From Geriatric Pharmacy Intern Seth Rana PharmD(c) Palm Beach Atlantic University School of Pharmacy
Propoxyphene has been used to treat pain for over 50 years and it is known by its brand name Darvon and Darvocet (when combined with acetaminophen). The food and drug administration (FDA) recently added a boxed warning to propoxyphene for deaths related to overdose. It already carried a boxed warning for patients who are suicidal or prone to addiction since propoxyphene works on the opioid receptors causing dependence and central nervous system (CNS) depression. FDA is also requiring health professionals to dispense a medication guide with prescriptions to inform patients about the warnings and side effects related to propoxyphene. According to FDA, propoxyphene will continue to be available as prescription drug despite these warnings. Propoxyphene is not recommended for the elderly since they are more susceptible to side effects such as: sedation, fatigue, dizziness, constipation, nausea, vomiting, abdominal pain, and shortness of breath. Too much propoxyphene can also affect the liver and may cause dependence. Alcohol should not be consumed while taking propoxyphene and caution is advised before taking other medications causing CNS depressant effects. Propoxyphene’s effectiveness for mild to moderate pain is questionable. FDA’s recent review of Darvocet’s initial drug application states that for chronic pain “there are insufficient data in the literature to assess the analgesic effects of propoxyphene products. According to a pain intensity difference graph by Bauer (included in Darvocet’s new drug application process in 1971), Darvon alone was as effective as acetaminophen (Tylenol). With this information in mind there were approximately 21 million prescriptions written for propoxyphene containing drugs in 2007 according to the FDA. There are far too many prescriptions written for a medication which may be limited in effectiveness while having serious adverse reactions and now black box warnings. According to the FDA, Propoxyphene-containing products can be taken safely when patients take it as directed and when patients are monitored by a healthcare professional. Speak to your senior care pharmacist to find out if medications such as Darvocet are right for you and about the appropriate dose and frequency for taking propoxyphene products.