AUTHOR INFORMATION

Section 1 of 11

Authored by James Foster, MD, MS, Consulting Staff, Department of Emergency Medicine, Palomar Pomerado Health

James Foster, MD, MS, is a member of the following medical societies: Alpha Omega Alpha, American College of Emergency Physicians, California Medical Association, and Phi Beta Kappa

Edited by James Li, MD, Assistant Professor, Division of Emergency Medicine, Harvard Medical School; Consulting Staff, Department of Emergency Medicine, Miles Memorial Hospital; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; A Antoine Kazzi, MD, Chief of Service, Department of Emergency Medicine, Medical Director of the Emergency Unit, American University of Beirut; John Halamka, MD, Chief Information Officer, CareGroup Healthcare System, Assistant Professor of Medicine, Department of Emergency Medicine, Beth Israel Deaconess Medical Center; Assistant Professor of Medicine, Harvard Medical School; and Charles V Pollack, Jr, MD, MA, FACEP, Professor, Department of Emergency Medicine, University of Pennsylvania College of Medicine; Chairman, Department of Emergency Medicine, Pennsylvania Hospital

Author's Email:	James Foster, MD, MS
Editor's Email:	James Li, MD

eMedicine Journal, October 24 2005, VOLUME 6, Number 10

INTRODUCTION

Section 2 of 11

Background: Sunburn is an acute cutaneous inflammatory reaction that follows excessive exposure of the skin to ultraviolet radiation (UVR). Long-term adverse health effects of repeated exposure to UVR are well described but are beyond the scope of this article.

Pathophysiology: Exposure to solar radiation has the beneficial effects of stimulating the cutaneous synthesis of vitamin D and providing radiant warmth. Unfortunately, when the skin is subjected to excessive radiation in the ultraviolet range (wavelength <400 nm), deleterious effects may occur. The most common is acute sunburn or solar erythema.

Solar erythema is associated with microscopic changes in the skin, detectable within 30 minutes of exposure to UVR. The most characteristic changes include formation of epidermal sunburn cells, damaged keratinocytes with hyaline cytoplasm, and pyknotic nuclei. Epidermal Langerhans cell and mast cell numbers may decrease, while the relative percentage of hypogranulated or degranulated cells may increase. Superficial blood vessels show endothelial swelling, perivenular edema, and a mixed perivascular infiltrate.

The precise biochemical pathways that lead to the sunburn reaction are not well understood but appear to involve multiple inflammatory mediators, including histamine, prostaglandins, and cytokines.

Less intense or shorter-duration exposure to UVR results in an increase in skin pigmentation, known as tanning, which provides some protection against further UVR-induced damage. The increased skin pigmentation occurs in 2 phases, (1) immediate pigment darkening, and (2) delayed tanning. Immediate pigment darkening occurs during exposure to UVR and results from alteration of existing melanin (oxidation, redistribution). It may fade rapidly or persist for several days. Delayed tanning results from increased synthesis of epidermal melanin and requires a longer period of time to become visible (24-72 h). With repeated exposure to UVR, the skin thickens, primarily due to epidermal hyperplasia with thickening of the stratum corneum.

Frequency:

• In the US: Incidence is highest in areas with the highest flux of solar radiation (ie, the southern United States).

• Internationally: Incidence is increased in regions that are closer to the equator, that are higher in altitude, and where individuals have lighter baseline skin pigmentation.

Mortality/Morbidity:

• Uncomplicated sunburn is associated with minimal short-term morbidity. Most cases resolve spontaneously with no significant sequelae.

• In rare cases, sunburn may be so severe and diffuse that it results in second-degree burns, dehydration, secondary infection, shock, or even death.

• Morbidity and mortality associated with long-term sun exposure is related primarily to the development of cutaneous neoplasms, including basal cell carcinoma, squamous cell carcinoma, and malignant melanoma.

Race: Lighter-skinned individuals are affected more frequently and severely. Skin types may be divided into 6 categories, based on an individual’s tendency to tan and/or burn (see Table 1).

Table 1. Skin Phototypes

Skin Phototype	Description	Typical Features	MED	Minimum SPF
I	Always burns, never tans	White skin, blue/hazel eyes, blond/red hair	15-30 mJ/cm2	>15
II	Always burns, tans minimally	Fair skin, blue eyes	25-40 mJ/cm2	>15
III	Burns minimally, tans slowly	Darker Caucasian skin	30-50 mJ/cm2	10-15
IV	Burns minimally, tans well	Light brown skin, Mediterranean	40-60 mJ/cm2	6-10
V	Rarely burns, tans profusely/darkly	Brown skin, Middle Eastern, Latin American	60-90 mJ/cm2	4-6
VI	Never burns, always tans, deeply pigmented	Dark brown or black skin	90-150 mJ/cm2	None

Age: Most people get the majority of their sun exposure when young, making sunburn more common in children and young adults. Some elderly individuals have a blunted sunburn response.

