Phenylpropanolamine

Phenylpropanolamine (PPA) is a drug of the decongestant and also as an appetite suppressant. In veterinary medicine, it is used to control urinary incontinence in dogs.

Chemistry

There are four optical isomers of phenylpropanolamine: d- and l-norephedrine, and d- and l-norracemic mixture of d,l-norephedrine is usual.

Just as ephedrine is chemically methcathinone.

Phenylpropanolamine was also used for the illicit synthesis of other stimulant drugs such as 4-methylaminorex, and since phenylpropanolamine was withdrawn from use in humans in the early 2000s (although it is still sold for some veterinary applications) it is now much less available, and this in turn has meant that phenmetrazine and 4-methylaminorex have largely disappeared from the illicit market.

Phenylpropanolamine can be made from cathinone.

Side effects

A scientific study^[1] found an increased risk of hemorrhagic stroke in women who used phenylpropanolamine, although it is not clear which isomer is to blame. A study at the Yale University School of Medicine in 1999 had produced similar results.[1] Reports of cases of hemorrhagic strokes in PPA users had been circulating since the 1970s.

A report from the Dept. of Psychiatry, F. Edward Hebert School of Medicine, Bethesda, Maryland in Pharmacopsychiatry^[2] states:

We have reviewed 37 cases (published in North America and Europe since 1960) that received diagnoses of acute mania, paranoid schizophrenia, and organic psychosis and that were attributed to PPA product ingestion. Of the 27 North American case reports, more reactions followed the ingestion of combination products than preparations containing PPA alone; more occurred after ingestion of over-the-counter products than those obtained by prescription or on-the-street; and more of the cases followed ingestion of recommended doses than overdoses.

Failure to recognize PPA as an etiological agent in the onset of symptoms usually led to a diagnosis of schizophrenia or mania, lengthy hospitalization, and treatment with substantial doses of neuroleptics or lithium.

Legal control

The US

In November 2000, the norephedrine in Table I of United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances^[5]

Because of its potential use in methamphetamine manufacture, it is controlled by the Combat Methamphetamine Epidemic Act of 2005. It is still available for use in dogs.

Europe

In Europe, PPA is still available in prescription decongestants such as Rinexin® ^[6] as well as over-the-counter medication such as Wick DayMed®.

See also

• phenethylamines
• Cathine
• ephedrine
• pseudoephedrine
• cathinone
• methcathinone
• amphetamine
• methamphetamine
• phenmetrazine
• 4-methylaminorex

References

1. ^ http://content.nejm.org/cgi/content/abstract/343/25/1826 Phenylpropanolamine and the Risk of Hemorrhagic Stroke], Kernan et al., 2000 N Engl J Med 343:1826-1832
2. ^ http://ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&list_uids=3060884 Psychiatric side effects attributed to phenylpropanolamine, Pharmacopsychiatry 1988 Jul; 21(4):171-81
3. ^ http://www.fda.gov/cder/drug/infopage/ppa/advisory.htm Food and Drug Administration Public Health Advisory, "Safety of Phenylpropanolamine", www.FDA.gov
4. ^ http://www.fda.gov/cder/drug/infopage/ppa/ FDA moves PPA from OTC
5. ^ http://www.unodc.org/unodc/en/document_1999-12-21_1.html Implementation of the international drug control treaties: changes in the scope of control of substances, Commission on Narcotic Drugs, Forty-third session, Vienna, 6-15 March 2000.
6. ^ http://www.fass.se/LIF/produktfakta/artikel_produkt.jsp?NplID=19790406000053&DocTypeID=3&UserTypeID=0, Rinexin in Farmaceutiska Specialiteter i Sverige - the Swedish official drug catalog.(in Swedish)