Top 5 Medications That Can Make You More Sensitive to the Sun

Whether you're on a cholesterol-reducing medication or applying an antifungal cream for athlete's foot, sunburns and scarring may not cross your mind. However, these drugs, among others, can trigger chemically-induced photosensitivity, so it's crucial to take precautions such as avoiding direct sun and applying sunscreen regularly.

Drug-induced photosensitivity is a common side effect of not just medications but also herbal remedies, sunscreens, and perfumes. This condition can manifest in two forms. The most frequent is phototoxicity, where UV exposure causes drugs to generate free radicals, leading to severe sunburns in areas directly exposed to sunlight. The second form, photoallergy, occurs when sunlight converts drugs into allergens called haptens, causing allergic skin reactions such as rashes or hives. Unlike phototoxicity, photoallergy can affect even areas of skin not exposed to the sun.

Before using any medication, whether prescription or over-the-counter, it's essential to carefully read the label and consult with your doctor about any potential for photosensitivity. Here are five more medications that may cause a photosensitive reaction.

5. Coal Tar

Coal tar is a thick, dark substance extracted from wood and coal. It's commonly used in over-the-counter treatments for conditions like psoriasis, seborrheic dermatitis (dandruff), and eczema. Thanks to its salicylic acid content, coal tar is effective for treating these skin issues. However, it also has phototoxic properties and can cause further skin damage when exposed to sunlight.

Coal tar, often found in topical treatments or as an active ingredient in dandruff shampoos, remains effective for about 24 hours [source: NPF]. However, it is advised that patients avoid direct sunlight on treated skin or scalp (if using medicated shampoo) for up to 72 hours after application [source: Mayo Clinic].

Research indicates that using sunscreen can help mitigate the phototoxic effects of coal tar [source: Diette et al].

4. Antidepressants

Several antidepressants are effective in reducing symptoms of depression, but they also come with the side effect of photosensitivity. While skin reactions are a well-known side effect of psychotropic medications, the exact cause of photosensitivity in antidepressants remains unclear to the medical community [source: Milionis et al.]. The variety of antidepressants is vast, and despite their different mechanisms of action, they all share this common photosensitive side effect. Medications like fluoxetine (a selective serotonin reuptake inhibitor), amitriptyline (a tricyclic), and even the herbal remedy St. John's Wort are known to cause photosensitivity.

Antidepressants have been associated with various photosensitive reactions, such as hives, sunburns, and rashes [source: Milionis]. In rare instances, some phototoxic reactions can lead to pigment changes in the skin, resulting in a bluish-gray appearance [source: Zhang]. Typically, these symptoms subside after the medication is discontinued.

3. Antibiotics

Two major classes of antibiotics are known to cause photosensitivity in patients, leading to phototoxic side effects. Tetracyclines, prescribed for bacterial infections like acne, typhus, chlamydia, and conjunctivitis, as well as fluoroquinolones, used for severe infections like MRSA, strep throat, and mononucleosis, can both trigger phototoxic reactions.

Due to their phototoxic properties, both tetracyclines and fluoroquinolones absorb sunlight and produce free radicals, which damage skin cells and tissues. This typically results in severe sunburn. Tetracyclines can also cause two additional phototoxic conditions. They may lead to pseudoporphyria, which causes painful blisters and open sores, potentially leaving behind pigmented spots on the skin. Another possible reaction is a lichenoid reaction, where tiny red bumps appear on the skin. To prevent these issues, it is recommended to avoid direct sunlight while taking these antibiotics.

2. Non-steroidal Anti-inflammatory Drugs (NSAIDs)

Non-steroidal anti-inflammatory drugs (NSAIDs), which include widely available over-the-counter pain relievers such as ibuprofen (marketed as Advil and Motrin), ketoprofen (Orudis), naproxen (Aleve), and celecoxib (Celebrex), are commonly used. However, many people aren't aware that these drugs may cause photoallergic or phototoxic reactions in some users.

Ibuprofen, ketoprofen, and naproxen have all been known to trigger phototoxic reactions in users [source: Zhang]. Experiencing severe sunburn or other unusual skin reactions while taking these NSAIDs may be a sign of phototoxicity. Both ketoprofen and celecoxib can also cause photoallergic responses in individuals [source: Zhang]. As with all photoallergic reactions, symptoms like hives and rashes typically appear 24 to 72 hours after sun exposure, as it takes this amount of time for the body to react allergically.

1. Sulfonamides

Sulfonamides are a class of antibacterial medications commonly used either orally or topically, particularly for treating burns. They work by inhibiting the bacterial synthesis of folate, eventually depriving bacterial colonies of nutrients and halting the spread of infections [source: Merck].

However, sulfonamides can also cause photoallergic reactions. Photoallergies occur when the drug is converted into haptens, which then trigger an immune response in the body, leading to an allergic reaction that can affect areas of skin not directly exposed to sunlight.

Since sulfonamides absorb sunlight and convert it into haptens, users should avoid sun exposure while undergoing treatment. The resulting photoallergic reaction typically manifests as a rash, intense itching (pruritus) that doesn't improve with scratching, and blisters [source: Merck].