Propoxyphene, derived from opium, is categorized in the same family of drugs as morphine, heroin, OxyContin, and Fentanyl. It is also known as Darvon, Darvocet, Wygesic, Balacet, or Propacet. According to the federal Drug Enforcement Agency (DEA), Darvon is one of the top 10 most abused prescription drugs. Darvon, a mild narcotic painkiller, and other prescriptions containing propoxyphene, are in danger of being taken off the market because they are addictive and not any more effective at relieving pain than aspirin.

Propoxyphene is used by some abusers to tide themselves over when they cannot obtain their preferred drug, such as heroin. Many abusers grow dependent on Darvon and other propoxyphene products after their doctors prescribe them for pain relief, diarrhea, or restless leg syndrome. Doctors typically prescribe 65 ml of propoxyphene per day. Higher tolerance can lead to abusers taking 250 to 400 ml per day, causing health risks.

Withdrawal symptoms of abusers are similar to those produced by other opiates. The flu-like withdrawal symptoms include: muscle aches, headaches, sweats, chills, anxiety and insomnia. Propoxyphene dependency and withdrawal can also produce psychological problems, such as anxiety, depression, and drug cravings.