Sun Sensitivity: What Causes It and Which Medications Make It Worse

When your skin reacts badly to sunlight—not just with a mild tan but with rashes, burns, or blisters—you’re dealing with sun sensitivity, a condition where the skin overreacts to ultraviolet (UV) light, often due to medications, medical conditions, or genetics. Also known as photosensitivity, it’s not just bad luck in the sun—it’s often a side effect of something you’re taking daily. Many people assume sunburns are just from too much time outdoors, but if you’re using common drugs like antibiotics, diuretics, or even some acne treatments, your skin could be far more vulnerable than you realize.

Drugs like tetracycline, a widely prescribed antibiotic that increases skin reactivity to UV rays, are classic triggers. So are indapamide, a diuretic used for high blood pressure and heart failure that can cause severe sun reactions, and even some antidepressants and NSAIDs. These aren’t rare cases—studies show over 100 medications can cause this reaction, and many patients don’t even know they’re at risk. The result? A painful rash after a short walk, or worse, blistering skin after a day at the beach. It’s not just about sunscreen. It’s about knowing what’s in your medicine cabinet.

If you’re on long-term meds—for diabetes, heart issues, arthritis, or mental health—you’re more likely to be affected. People with autoimmune diseases like lupus often deal with sun sensitivity too, but even healthy adults on a simple course of Bactrim or doxycycline can suddenly burn through their clothes. The key is recognizing the pattern: if you notice unusual skin reactions after starting a new drug, and they get worse in sunlight, it’s not a coincidence. Talk to your doctor. Check your Medication Guide. And don’t assume it’s just a "bad sunburn."

Below, you’ll find real-world guides that break down exactly which drugs are linked to sun sensitivity, how to spot the signs early, and what steps to take if you’re already affected. From comparing antibiotic risks to understanding how immune suppressants change your skin’s defense, these posts give you the facts—not guesses—so you can protect yourself without avoiding the outdoors entirely.