in 1929 in Vienna, Austria to a family of a Jewish father (a bank employee) and German mother. From 1939 till the end of World War II Kren lived in Rotterdam, where he was sent with one of the Children's Transports. In 1947 Kren returned to Vienna, and his father provided him a job at the National Bank.

He began a film career in the early 1950s creating experimental short 8mm films. In 1957 he moved to the 16mm format.

In 1966, Kren participated in the Destruction in Art Symposium in London. In 1968 he visited the USA for the first time, showing his films in New York and St. Louis. After a participation in a happening "Kunst und Revolution" ("Art and Revolution") at the University of Vienna in 1968, Kren's films were confiscated and he was fired from the National Bank.