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Non-melanoma skin cancer

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Potential side effects of photodynamic therapy for non-melanoma skin cancer

Side effects can occur with any type of treatment for non-melanoma cancer, but not everyone has them or experiences them in the same way. Side effects of photodynamic therapy (PDT) will depend mainly on the:

  • area of the body being treated
  • type of photosensitizer used
  • degree of sensitivity to light following treatment

Side effects can happen any time during, immediately after, or a few days or weeks after photodynamic therapy. Most side effects go away after photodynamic therapy is finished.

It is important to report side effects to the healthcare team. Doctors may also grade (measure) how severe certain side effects are. Sometimes photodynamic therapy needs to be adjusted if side effects are severe.


A burning sensation can occur after photodynamic therapy. The doctor may prescribe pain-relieving medications, if needed. Check with the doctor if pain does not go away or pain medications do not relieve the pain. At the end of a treatment, a steroid cream may be applied to the treated area to prevent or treat pain.

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Sensitivity to light

The photosensitizer used in PDT makes the skin and eyes sensitive to light (photosensitive) for 4–6 weeks or more after treatment. The length of photosensitivity is different for each person and depends on the photosensitizer used.

A photosensitive reaction may include swelling, rash or redness, similar to sunburn. It takes only a few minutes for a reaction to occur, so it is important to protect the eyes and skin from exposure to light.

  • Avoid direct sunlight or bright indoor light and use precautions to prevent photosensitivity reactions for at least 30 days.
  • Use shades or curtains on windows if the sun is bright.
  • Protect skin from the sun by covering up as much skin as possible when outdoors. Wear a wide-brimmed hat, clothing that covers the arms and legs and dark sunglasses. Apply sunscreen with a sun protection factor (SPF) of 30 or higher before going outside and limit time outdoors. Zinc oxide can be used to fully block out the sun, but it should be used along with other sun-protection measures.
  • Use a low-heat setting on hand-held hair dryers to avoid burns to the scalp. Do not use helmet-type hair dryers, such as those used in beauty salons.

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Blistering or scabbing may occur as the treated area heals, but this should disappear in time.

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Some swelling may occur, depending on the area treated. Swelling may cause problems, including chest or abdominal pain and difficulty breathing. Drugs, such as corticosteroidscorticosteroidsAny steroid hormone that acts as an anti-inflammatory by reducing swelling and lowering the body’s immune response (the immune system’s reaction to the presence of foreign substances)., may be used to reduce swelling.

Report chest pain, shortness of breath or abdominal pain to the doctor or healthcare team.

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Note: Other side effects may occur. For more detailed information on specific drugs, go to sources of drug information.


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