CLINICAL

Section 3 of 11

History:

• Recent sun exposure or outdoor activity; outdoor occupations or hobbies; use of indoor tanning equipment

• Erythema develops after 2-6 hours and peaks at 12-24 hours.

• Pain

• Possible fever, chills, malaise, nausea, or vomiting in severe cases

• Blistering

• Erythema that resolves over 4-7 days, usually with skin scaling and peeling

• Assess for exposure to photosensitizing drugs.

Physical:

• Patients at highest risk typically have fair skin, blue eyes, and red or blond hair.

• Immediate or early erythema occurs during UVR exposure and fades within 30 minutes.

• The acute inflammatory response is greatest 20-24 hours after exposure.

• Erythema

• Warmth

• Tenderness

• Edema

• Blistering (severe cases)

• Fever can present in severe cases.

• Most exposure is limited to sun-exposed areas of the body; however, significant transmission of UVR may occur through some clothing, resulting in sunburn on clothed skin.

• Delayed scaling and desquamation occurs 4-7 days after exposure.

Causes:

• The electromagnetic spectrum can be divided according to wavelength into ultraviolet ( <400 nm), visible (400-760 nm), and infrared (>760 nm).

• Sunburn is caused by excessive exposure of the skin to UVR.

• The ultraviolet spectrum can be divided into ultraviolet A (UV-A), 320-400 nm; ultraviolet B (UV-B), 290-320 nm; and ultraviolet C (UV-C), 200-290 nm.

• Solar UVR of wavelengths shorter than 290 nm is filtered out or absorbed in the outer atmosphere and is not encountered at sea level.

• UV-B radiation is much more potent at inducing erythema than UV-A and is, therefore, the principal cause of sunburn (about 85%).

• However, UV-A comprises the majority of UVR reaching the surface of the earth (about 90% at midday) and, therefore, accounts for a significant percentage of the immediate and long-term cutaneous effects of UVR.

• The minimal single dose of UVR (energy per unit area) required to produce erythema at an exposed site is known as the minimal erythema dose (MED). Moderate-to-severe sunburn occurs at 3-8 MEDs.

• Multiple factors influence UVR-induced erythema.

• Wavelength: UV-B is more erythemogenic than UV-A. Multiple wavelengths may result in an additive effect.

• Skin pigmentation: Compared with white-skinned individuals, moderately pigmented races require 3-5 times more UVR exposure to cause erythema; blacks require up to 30 times more. Facultative (induced) tanning increases MEDs by only 2-3 times.

• Skin thickness

• Hydration: UVR penetrates moist skin more effectively than dry skin.

• Anatomic site: MEDs are greater on the limbs than on the face, neck, and trunk.

• Environmental reflection: Radiation is 80% reflected by snow and ice, compared to 20% by sand.

• Altitude: UVR increases 4% for every 300-m (1000-ft) increase in elevation.

• Latitude: Exposure is greater at lower latitudes.

• Time of day: 65% of UVR reaches the earth between 10 am and 2 pm.

DIFFERENTIALS

Section 4 of 11

Burns, Chemical
Burns, Thermal
Cellulitis
Dermatitis, Atopic
Dermatitis, Contact
Dermatitis, Exfoliative
Heat Exhaustion and Heatstroke
Systemic Lupus Erythematosus

WORKUP

Section 5 of 11

Lab Studies:

• None indicated for uncomplicated cases

Imaging Studies:

• None indicated for uncomplicated cases

Procedures:

• Skin biopsy may be useful if the diagnosis is in doubt or to exclude other diseases in the differential.

TREATMENT

Section 6 of 11

Prehospital Care:

• In most cases, prehospital care involves providing simple first aid to treat patient symptoms.

• In severe cases, patients may develop second-degree burns, which could require aggressive fluid resuscitation and skin care.

Emergency Department Care:

• Most sunburns, while painful, are not life threatening, and treatment is primarily symptomatic.

• Aspirin and nonsteroidal anti-inflammatory drugs (NSAIDs) have antiprostaglandin effects and are useful to relieve pain and inflammation, especially when given early. Cool soaks with water or Burrow solution also provide temporary relief.

• Systemic steroids may shorten the course and reduce the pain of sunburn when given early and in relatively high doses (equivalent to 40-60 mg/d of prednisone).

• When used, prescribe them for only a few days, with no need for a taper.

• In the presence of severe second-degree burns, steroids are best avoided because they increase the risk of infection.

• Topical steroids show minimal, if any, benefit.

• Severe cases may require treatment of accompanying dehydration or secondary infection.

• Severe cases may be associated with other heat-related illnesses, including heat exhaustion and heat stroke.

• In rare cases, patients may require admission to a burn unit for aggressive skin care, intravenous fluids, and electrolyte management. Shock can occur.

• Prophylaxis against sunburn may be possible if a patient is treated with systemic steroids, equivalent to a daily dose of 60-80 mg of prednisone (1.0-1.5 mg/kg), prior to or shortly following sun exposure.

