In a move to reduce illegal use of the oral prescription analgesic Talwin 50, Winthrop Laboratories, a division of Sterling Drug Inc., has reformulated the drug so that if taken inappropriately, it will give abusers withdrawal-like symptoms rather than a "high."
Talwin 50 (pentazocine hydrochloride), when crushed, dissolved together with the blue tablet tripelennamine (an antihistamine), and injected intravenously, provides a high similar to that of heroin (JAMA [MEDICAL NEWS] 1982;247:409). Several years ago, street people began to use the combination, called "T's and blues," as an alternative to costly heroin.
The new formulation, which just went on the market, contains 50 mg of pentazocine and 0.5 mg of naloxone. Naloxone, a narcotic antagonist, is inactive when taken by mouth and does not affect the safety and efficacy of pentazocine when taken orally as intended, according to Sterling. However, if the new formulation—called Talwin Nx—is misused and taken intravenously, withdrawal