Stevens Johnson syndrome and toxic epidermal necrolysis are two related and potentially deadly skin conditions. Though rare, both conditions are known side effects of hundreds of common medications, including the antibiotic Zithromax.

Zithromax is manufacturer Pfizer’s brand name for the antibiotic azithromycin. As is stated on Zithromax’s FDA-approved label, some patients have developed Stevens Johnson syndrome or toxic epidermal necrolysis in response to Zithromax treatment.

SJS and TEN are conditions that most often occur as a side effect of certain medications. Zithromax is one of over 200 such medications.

Cases of SJS that are triggered by antibiotics like Zithromax usually develop within one week of the beginning of the course. The first symptoms to manifest often mimic those of the flu or an upper respiratory infection: the patient may experience fever, cough, runny nose, or sore throat. There may also be some redness and soreness in the eyes and aches and pains in the genitals.

Shortly after that, the patient breaks out in a rash that starts on the trunk and spreads to the face and limbs. The areas of rash develop blisters that grow and merge, eventually forming large areas of skin that peel away, leaving the lower layer of skin exposed.

The main difference between the two conditions is in the area of skin affected. SJS affects less than 10% of body surface area, while TEN affects 30% or more. These conditions are now considered to be variants of each other. Both are severe and potentially fatal.

Rash and peeling skin are the trademark symptoms of SJS and TEN, but other symptoms can affect other parts of the body. Blisters may also form on the membranes that line the mouth, respiratory tract, digestive tract, or genitals. Internal blisters in the digestive and respiratory tracts may cause diarrhea and cough or respiratory distress.

They eyes can also develop painful and dangerous symptoms. Conjunctivitis may set in, leaving the eyes red, sore and purulent, and the patient may be at risk for damage to the corneas.

Complications in the conditions’ acute phase are what can make SJS or TEN fatal. The loss of the outer layer of skin results in severe dehydration and loss of nutrients. It also exposes the patient’s body to infection in the affected areas. Patients in this condition are at risk for shock and multiple organ failure.

Though death from SJS and TEN is rare, even after the condition resolves the patient may have to live with long-term or permanent complications. The skin can be left with areas of permanent scarring or change of color. Fingernails and toenails may fall out and fail to grow back. Most significantly, damage to the eyes during the acute phase may result in permanent blindness.

For patients, the costs of SJS and TEN can be substantial. Treatment of these conditions can require weeks of hospitalization, preventing the patient from earning income while medical expenses mount.

Settlements and jury awards arising out of cases of drug-induced SJS and TEN can be quite large. A Boston jury awarded $63 million to a plaintiff who was seven years old when she developed drug-induced toxic epidermal necrolysis.