### What is Phytophotodermatitis? Phytophotodermatitis (PPD) is an inflammatory skin reaction that occurs when certain chemicals in plants or fruits come into contact with your skin and are then exposed to sunlight. This reaction is caused by a substance called psoralen, which is found in many plants. When your skin absorbs psoralen and is then exposed to UVA light from the sun, it triggers a painful skin reaction. ### Common Causes PPD is most common in the spring and summer when psoralen concentrations in plants are highest and people spend more time outdoors. Common plants that can cause PPD include citrus fruits like lemons and limes. ### Symptoms Symptoms usually appear 24 to 48 hours after exposure and can include painful, blistered rashes. The skin changes can peak 3 to 4 days later and may take several weeks to heal. The rash is typically not itchy but can become itchy as it heals and the damaged skin begins to peel off. ### Diagnosis A dermatologist can diagnose PPD by examining your skin and taking a medical history. If you know you've been in contact with plants or produce containing psoralen, let them know. ### Treatment There is no cure for PPD, but symptoms can be managed. Treatments include anti-inflammatory creams, pain relievers, and in severe cases, topical steroids. If you develop complications like secondary infections, you should see a dermatologist for additional treatment. ### Prevention The best way to prevent PPD is to avoid direct skin contact with plants and produce that contain psoralen when your skin is exposed to sunlight. Wear protective clothing and wash your skin immediately if you come into contact with these plants. ### When to See a Doctor If over-the-counter treatments do not help or if you have a severe skin reaction, see a dermatologist. They can prescribe stronger medications to help your skin heal.