From the Guidelines
When taking pirfenidone, patients should take strict sun protection measures due to the medication's photosensitizing effects, as evidenced by a high risk of photosensitivity reaction, with a relative risk of 5.3 (1.46–19.24) and 264 more cases per 1,000 patients 1. To minimize the risk of sun sensitivity, patients should:
- Apply broad-spectrum sunscreen with SPF 50+ every 2 hours when outdoors
- Wear protective clothing, including long sleeves, pants, wide-brimmed hats, and sunglasses with UV protection
- Avoid direct sun exposure during peak hours (10 AM to 4 PM)
- Be aware that UV rays can penetrate clouds and windows
- Limit time outdoors, seek shade when possible, and avoid tanning beds completely These precautions are necessary because pirfenidone increases skin sensitivity to UV radiation, which can cause severe sunburn, rash, or blistering even with minimal sun exposure. Additionally, patients should moisturize regularly, use emollients or soap substitutes, and protect against excessive exposure to sunlight 1. It is also important to note that patients should not use sun tanning or tanning beds during or after treatment with pirfenidone, as it can affect the amount of UVA received during treatments and increase the risk of skin cancer 1. Patients should continue these precautions throughout treatment and report any skin reactions to their healthcare provider immediately.
From the FDA Drug Label
Advise patients to avoid or minimize exposure to sunlight (including sunlamps) during use of pirfenidone because of concern for photosensitivity reactions or rash. Instruct patients to use a sunblock and to wear clothing that protects against sun exposure. Instruct patients to report symptoms of photosensitivity reaction or rash to their physician. Temporary dosage reductions or discontinuations may be required [see Warnings and Precautions (5. 2)]. Avoid sunlight. Pirfenidone can make your skin sensitive to the sun and the light from sunlamps and tanning beds. You could get a severe sunburn
Patients taking pirfenidone should avoid or minimize exposure to sunlight due to the risk of photosensitivity reactions or rash. To protect themselves, patients should:
- Use a sunblock
- Wear clothing that protects against sun exposure
- Report any symptoms of photosensitivity reaction or rash to their physician Temporary dosage reductions or discontinuations may be required if such reactions occur 2, 2, 2.
From the Research
Precautions for Sun Sensitivity when Taking Pirfenidone
To minimize the risk of sun sensitivity when taking pirfenidone, the following precautions can be taken:
- Take pirfenidone during or after a meal 3, 4
- Avoid sun exposure, especially during peak hours 3, 4, 5
- Wear protective clothing, such as long-sleeved shirts and pants, and a wide-brimmed hat 3, 4
- Apply broad-spectrum sunscreen with high ultraviolet (UV) A and UVB protection 3, 4, 5
Clinical Manifestations of Photosensitivity
The clinical manifestations of photosensitivity caused by pirfenidone may include:
- Itching on body parts exposed to sunlight, such as the back of hands, face, neck, and limbs 3
- Erythema (redness of the skin) 3, 5
- Necrotic keratinocytes, lymphocytic inflammatory cell infiltrate, hyperkeratosis, and liquefaction degeneration (as seen in histopathological examination) 3
- Decreased minimum erythema dose (MED) of UV-B and UV-A 3, 5
Management of Photosensitivity
If photosensitivity occurs, the following management strategies can be employed: