“Z-Pack” Antibiotic May Trigger Fatal Heart Issues, FDA Warns

Dangerous drug lawyers at Pintas & Mullins Law Firm join the FDA in warning American patients that a popular antibiotic, sold as Zmax or Zithromax, may lead to life-threatening heart rhythms in some. The antibiotic, manufactured by Pfizer, is sometimes referred to as a “Z-Pack.”

Azithromycin, the generic form of the pill, is prescribed to patients with common bacterial infections, such as pneumonia, bronchitis, and ear infections. In its warning, the FDA cited a study published in the New England Journal of Medicine in May 2012, which was sponsored by the National Heart, Lung, and Blood Institute. The study found that, per one million patients treated with Zithromax, nearly 50 of those would experience a heart-related death within five days. This was in comparison to other antibiotics, such as amoxicillin.

Alarmingly, the risk of heart-related death was similar in patients taking the antibiotic levofloxacin, which is the generic for Levaquin. Although the overall risk is somewhat low, patients with known heart issues or problems are urged to steer clear of these medications, as additional research is currently being conducted.

Following the 2012 study, the FDA issued a statement saying it was aware of these results, would review the study, and would communicate any new information as soon as it was made available. The study took 14 years to conduct, between 1992 and 2006. In those years, researchers at Vanderbilt University studied about 540,000 Tennessee Medicaid patients who were receiving a range of antibiotics.

They found that the risk of death among those taking Zithromax was more than double that of patients taking other popular antibiotics. All patients studied started the treatments with relatively the same risk factors for heart trouble, were age 50 on average, and were not hospitalized for their ailments. Most patients were being treated for common illnesses, such as sinus infections.

As stated, the study was conducted on Medicaid patients, who generally have greater disability and lower incomes than the average patient not using the program. Dr. Wayne Ray, a Vanderbilt medical professor who was involved in the study, stated that more research must be conducted on patients of the general population to determine if the results are the same.

Pfizer’s Zithromax is one of the nation’s best-selling antibiotics – sales totaled $464 million in 2011. It is more expensive than most other antibiotics, yet is so popular because it only requires five days of continuous treatment (other antibiotics typically take seven to ten days). It has been available on US markets for more than two decades, and American doctors doled out more than 55 million prescriptions in 2011.

Researchers decided to study this drug because of mounting evidence linking it with cardiovascular adverse events, and because two antibiotics in the same class as Zithromax have recently been associated with sudden heart-related deaths: erythromycin and clarithromycin.

Other doctors are saying that these results raise questions about the long-term use of the antibiotic. Long-term use has recently been suggested to help patients with severe lung disease, and additional research needs to be done to determine if the risks of cardiovascular effects is the same in patients using the drug for this purpose.

Pfizer also issued a statement after the study’s release, stating the company would thoroughly review the research and continue to monitor the safety and efficacy of the medication. According to the FDA, the drug can cause abnormal changes in the heart’s electrical activity, which can lead to irregular heart rhythms that are potentially fatal.

Researchers stated that exactly how the drug initiates the abnormal rhythms is not yet known. Other patients at higher risk of these abnormal changes include those with low potassium or magnesium blood levels, diabetes, and those using certain drugs to treat arrhythmias.

Antibiotics have been significantly overprescribed by doctors in recent years, which have led to the emergence of new bacterial strains that are resistant to drugs. With this new information, patients at high risk for or with past history of heart issues should not be prescribed the Z-pack, erythromycin, levofloxacin, or clarithromycin.

If you or someone you love was prescribed these dangerous antibiotics and suffered a serious cardiovascular incident, you may be entitled to compensation. Antibiotics lawyers at Pintas & Mullins Law Firm have extensive experience advocating for victims of dangerous drugs and their families, and are currently evaluating potential dangerous prescription drug claims.


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