What is photosensitivity?

Photosensitivity is an extreme sensitivity to ultraviolet (UV) rays from the sun and other light sources. Most people are at risk of developing sunburn during long exposure to sunlight.

Exposure to UV rays can also lead to skin damage and skin cancer. People who are photosensitive may develop skin rashes or burns, even after only limited exposure to the sun.

Some chemicals contribute to sensitivity to the sun. These can cause two different types of photosensitive reactions: phototoxic and photoallergic.


Phototoxic reactions are caused when a new chemical in your body interacts with UV rays from the sun. Medications like doxycycline and tetracycline, for example, are the most common cause of this type of reaction.

The result is a skin rash that looks like a severe sunburn, which usually develops within 24 hours of exposure to the sun.


Photoallergic reactions can develop as a side effect of some medications. They can also arise from chemicals found in beauty products and sunscreen.

These types of reactions to the sun tend to take a few days for a rash to develop after sun exposure.

Symptoms of photosensitivity vary from mild to severe. The most common symptom is an exaggerated skin rash or sunburn. Rashes may or may not cause itching. In some cases, a sunburn can be so severe that blistering develops. Weeping of your skin and peeling can also occur in severe cases.

The amount of sun exposure required for a reaction varies greatly. For some people, very little sun exposure can cause a rash or burn, while for others, prolonged exposure will bring about a reaction.

Photosensitivity is a common side effect of various medications, including:

  • certain antibiotics
  • chemotherapy drugs
  • diuretics

Some medical conditions can also cause photosensitivity. These include:

Lupus erythematous

Lupus is a connective tissue disease. Red patches, lumps, and purple spots can develop on areas of your skin exposed to the sun.

Polymorphous light eruption

People with this condition can develop an itchy rash when they are exposed to the sun. As sun exposure continues and UV tolerance increases, symptoms generally appear less often. Women are two to three times more likely than men to develop this condition.

Actinic prurigo

People with this condition may develop red bumps after sun exposure, which can turn into scaly patches. This disorder can occur year-round, even in winter when sun exposure is less likely.

Your doctor will need a complete review of your medical history and the medications you are currently taking to make a proper diagnosis. They will pay attention to the development and patterns of rashes in relation to your sun exposure. In some cases, your doctor may recommend a skin biopsy.

When a skin reaction has already developed, treatments may reduce discomfort and skin inflammation. Over-the-counter pain medications can relieve pain and corticosteroid cream may be prescribed to decrease inflammation.

Some chemicals can cause photosensitivity and should be avoided. These chemicals can be found in some medications and products, such as some forms of chemotherapy. However, sometimes it’s not possible to avoid taking these medications.

The best way to prevent symptoms of photosensitivity is to limit the amount of time you spend in the sun. People who are photosensitive should always use sunscreen when outside.

Covering and protecting your skin may also help prevent a reaction. People who are photosensitive can reduce symptoms by wearing hats, sunglasses, and shirts with long sleeves when outside.

These simple tips can help protect your skin and help you live a healthy life.