Pfizer may face many more lawsuits related Zithromax widely known as Z-Pack.  Zithromax is an antibiotic drug manufactured by Pfizer Inc. It’s being linked with several severe side effects including cardiovascular problems. Zithromax or Azithromycin was approved by FDA for treatment of acute bacterial exacerbations of chronic pulmonary disease, acute bacterial sinusitis, community-acquired pneumonia, pharyngitis, tonsillitis, uncomplicated skin and skin structure infections, urethritis and cervicitis and genital ulcer disease. It is also used to treat bacterial infections such as middle ear infection, pneumonia, tonsillitis and strep throat in children.

New York Times reported that around 55.3 million prescriptions for azithromycin were written in theUnited Stateslast year. Its use regimen is easier compared to other antibiotics; therefore it is prescribed over amoxicillin, another common antibiotic. Patients need to take fewer pills for shorter period of time compared to other antibiotic drugs.

A study was published in ‘The New England Journal of Medicine’ on 17th May 2012 related to Zithromax side effects. The study revealed use of Zithromax could increase occurrence of cardiovascular diseases in patients using it compared to other antibiotic medicines. It also revealed that patients taking Azithromycin or Zithromax showed one and a half times the odds of sudden death from cardiovascular causes compared to other similar antibiotic. The risk was higher in patients having existing cardiovascular conditions.

The study was conducted on 350,000 Medicaid patients who were on Azithromycin or Zithromax from 1992 to 2006. Data from all these patients were analysed. Study revealed that 47 more deaths were reported for every million people taking Zithromax in place of amoxicillin. The patients already having heart problems and using Zithromax showed more than 245 more deaths per million, compared to other similar antibiotics. Patients who are suffering from or have suffered from heart failure, diabetes, previous heart attacks, prior bypass surgery or with stents implanted are at higher risk. They can experience cardiac arrhythmia or fatal abnormal heartbeats called arrhythmia.

The study pushed The U.S. Food and Drug Administration to issue a notification on the same day. FDA issued a statement and announced that it’s reviewing the results of the study and will inform the public about it as soon as it completes its review. In March 2012, the warning label for Zithromax, which contains azithromycin in an extended release oral suspension, was revised. The information regarding the risk of QT interval prolongation, leading to heart arrhythmia and other potentially life-threatening heart problems were included on the label of the drug.

Use of Zithromax could cause QT interval prolongation. Patients with history of a heart rhythm disorder or prolonged QT syndrome are at higher risk of fatal consequences. Use of Zithromax could worsen their condition. Patients suffering from heart failure, slow heartbeat, QT prolongation in the EKG, family history of certain heart problems are at higher risk. Patients suffering from low levels of potassium or magnesium in the blood are also at increased risk.

This has triggered many Zithromax side effects lawsuit against Pfizer. Patients are asking for compensation for medical bills, pain and suffering, lost wages and other injuries. These lawsuits accuse Pfizer that it was well aware of the potential side effects of its antibiotic drug Zithromax, but failed to provide adequate warning to the patients. Zithromax is a widely used antibiotic, so there are chances that numerous lawsuits may be filed against Pfizer related to its severe side effect.