Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis: Recognizing Medication-Related Skin Emergencies

Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) aren’t just rare skin rashes. They’re life-threatening emergencies that can turn a routine medication into a killer. If you or someone you know develops a sudden, painful rash with blisters or peeling skin after starting a new drug, time is everything. Waiting even a day can mean the difference between survival and death.

What You’re Seeing: Skin Falling Off

SJS and TEN are two ends of the same dangerous spectrum. They both start with something that feels like the flu-fever, sore throat, fatigue-then suddenly shift into something terrifying. Within a few days, a red or purple rash spreads across the body. Blisters form. The top layer of skin begins to die and peel away, sometimes in sheets. It looks like a severe burn, but it’s not caused by heat. It’s caused by your own immune system attacking your skin and mucous membranes because of a medication.

The difference between SJS and TEN is how much skin is affected. If less than 10% of your body surface is involved, it’s classified as SJS. If more than 30% peels off, it’s TEN. Between 10% and 30%? That’s overlap syndrome. The more skin lost, the higher the risk of infection, organ failure, and death. In severe TEN, up to 100% of the skin can detach. This isn’t a rash you can treat with lotion. This is a medical crisis requiring intensive care.

Which Medications Trigger This?

Not every drug causes this. But certain ones carry a known, documented risk. The most common culprits include:

• Allopurinol - Used for gout, it’s one of the top triggers, especially in people with the HLA-B*58:01 gene variant.
• Lamotrigine - An epilepsy and bipolar medication. Rashes are common with this drug, but most aren’t serious. Still, the risk of SJS/TEN is real, especially if the dose is increased too fast or restarted after a break.
• Carbamazepine, phenytoin, phenobarbital - All anticonvulsants. Cross-reactivity is common. If you had a reaction to one, you’re at high risk for another.
• Nevirapine - An HIV medication linked to early-onset SJS, often within the first six weeks.
• Oxicam NSAIDs - Meloxicam and piroxicam. These are more dangerous than ibuprofen or naproxen when it comes to skin reactions.
• Sulfonamides - Like sulfamethoxazole (in Bactrim). These antibiotics have a long history of causing these reactions.

The key point? You don’t need to take these drugs for months. Reactions can happen within days, sometimes even after the first dose. And they can appear up to two weeks after you stop taking the drug. That’s why it’s dangerous to ignore a new rash just because you think you’re “off” the medication.

Who’s at Higher Risk?

Some people are more vulnerable. You’re at higher risk if:

• You’ve had SJS or TEN before - Re-exposure to the same drug or even a similar one can trigger it again, often faster and worse.
• You have HIV or are on chemotherapy - A weakened immune system makes reactions more likely and more severe.
• You’re taking sodium valproate with lamotrigine - This combo increases the chance of a dangerous rash.
• You’ve had a rash before with another epilepsy drug - Even if it was mild, it’s a red flag.
• You have a family member who had SJS/TEN - There’s a genetic link, especially with certain HLA gene types.

If you fall into any of these categories, talk to your doctor before starting any new medication. Ask: “Is this drug linked to SJS or TEN? Are there safer alternatives?”

What Happens After the Skin Peels Off?

Surviving SJS or TEN doesn’t mean you’re out of the woods. The damage goes far beyond the skin.

• Eyes - Up to half of survivors develop serious eye problems: dry eyes, scarring, eyelashes growing inward, corneal damage, and even blindness. This is why every survivor needs an ophthalmologist follow-up for at least a year.
• Mouth and throat - Blisters and sores make eating and swallowing painful. Long-term, you might develop strictures (narrowing) in the esophagus.
• Genitals - Women can develop vaginal scarring and stenosis. Men can get phimosis. These require ongoing care.
• Nails and hair - Nails may fall off or grow back deformed. Hair can thin out across the scalp. Most recover, but it takes months.
• Internal organs - The immune attack doesn’t stop at the skin. Lungs can fill with fluid. Kidneys and liver can fail. Blood clots and infections like sepsis are the leading causes of death.

The mortality rate? About 5% for SJS. For TEN, it jumps to over 30%. And those numbers don’t include the long-term disability many survivors face.

What Should You Do If You Suspect It?

If you’re on one of these high-risk drugs and you notice:

• A sudden fever and flu-like symptoms
• A spreading red or purple rash
• Blisters on your skin or inside your mouth, eyes, or genitals
• Skin that peels easily or feels like it’s sloughing off

Stop the medication immediately - but don’t just quit cold turkey without medical advice. Then, go to the emergency room right away. Don’t wait. Don’t call your doctor tomorrow. Don’t check online. Go now.

At the hospital, they’ll do a skin biopsy to confirm the diagnosis. Treatment is supportive - meaning they’ll treat the damage, not the cause. You’ll likely be moved to a burn unit or ICU. Fluids, pain control, infection prevention, and wound care are critical. Some hospitals try immune-modulating drugs like IVIG or corticosteroids, but evidence is mixed. The most proven intervention? Stopping the drug and getting expert care fast.

How to Prevent This

Prevention starts with awareness.

• If you’re prescribed lamotrigine, follow the slow titration schedule exactly. Never restart after a break without medical guidance.
• Don’t start new medications or try new foods during the first 8 weeks of high-risk drugs. This helps doctors tell if a rash is from the drug or something else.
• Know your family history. If someone close had SJS/TEN, tell your doctor before taking any new meds.
• Keep a list of all medications you’ve reacted to - and share it with every provider.
• Never take a drug you’ve had a reaction to before, even if it was “mild.”

Doctors are getting better at identifying genetic risks. For example, testing for the HLA-B*58:01 gene before giving allopurinol is now standard in some countries. Ask if testing is available for your medication.

Why This Matters More Than You Think

SJS and TEN are rare - maybe five cases per million users per week. But rarity doesn’t mean safety. These reactions are unpredictable. One person gets a rash and recovers. Another, with the same drug, same dose, same age, ends up in intensive care. There’s no sure way to know who’s at risk.

That’s why education is the best tool we have. Patients need to know the warning signs. Doctors need to know which drugs are dangerous. And everyone needs to understand: if your skin starts peeling after a new medication, it’s not a coincidence. It’s an emergency.

What Happens After Recovery?

Survivors need more than a hospital discharge. Long-term care is essential.

• Regular eye exams - every 3 to 6 months for at least a year.
• Dermatology follow-up for scarring, pigmentation changes, and nail health.
• Physical therapy if joints stiffened from scarring.
• Psychological support - many survivors develop PTSD from the trauma.
• A clear, written list of all drugs to avoid forever - including related compounds.

Many survivors carry a medical alert card or bracelet listing their triggers. It’s a small step that could save their life next time they’re in an emergency room.