Photodermatitis is an abnormal skin response to ultraviolet (UV) rays, particularly sunlight. It can be acute or chronic. UV rays are classified by wavelength and the greater the wavelength, the greater the risk of developing photodermatitis. UVB rays range from 290 to 320 nm and may cause sunburn, tanning, aging, or cancer-causing changes to the skin. UVA rays range from 320 to 400 nm and may cause reactions to light even through window glass. Ninety percent of the UV radiation from sunlight comes from UVA rays, 10% from UVB. Photoreactions from UV rays depend upon the amount of light reaching the earth. This is influenced by the season or time of year, latitude, thickness of the ozone layer, and topography.

Photodermatitis signs and Symptoms

What Causes It?

Certain chemical agents and drugs may predispose an individual to sunburn, an eczema-like reaction, or hives in reaction to UV rays. In the United States alone, there are more than 115 chemical agents and drugs that are ingested or applied to the skin that may elicit photodermatitis. The reaction may be related to an allergy or it may be a direct toxic effect from the substance. Below are examples of agents or circumstances that may trigger one or the other type of reaction:

Direct toxic effect: Allergic reactions: Photodermatitis may also result from some immune-related disorders such as systemic lupus erythematosus (SLE) or certain states of nutrient deficiencies, including pellagra, which is caused by niacin (vitamin B3) deficiency.

Who's Most At Risk?

What to Expect at Your Provider's Office

A physical exam and a detailed history of exposure to sensitizers (see section entitled What Causes It?) and UV rays are important for diagnosis. A review of all body systems, including blood and urine tests, helps detect any related disease. Allergy tests may help identify substances that trigger or worsen the condition.

Photodermatitis Treatment


These measures may help prevent photodermatitis:

Treatment Plan

For blisters or weepy eruptions, apply cool, wet dressings. With certain types of photodermatitis, doctors may actually use phototherapy (controlled exposure to light for treatment purposes) to desensitize the skin or to help control symptoms.

Drug Therapies

For extremely sensitive patients, doctors may prescribe azathioprine to suppress the immune system. Short-term use of glucocorticoids may help control eruptions. For those who cannot be treated with phototherapy, doctors may prescribe hydroxychloroquine, thalidomide, beta-carotene, or nicotinamide (see section entitled Nutrition for details regarding the latter two). Note: Thalidomide causes severe birth defects and therefore should never be used by women who either are or wish to become pregnant.

Complementary and Alternative Therapies

Particular nutritional deficiencies can contribute to photosensitivity. Pellagra, for example, is caused by a niacin deficiency. Recent research results suggest that antioxidant nutrients, including beta-carotene, may help lessen the severity of photodermatitis. Herbs Similar to photosensitizing medications, certain herbs can trigger photodermatitis; such herbs include St. John's wort (Hypericum perforatum), angelica seed or root (Angelica archangelica), celery stems (Apium graveolens), rue (Rutae folium), and lime oil/peel ( Citrus aurantifolia).

While scientific studies of homeopathy specifically addressing photodermatitis have not been conducted to date, individual reports suggest that homeopathic remedies may be a useful adjunct for the prevention and treatment of photodermatitis. An experienced homeopath considers each individual case and may recommend treatments tailored to address both the underlying condition and any current symptoms.

Prognosis/Possible Complications

Most photosensitivity reactions go away on their own and cause no permanent harm. However, symptoms can be severe when associated with a systemic disorder or when the exposure has been severe. Some photosensitivity reactions can continue for years after exposure ends.

Complications may include:

Following Up

Patients who need steroids to treat photosensitivity reactions must be monitored closely. In addition, anyone with a history of photodermatitis or photoreactivity should keep track of the frequency and duration of symptoms. This information can help determine the cause and appropriate treatment.


Abramowitz AI, Resnik KS, Cohen KR. Margarita photodermatitis [letter]. N Engl J Med. 1993;328(12):891.

Adamski H, Benkalfate L, Delaval Y, et al. Photodermatitis from non-steroidal anti-inflammatory drugs. Contact Dermatitis. 1998;38(3):171-174.

American Academy of Pediatrics. Ultraviolet light: a hazard to children. Pediatrics. 1999;104(2):328-333.

Benzodiazepines. NMIHI. Accessed at on November 8, 2018.

Blumenthal M, ed. The Complete German Commission E Monographs: Therapeutic Guide to Herbal Medicines.Boston, Mass: Integrative Medicine Communications; 1998:35-36; 214-215; 245-249.

Callen JP. Photodermatitis in a 6-year-old child. Arthritis Rheum. 1993;36(10):1483-1485.

Darr D, Dunston S, Faust H, Pinnell S. Effectiveness of antioxidants (vitamin C and E) with and without sunscreens as topical photoprotectants. Acta Derm Venereol (Stockh). 1996;76(4):264-268.

Durán MM, Ordoñez CP, Prieto JC, Bernal J. Treatment of actinic prurigo in Chimila Indians. Int J Dermatol. 1996;35(6):413-416.

Eberlein-König B, Placzek M, Przybilla B. Protective effect against sunburn of combined systemic ascorbic acid (vitamin C) and d-alpha-tocopherol (vitamin E). J Am Acad Dermatol. 1998;38(1):45-48.

Effects of Early Sun Exposure. American Academy of Family Physicians Accessed at on September 9, 2018.

Enta T. Dermacase. Contact photodermatitis. Can Fam Physician. 1995;41:577, 586-587.

Enta T. Dermacase. Photodermatitis reaction to chlorothiazide. Can Fam Physician. 1994;40:1269, 1276.

