Could New Use for Zithromax Lead to Increased Cases of Stevens Johnson Syndrome?

San Diego, CAOn the surface, it appears as welcome news; an existing medication that has the potential to be effective in a new indication. However, digging deeper one has to wonder if a perfect storm is on the horizon, given that Zithromax has the potential for use in more people and thus introduces more potential for Zithromax Stevens Johnson Syndrome.

Stevens Johnson Syndrome, or SJS, is a devastating condition affecting the skin that appears to be triggered through an allergic reaction to medication such as Zithromax. There are many other medications linked to SJS as well. In the case of Zithromax, there have been reports of Zithromax side effects that include Stevens Johnson Syndrome, a condition characterized by Zithromax rash and blisters that often evolves into the loss of the upper layer of dermis. Skin is seen to slough away in sheets akin to a serious burn. SJS patients are often treated in burn units of hospitals, given the similarities.

Stevens Johnson Syndrome can be fatal. Those who have survived often emerge with permanent scarring and eye problems, including extreme light sensitivity.

Zithromax is already the most commonly prescribed antibiotic in the US for pneumonia, skin and throat infections. A growing health concern in North America - drug-resistant infections, or so-called “superbugs” - has never been fought with Zithromax as the latter was never shown to be effective against superbugs in standard lab tests.

But that could be changing, based on new research published in June that tested Zithromax (azithromycin) under conditions more closely resembling those of the human body.

According to The San Diego Tribune (The Tribune, 6/11/15), researchers at UC San Diego (UCSD) tested azithromycin against a collection of the newer class of superbugs known as Gram-negative rods; resistant strains of Pseudomonas aeruginosa, Klebsiella pneumoniae and Acinetobacter baumannii. Rather than standard lab tests, researchers introduced Zithromax to the superbugs in mammalian tissue cultures, which produce antibiotic chemicals naturally present in the human body. Researchers also tested the antibiotic in live mice. The treated mice experienced a 99 percent drop in multidrug-resistant A. baumannii pneumonia compared with untreated mice.

“[The study] comes on the heels of our working on similar questions with other drug-resistant pathogens like MRSA, where we saw some of the antibiotics that did not have activity in the classical testing actually worked very well when you combined them with the natural antibiotics from your immune system,” said Dr. Victor Nizet, a professor of pediatrics and pharmacy at UCSD, in comments published in The Tribune. Nizet led the study and served as senior author. Leo Lin, a colleague of Nizet’s at UCSD, was first author.

Colleagues in the medical community appear to be embracing the possibilities Zithromax has in fighting superbugs. “The data presented by Lin and colleagues is novel and interesting,” said Dr. James A. McKinnell, an assistant professor of medicine at UCLA’s David Geffen School of Medicine. “The results of the current study suggest the antibiotic azithromycin may play an important role in helping the immune system kill bacteria, particularly drug-resistant bacteria,” said McKinnell, in The Tribune.

Dale Boger, a prominent professor at The Scripps Research Institute who studies antibiotics, agreed the work was encouraging.

“This study reports exciting new observations that have the possibility of immediately impacting the treatment of life-threatening resistant bacterial infections using a well-established clinically used antibiotic,” Boger said, in comments published in The Tribune. “The authors of the work demonstrate that while traditional methods of testing antibiotics were not successful at identifying how successful azithromycin might be, the alternative methods the authors employed were.”

What does all this mean for Zithromax SJS?

Here’s the thing: according to a report released by the US Centers for Disease Control and Prevention (CDC) in 2013, at least 2 million Americans contract serious infections from superbugs. Further, there are 23,000 deaths each year attributed to superbug infection, with even more deaths resulting from indirect complications stemming from those infections.

Little wonder that the medical community is encouraged with this latest news about Zithromax. Even though Zithromax was never approved for fighting superbug infections by the US Food and Drug Administration (FDA), doctors have always had the medical and ethical authority to prescribe medications off-label to their patients for indications not supported by the FDA, provided the doctor feels his patient could benefit.

Will this new, off-label use of Zithromax increase the prevalence of Zithromax side effects and thus the chance for Zithromax rash that could be a precursor to Zithromax Stevens Johnson Syndrome?

Hence the potential for a perfect storm: an already oft-prescribed antibiotic is seen as a new weapon against the growing prevalence of drug-resistant superbugs. In fighting a superbug, patients could also be exposed to the potential for Zithromax SJS.

Pundits and commentators - while encouraged - are also sounding a cautionary note, suggesting that more research is needed. “Before these important basic science discoveries can be translated into routine clinical practice, significant translational research and comparative effectiveness studies need to be conducted,” McKinnell said.

“However, given the relative safety of azithromycin [Zithromax], some doctors may consider using azithromycin in some patients.”

The stampede has yet to begin. But the barn door has been opened.

Nizet’s and Lin’s research was funded in part by the National Institutes of Health. The study was published online June 10 in EBioMedicine.