Fentanyl is an opioid analgesic, first synthesized in Belgium in the late 1950s, with an analgesic potency of about 80 times that of morphine. It was introduced into medical practice in the 1960s as an intravenous anesthetic under the trade name of Sublimaze. Fentanyl has an LD50 of 3.1 mg/kg.

Analogues

The pharmaceutical industry has developed several analogues of fentanyl: -

1. alfentanil (Alfenta), an ultra-short (5-10 minutes) acting analgesic,
2. sufentanil (Sufenta), a potent analgesic (5 to 10 times more potent than fentanyl) for use in heart surgery.
3. remifentanil, currently the shortest acting opioid, has the benefit of rapid offset, even after prolonged infusions.
4. carfentanil (Wildnil) is an analogue of fentanyl with an analgesic potency 10,000 times that of morphine and is used in veterinary practice to immobilize certain large animals.

Therapeutic use

Today, fentanyls are extensively used for anesthesia and analgesia. Duragesic is a fentanyl transdermal patch used in chronic pain management. Actiq is a recently-developed solid formulation of fentanyl citrate on a stick that dissolves slowly in the mouth for transmucosal absorption. Actiq is intended for opiate-tolerant individuals and is effective in treating breakthrough cancer pain. The unit is a raspberry-flavored lozenge on a stick which is swabbed inside the mouth and gums to release the fentanyl quickly into the system; if the medication is swallowed, it is not effective, so as much of it must be placed on the mucosal surface as possible.

Fentanyl is frequently given intrathecally as part of spinal anesthesia or epidurally for epidural anesthesia and analgesia.

Illicit use

Illicit use of pharmaceutical fentanyls first appeared in the mid-1970s in the medical community and continues to be a problem in the United States. United States authorities classify fentanyl as a narcotic. To date, over 12 different analogues of fentanyl have been produced clandestinely and identified in the U.S. drug traffic. The biological effects of the fentanyls are indistinguishable from those of heroin, with the exception that the fentanyls may be hundreds of times more potent. Also, fentanyl has a shorter duration than heroin does. Fentanyls are most commonly used by intravenous administration, but like heroin, they may also be smoked or snorted. One common street name for fentanyl is china white.

Actiq has begun to appear on the streets under the street name of "percopop,", although the cost of the drug for actual patients is more than $30 USD for each unit, with the black market cost is at least ten times that.

Notoriety

In 1979, fentanyl was at the center of a major scandal in the sport of horse racing, as tests of urine samples revealed the presence of the drug in hundreds of thoroughbred race horses, most of which had raced at East Coast racetracks (in addition to its analgesic effects, fentanyl has a powerful stimulant effect on horses). The scandal resulted in the horses in question being disqualified from races in which they had either won or had earned a share of the purse, and the purse money was redistributed; some owners and trainers of the drugged horses were also fined and/or suspended.

The incapacitating agent used by Russian security forces in the October 2002 Moscow theatre siege incident was a fentanyl derivative, according to a statement issued by the Russian Health Minister Yuri Shevchenko.

External links

• Drug description, including suspected use in a variety of situations.
• US DOJ information: fentanyl
• BBC news report
• MPTP and drug-induced Parkinson's disease
• The Vaults of Erowid - MPTP