Laptop Safety Warnings Highlight a Boy’s Net-Like Stomach Rash

A boy in England developed a lace-like rash on his stomach after resting a laptop on his bare abdomen for as long as eight hours a day, often while it was charging. The case was reported earlier this month by MedicalDaily. What has received less attention is that laptop manufacturers already caution against this kind of use.

HP’s user guide is direct. “To reduce the possibility of heat-related injuries or of overheating the computer, do not place the computer directly on your lap or obstruct the computer air vents,” it says in a guide on HP’s website. The same instructions also warn users not to let the AC adapter touch the skin while the device is operating.

A Rash That Led Doctors Down the Wrong Path

The case, published in BMJ Case Reports by Mara Znagoveanu and Edward Artley of University Hospitals of Leicester in England, involved a reddish-brown, net-like rash roughly 15 centimeters, or 6 inches, across. Because the boy had been shoved into a chair during play-fighting about a week earlier, doctors initially feared a liver injury. Blood tests and abdominal scans came back normal.

The explanation emerged from his daily routine. He was being home-schooled and would use his laptop on his bare stomach for hours at a time. Doctors diagnosed erythema ab igne, more commonly known as toasted skin syndrome. After he stopped placing the laptop on his body, the rash gradually faded and had disappeared by a follow-up visit months later.

In a BMJ Group press release, the authors described device use, especially during home schooling, as “an under-recognised cause of erythema ab igne in paediatric populations.”

What the Safety Guidance Says

Apple offers similar advice in its MacBook Pro safety information. “Use common sense to avoid situations where your skin is in prolonged contact with a device or its power adapter when it’s operating or plugged into a power source,” it says.

The guide also states, “If your MacBook Pro is on your lap and gets uncomfortably warm, remove it from your lap and place it on a stable, well-ventilated work surface.” It further advises users not to sleep with a device or power adapter while it is plugged in, and not to put it “under a blanket, pillow, or your body” when connected to power.

The charging detail is notable. The boy often used his laptop while it was plugged in, which is exactly the situation both companies flag.

In practice, the word “laptop” describes how many people use these computers more than how some makers recommend using them. For children, those warnings are buried in manuals that adults may rarely open, much less read aloud.

Apple also advises people to “take special care if you have a physical condition that affects your ability to detect heat against the body.” Children are not specifically named, but they may be focused on schoolwork or games and slow to notice that a device is warming up or that their skin is changing.

Heat That Does Not Feel Like a Burn

Toasted skin syndrome does not require an actual burn. According to DermNet, a dermatology reference, repeated exposure to heat that is too mild to cause a direct burn can produce “a mild and transient red rash resembling lacework or a fishing net.” With ongoing exposure, it can progress to more pronounced redness, darker or lighter patches, and thinning skin.

Before central heating became common, the condition was often seen in older people who sat near open fires or space heaters. It also appears in workers exposed to heat on the job, including bakers, chefs, and silversmiths. Modern sources include hot water bottles, heating pads, car heaters, heated furniture, and electronic devices.

The main treatment is removing the heat source. DermNet notes that mild cases usually clear on their own over several months, although pigment changes can last for years. In rare severe or long-lasting cases, a form of skin cancer called squamous cell carcinoma may develop, so a sore that will not heal or a growing lump in the area should be biopsied.

A 2025 case-control analysis of the National Institutes of Health’s All of Us database, published in Baylor University Medical Center Proceedings, found an association between erythema ab igne diagnoses and higher odds of several skin cancers. The study showed a link in health records, not proof that the rash itself causes cancer.

Simple Steps That Can Prevent It

Based on the manufacturers’ own advice, laptops should be used on a desk or table, or on a lap desk or tray that keeps the machine off the skin. Devices that are charging should not be used against bare skin, in bed, or under blankets.

Parents can also look for a mottled, net-like pattern on the thighs or abdomen, especially in children who spend long stretches on devices. Since the rash can resemble bruising or other conditions, telling a clinician about device habits may help avoid unnecessary tests.

Toasted skin syndrome is usually not dangerous, and it often fades once heat exposure stops. Anyone with a persistent rash, changes in skin texture, a sore that does not heal, or a new growth in the affected area should seek medical attention.

Key Questions Answered

What is toasted skin syndrome?

Also called erythema ab igne, it is a net-like skin discoloration caused by repeated exposure to heat that is not hot enough to cause a burn.

How did the boy develop it?

He used a laptop on his bare abdomen for up to eight hours a day during homeschooling, often while it was charging.

Do laptop makers warn about this?

Yes. An HP user guide says not to place a computer directly on your lap, and Apple advises avoiding prolonged skin contact with a device that is operating or plugged in.

Does the rash go away?

Mild cases usually fade over several months after the heat source is removed, though pigment changes can remain for years.

Is it dangerous?

Usually not, but severe or long-standing cases can rarely lead to skin cancer, so persistent changes should be examined.

How can families prevent it?

Keep laptops on a desk, table, or lap tray, and avoid using charging devices directly against the skin, in bed, or under blankets.