Health Canada’s Therapeutic Products Directorate (TPD) is the Canadian federal authority that regulates pharmaceutical drugs and medical devices for human use.
The agency is the equivalent of the U.S. Food and Drug Administration (FDA). Both have now issued similar warnings concerning the potentially deadly interaction between one particular slow-release “opioid” painkiller, Palladone XL, and alcohol in any amount.
The two agencies have taken different approaches to the problem, however. On July 13, the FDA asked Palladone’s maker, Purdue Pharma L.P., to withdrawn the drug from the market in the United States. No mention was made in the FDA releases of other opioids posing the same risk when combined with alcohol. Purdue Pharma voluntarily agreed to suspend sales of Palladone in the United States.
In ordering the withdrawal of Palladone, the FDA released a series of announcements including an ALERT (http://www.fda.gov/cder/drug/infopage/palladone/default.htm), a PUBLIC HEALTH ADVISORY (http://www.fda.gov/cder/drug/advisory/palladone.htm), QUESTIONS AND ANSWERS (http://www.fda.gov/cder/drug/infopage/palladone/palladoneQA.htm), and an ALERT FOR HEALTHCARE PROFESSIONALS (http://www.fda.gov/cder/drug/InfoSheets/HCP/hydromorphoneHCP.htm).
Taking a different approach, the newly issued advisory by Health Canada does not order the recall of Palladone. Instead, the Canadian warning of the potentially fatal interaction extends to all opioids based on the premise that “there may be a possibility that these products could react in the same way when taken with alcohol.”
Health Canada has requested the manufacturers of other similar drugs to provide data on their products’ interaction with alcohol within six months.
Palladone XL has not been shipped to Canada since December 2004 and there are currently no supplies of the drug on the Canadian market.
The danger posed by the combination of any amount of alcohol and Palladone XL comes about because the slow-release form of hydromorphone contained in the drug can be overridden by the introduction of alcohol. This can cause an effect known as “dose dumping” where the hydromorphone is released quickly into the blood in dangerous levels rather than over the intended 24-hour period.
Slow-release drugs are also marketed as extended release, time-release, controlled release, and controlled delivery and often carry SR, XR, XL, SRC, and SRT after the brand name. Other slow-release opioids currently on the market in Canada include: Hydromorph Contin (hydromorphone); Kadian SRC (morphine sulfate); M.O.S. SR (morphine hydrochloride); M-Elson (morphine sulfate); MS Contin SRT (morphine sulfate); Oxycontin SRT (oxycodone); PMS-Morphine Sulfate SR (morphine sulfate); Ratio-Morphine SR (morphine sulfate); Roxanol SR (morphine sulfate); and Zomorph (morphine sulfate).
It remains unclear whether alcohol may also affect the slow-release mechanisms in these other opioids thereby causing “dose dumping” similar to what has been found with Palladone XL. Obviously, anyone taking any of these powerful narcotic drugs should not combine them with alcohol under any circumstances and especially until further data regarding the interaction is forthcoming.