The reason cited by the FDA for its call for a market withdrawal of all products containing the opiod propoxyphene was a recent study that determined the drug could cause potentially fatal heart rhythm abnormalities. While the Darvon recall was shocking news to some, it was a frustratingly late admission to others, most notably the consumer advocacy group Public Citizen, which has been one of the most vocal opponents of propoxyphene since it petitioned to have the drug banned first in 1978 and again in 2006.
In fact, the petition sent to the FDA by Public Citizen on February 28, 2006, provides clear evidence of the cardiac toxicity of propoxyphene. This point will no doubt be raised if and when a Congressional investigation into the FDA’s delayed action, which the group has asked for, is undertaken. The data presented by the group pointing to propoxyphene’s extreme health risks are also likely to play a role in litigation against makers of the drug. In two cases filed to date against Xanodyne Pharmaceuticals, Inc., maker of Darvon and Darvocet, the plaintiffs allege that the manufacturer failed to warn doctors and consumers despite a wealth of evidence that indicated the drugs could cause potentially fatal heart complications.
Turning to Public Citizen’s 2006 petition, one finds many important points, several of which are presented here. The first is that propoxyphene has an extremely thin margin of safety. Secondly, the group draws attention to the fact that propoxyphene is a relatively weak painkiller. And finally, the petition argues that propoxyphene has characteristics typical of other narcotics that can contribute to the risk of accidental overdose.
Propoxyphene’s narrow margin of safety refers to the fact that the drug can be toxic when taken in amounts even slightly above the recommended dose. For example, at four times the standard dose, propoxyphene can lead to a significant drop in heart rate and breathing. At six times the recommended dose, the drug can cause toxic psychosis and seizures. Obviously, this thin divide between efficacy and toxicity is troublesome. But when considered alongside the drug’s ineffectiveness and addiction potential, it becomes clear that propoxyphene is a truly dangerous drug.
Around the time Darvocet was released to the U.S. market (1972), some researchers concluded that propoxyphene was no more effective at pain relief than two aspirin (a few actually gave the nod to aspirin). Due to this analgesic shortcoming, patients who are prescribed propoxyphene for the treatment of mild to moderate pain may increase their dosage to achieve the desired result. Owing to its narrow margin of safety, this could result in cardiac toxicity and ultimately, a heart attack, stroke, or another deadly coronary side effect.
Another factor that exacerbates propoxyphene’s thin safety margin is its narcotic properties. Like other drugs of this type, propoxyphene has the potential to create tolerance, dependency, physical dependence, and psychological dependence. When a patient becomes tolerant to a drug, he or she requires an increasingly stronger dose to achieve the same effect. Similar to the previous example, a patient who increases his or her dosage because of tolerance runs the risk of ingesting a toxic amount of propoxyphene and experiencing heart problems. In addition, because it is addictive, some patients abuse propoxyphene, which can also have deadly results.
Taken as a whole, propoxyphene’s risk factors lead to many accidental overdose deaths. According to the Drug Abuse Warning Network (DAWN), more than 4 out of 10 propoxyphene-related deaths are accidental (a percentage greater than the number of suicide deaths linked to the drug). Of these, more than 75 percent are caused by cardiac toxicity. The risk of overdose increases significantly when a “cocktail” of alcohol (and/or other depressants) and propoxyphene is consumed.
It remains to be seen what role, if any, this and other information about the dangers of propoxyphene will play in upcoming litigation against Xanodyne and other drugmakers. It appears, however, that there is sufficient evidence to prove that drug manufacturers failed to warn the public about the potentially deadly cardiac side effects of propoxyphene and placed profits over safety by failing to voluntarily issue a Darvocet recall years ago.
If courts reach a similar conclusion, it should mean that injury victims will receive compensation for monetary losses, pain and suffering, and other damages. If, in the course of taking Darvon, Darvocet, or another drug containing propoxyphene, you suffered a heart attack or stroke, or you developed an arrhythmia, atrial fibrillation, an irregular heartbeat, or other coronary issues, contact the Rottenstein Law Group today to find out whether you are eligible to file a Darvocet lawsuit. For a complimentary case review, fill out this form or call 1 (888) 976-8529.