What should you know about sudden sun sensitivity?

Photosensitivity may look like an exaggerated sunburn, an itchy rash, blisters, or darker patches in exposed areas. It can appear after starting or changing a medicine, applying a new skincare or fragrance product, or using a treatment that makes skin more reactive to ultraviolet light. The reaction may affect the face, neck, arms, hands, or other uncovered skin, sometimes with a clear clothing line. A new rash after a medicine can be a presentation of a drug rash, but the appearance alone cannot identify the trigger. Note the timing, exposed areas, products, medicines, and how quickly the skin changes.

Move out of direct sun, cover exposed skin with closely woven clothing and a hat, and use shade. Stop any newly introduced non-essential skincare or fragrance product while seeking advice. Do not stop a prescribed medicine without speaking with the prescriber; ask whether an alternative or different timing is appropriate. Cool compresses and a gentle fragrance-free moisturiser may soothe mild irritation. Read more about [Sun Sensitivity](/symptoms/sun-sensitivity/) and [Drug Rash](/conditions/drug-eruption/).

Seek urgent help for facial swelling, trouble breathing, widespread blistering, skin peeling, severe pain, fever, mouth or eye sores, or feeling faint. Arrange prompt medical review if the rash keeps returning, spreads beyond sun-exposed skin, or follows a new medicine. A clinician may need to review every medicine and product, not only the most recently added one.

Could a medicine or skincare product be causing this reaction? How long should I protect the skin from ultraviolet light? Which symptoms would require urgent care, and should my medicines be reviewed?