Johnson & Johnson has added a safety warning to the label for its Duragesic (fentanyl) patch for chronic pain to highlight possible misuse and abuse associated with the product.

In a “Dear Doctor” letter dated June 2005 but posted on the US Food and Drug Administration’s website late last week, the company’s Janssen subsidiary said that the changes came as part of the agency’s bid to increase awareness of safety issues, including misuse and abuse, associated with so-called opioid drugs such as Duragesic. Opioid drugs, including morphine, have the highest potential for misuse and abuse, and have also been associated with fatal overdoses, due to respiratory problems.

The label now states that the product should only be used in patients who are already receiving opioid therapy, or who have demonstrated opioid tolerance at least equivalent to the corresponding Duragesic strength. All patients should also be monitored for signs of abuse and addiction, the letter stated, as “the use of opioid analgesic products carried the risk of addiction even under appropriate medical use.” It also includes new information on interactions with central nervous system depressants, alcohol and “drugs of abuse.”