Fernandez de Corres L, Diez JM, Audicana M. Photodermatitis from plant derivatives in topical and oral medicaments. Contact Dermatitis. 1996;35(3):184-185.

Freedberg IM, Eisen AZ, Wolff K. Fitzpatrick's Dermatology in General Medicine. Vol. 1. 5th ed. New York, NY: McGraw-Hill; 1996:1573-1586.

Fuchs J, Kern H. Modulation of UV-light-induced skin inflammation by D-alpha-tocopherol and L-ascorbic acid: a clinical study using solar simulated radiation. Free Radic Biol Med. 1998;25(9):1006-1012.

Garmyn M, Ribaya-Mercado JD, Russell RM, Bhawan J, Gilchrest BA. Effect of beta-carotene supplementation on the human sunburn reaction. Exp Dermatol. 1995;4(2):104-111.

Goldman L, Bennett JC. Cecil Textbook of Medicine. 21st ed. Philadelphia, Pa: W.B. Saunders; 2000:2295-2296.

Hadshiew I, Stäb F, Untiedt S, Bohnsack K, Rippke F, Hölzle E. Effects of topically applied antioxidants in experimentally provoked polymorphous light eruption. Dermatology. 1997;195(4):362-368.

Hanada K, Sawamura D, Nakano H, Hashimoto I. Possible role of 1,25-dihydroxyvitamin D3-induced metallothionein in photoprotection against UVB injury in mouse skin and cultured rat keratinocytes. J Dermatol Sci. 1995;9(3):203-208.

Kamat JP, Devasagayam TP. Methylene blue plus light-induced lipid peroxidation in rat liver microsomes: inhibition by nicotinamide (vitamin B3) and other antioxidants. Chem Biol Interact. 1996;99(1-3):1-16.

Katiyar SK, Matsui MS, Elmets CA, Mukhtar H. Polyphenolic antioxidant (-)-epigallocatechin-3-gallate from green tea reduces UVB-induced inflammatory responses and infiltration of leukocytes in human skin. Photochem Photobiol. 1999;69(2):148-153.

Leroy D, Dompmartin A, Szczurko C, Michel M, Louvet S. Photodermatitis from ketoprofen with cross-reactivity to fenofibrate and benzophenones. Photodermatol Photoimmunol Photomed. 1997;13(3):93-97.

Leung AY, Foster S. Encyclopedia of Common Natural Ingredients Used in Food, Drugs and Cosmetics. 2nd ed. New York, NY: Wiley and Sons; 1996.

Magaña-Garcia M, Magaña M. Actinic prurigo. The possible etiologic role of an amino acid in the diet. Med Hypotheses. 1993;41(1):52-54.

Moschella SL, Hurley HJ. Dermatology. 3rd ed. Philadelphia, Pa: W.B. Saunders; 1992:507-530.

Montelukast. NMIHI. Accessed at on September 1, 2018.

Murata Y, Kumano K, Ueda T, Araki N, Nakamura T, Tani M. Photosensitive dermatitis caused by pyridoxine hydrochloride. J Am Acad Dermatol.1998;39(2 pt 2):314-317.

NSAIDs. NMIHI. Accessed at on November 8, 2018.

Neumann R, Rappold E, Pohl-Markl H. Treatment of polymorphous light eruption with nicotinamide: a pilot study. Br J Dermatol. 1986;115(1):77-80.

Newall CA, Anderson LA, Philpson JD. Herbal Medicines: A Guide for Health-care Professionals. London: The Pharmaceutical Press; 1996.

Pigatto PD, Legori A, Bigardi AS, et al. Multicenter study of allergic contact photodermatitis: epidemiological aspects. Am J Contact Dermat. 1996;7(3):158-163.

Quinones D, Sanchez I, Alonso S, et al. Photodermatitis from tetrazepam. Contact Dermatitis. 1998;39(2):84.

Rhodes LE, Durham BH, Fraser WD, Friedmann PS. Dietary fish oil reduces basal and ultraviolet B-generated PGE2 levels in skin and increases the threshold to provocation of polymorphic light eruption. J Invest Dermatol. 1995;105(4):532-535.

Rhodes LE, White SI. Dietary fish oil as a photoprotective agent in hydroa vacciniforme. Br J Dermatol. 1998;138(1):173-178.

Ross JB, Moss MA. Relief of the photosensitivity of erythropoietic protoporphyria by pyridoxine. J Am Acad Dermatol. 1990;22(2 pt 2):340-342.

Vardenafil. NMIHI. Accessed at on September 15, 2018.

Scholzen TE, Brzoska T, Kalden DH, et al. Effect of ultraviolet light on the release of neuropeptides and neuroendocrine hormones in the skin: mediators of photodermatitis and cutaneous inflammation. J Invest Dermatol Symp Proc. 1999;4(1):55-60.

Stahl W, Heinrich U, Jungmann H, Sies H, Tronnier H. Carotenoids and carotenoids plus vitamin E protect against ultraviolet light-induced erythema in humans. Am J Clin Nutr. 2000;71(3):795-798.

Sun Exposure. MedlinePlus. Accessed at on September 9, 2018.

Sunburn treatment: Do I need medical attention? MFMER. Accessed at on September 9, 2018.

Tanaka M, Niizeki H, Shimizu S, Miyakawa S. Photoallergic drug eruption due to pyridoxine hydrochloride. J Dermatol. 1996;23(10):708-709.

Tricyclic antidepressants. NMIHI. Accessed at on November 8, 2018.

Tierney LM, McPhee SJ, Papadakis MA. Current Medical Diagnosis and Treatment 2000. New York, NY: Lange Medical Books/McGraw-Hill; 2000:177-178.