Sun poisoning vs sunburn

"Sun poisoning" is not a medical diagnosis. It is the common name for severe sunburn accompanied by systemic symptoms — extensive blistering, fever, chills, nausea, dizziness, headache or confusion. Ordinary sunburn is red, sore and warm and settles with home care over several days. Systemic symptoms, extensive blistering, or any confusion or fainting mean contact a clinician rather than managing it at home.

This page is general information and is not a substitute for medical advice. If you are worried about a burn, call someone qualified rather than reading further.

Telling them apart

When to seek medical help

Contact a clinician if any of the following apply:

• Blistering over a large area, or blistering on the face.
• Fever or chills alongside the burn.
• Nausea, vomiting or severe headache.
• Dizziness, confusion or fainting — seek help immediately.
• Signs of infection in blistered skin: increasing pain, pus, red streaking, or a fever appearing days later.
• Any significant sunburn in an infant under one year. The threshold for calling is deliberately lower.
• Severe pain that is not manageable.
• Signs of dehydration — very dark urine, no urination, extreme thirst, lethargy.

Home care for ordinary sunburn

1. Get out of the sun, and stay out of it until the burn has fully settled.
2. Cool the skin with cool (not cold) compresses or a cool shower. No ice directly on skin.
3. Moisturize with a plain, fragrance-free emollient while the skin is still damp. Aloe is fine and unglamorous plain moisturizer works just as well.
4. Drink fluids. Burned skin loses water, and dehydration is a real secondary risk.
5. Over-the-counter pain relief as appropriate for you, following the package directions.
6. Leave blisters alone. Breaking them opens a route for infection. Cover loosely if they may rub.
7. Wear loose clothing over the area, and keep it covered when you go outside.

What not to do

• Do not apply petroleum jelly or thick occlusive ointments to a fresh burn — they trap heat.
• Do not use products containing benzocaine or lidocaine unless a clinician has recommended them; they can cause reactions on damaged skin.
• Do not pop blisters.
• Do not put butter, vinegar, toothpaste or oil on it. All are folk remedies and all make things worse.
• Do not go back out in the sun until it has fully healed. Burned skin is more vulnerable, not less.

Polymorphic light eruption is a different thing

Some people use "sun poisoning" to describe an itchy rash of small bumps or blisters appearing hours to days after sun exposure, typically on the chest, arms or neck and typically at the start of a sunny season. That is usually polymorphic light eruption, a sun-induced rash rather than a burn.

It tends to recur each year and to settle as skin acclimatizes over a season. It is worth having diagnosed rather than self-identified, because several other photosensitivity conditions and some medication reactions look similar — and a dermatologist can tell them apart.

Medication can make you burn faster

A number of common medications increase photosensitivity, including some antibiotics, retinoids, certain diuretics and some anti-inflammatory drugs. If a burn happened far faster than you expected, medication is a plausible explanation and a good reason to ask a pharmacist or clinician.

Why any of this matters after it heals

Sunburn is DNA damage, and it accumulates. The Skin Cancer Foundation notes that a history of blistering sunburns substantially raises the risk of melanoma later in life, and the risk is particularly associated with burns in childhood.

That is the real argument for everything else on this site. How much sunscreen to apply, a UPF shirt and shade are all cheaper than a burn, and considerably cheaper than what a burn contributes to.