Skin Care

Sun Poisoning vs Sunburn: When It's Serious

'Sun poisoning' is a lay term for severe sunburn plus systemic symptoms. The medical reality, what to watch for, and when to seek care.

'Sun poisoning' is not a formal medical diagnosis, but it captures a real phenomenon: severe sunburn accompanied by systemic symptoms like fever, chills, dehydration, and blistering. It's an emergency-medicine bucket that includes true polymorphous light eruption (PMLE), solar urticaria, and phototoxic drug reactions.

The severity spectrum

  • Mild sunburn: pink, warm, slightly tender, no blisters
  • Moderate sunburn: red, painful, tight-feeling, minor blistering
  • Severe ('sun poisoning'): extensive blistering, fever, chills, headache, nausea
  • PMLE / solar urticaria: itchy hive-like rash within hours of UV — an allergic-type response

Drugs that make you burn faster

Doxycycline, several diuretics (hydrochlorothiazide), retinoids (isotretinoin, tretinoin), some NSAIDs, and many antibiotics increase photosensitivity. A normal sun exposure on doxycycline can produce a severe burn — check the pharmacy insert for any new medication.

When to seek care

Fever above 102°F, signs of dehydration, extensive blistering, or confusion. Kids and older adults progress to heat illness faster and warrant a lower threshold.

Key takeaways

  • 'Sun poisoning' means severe burn plus systemic symptoms.
  • Photosensitizing drugs multiply burn risk.
  • Fever, dehydration, or extensive blistering: get medical care.

Related DermUV pages