Consultations:

• Consult a dermatologist if the diagnosis of sunburn is in doubt or for children who appear to burn easily. In the latter case, a more serious underlying disorder may be present.

• Severe cases may require consultation with pediatricians or internists for hospital admission. Patients rarely require care in a dedicated burn unit.

MEDICATION

Section 7 of 11

The symptoms of minor sunburn can be relieved to some extent with cool compresses or a cool bath. Administration of nonprescription analgesics and NSAIDs for the treatment of pain and inflammation is recommended.

Drug Category: Analgesics -- Pain control is essential to quality patient care. It ensures patient comfort. Most analgesics have sedating properties, which are beneficial for patients who have sustained sunburns.

Drug Name	Aspirin (Bayer, Anacin, Bufferin) -- Used for the treatment of mild to moderate pain. Also acts on the hypothalamus heat-regulating center to reduce fever.
Adult Dose	650 mg PO bid/tid/qid; not to exceed 4 g/d in equally divided doses
Pediatric Dose	10-15 mg/kg/dose PO q4-6h; not to exceed 60-80 mg/kg/d
Contraindications	Documented hypersensitivity; liver damage; hypoprothrombinemia; vitamin K deficiency; bleeding disorders; asthma; children ( <16 y) with flu (because of association with Reye syndrome)
Interactions	Effects may decrease with antacids and urinary alkalinizers; corticosteroids decrease salicylate serum levels; additive hypoprothrombinemic effects and increased bleeding time may occur with coadministration of anticoagulants; may antagonize uricosuric effects of probenecid and increase toxicity of phenytoin and valproic acid; doses > 2 g/d may potentiate glucose-lowering effect of sulfonylurea drugs
Pregnancy	D - Unsafe in pregnancy
Precautions	May cause transient decrease in renal function and aggravate chronic kidney disease; avoid use in patients with severe anemia, with history of blood coagulation defects, or taking anticoagulants

Drug Name	Ibuprofen (Advil, Motrin, Nuprin) -- Usually the DOC for the treatment of mild to moderate pain, if no contraindications are present.
Adult Dose	200-400 mg PO q4-6h while symptoms persist; not to exceed 3.2 g/d
Pediatric Dose	30-70 mg/kg/d PO tid/qid
Contraindications	Documented hypersensitivity; peptic ulcer disease; recent GI bleeding or perforation; renal insufficiency; high risk of bleeding
Interactions	Coadministration with aspirin increases risk of inducing serious NSAID-related adverse effects; probenecid may increase concentrations and, possibly, toxicity of NSAIDs; may decrease effect of hydralazine, captopril, and beta-blockers; may decrease diuretic effects of furosemide and thiazides; monitor PT closely (instruct patients to watch for signs of bleeding); may increase risk of methotrexate toxicity; phenytoin levels may be increased when administered concurrently
Pregnancy	B - Usually safe but benefits must outweigh the risks.
Precautions	Category D in third trimester of pregnancy; caution in congestive heart failure, hypertension, and decreased renal and hepatic function; caution in anticoagulation abnormalities or during anticoagulant therapy

Drug Name	Acetaminophen (Tylenol, Aspirin Free Anacin, Feverall) -- DOC for treatment of pain in patients with documented hypersensitivity to aspirin, upper GI disease, or oral anticoagulants.
Adult Dose	325-650 mg PO q4-6h or 1000 mg tid/qid; not to exceed 4 g/d
Pediatric Dose	<12 years: 10-15 mg/kg/dose PO q4-6h prn; not to exceed 2.6 g/d >12 years: 325-650 mg PO q4h; not to exceed 5 doses in 24 h
Contraindications	Documented hypersensitivity; G-6-PD deficiency
Interactions	Rifampin can reduce analgesic effects of acetaminophen; coadministration with barbiturates, carbamazepine, hydantoins, and isoniazid may increase hepatotoxicity
Pregnancy	B - Usually safe but benefits must outweigh the risks.
Precautions	Hepatotoxicity possible in chronic alcoholics following various dose levels; severe or recurrent pain or high or continued fever may indicate serious illness; acetaminophen is contained in many OTC products and combined use with these products may result in cumulative acetaminophen doses exceeding recommended maximum dose

Drug Category: Corticosteroids -- Have anti-inflammatory properties and cause profound and varied metabolic effects. Corticosteroids modify the body's immune response to diverse stimuli. May shorten the course and reduce the pain of sunburn.

Drug Name	Prednisone (Deltasone, Orasone, Meticorten) -- May decrease inflammation by reversing increased capillary permeability and suppressing PMN activity.
Adult Dose	40-60 mg PO qd
Pediatric Dose	1 mg/kg PO qd
Contraindications	Documented hypersensitivity; viral infection, peptic ulcer disease, hepatic dysfunction, connective tissue infections, and fungal or tubercular skin infections; GI disease
Interactions	Coadministration with estrogens may decrease prednisone clearance; concurrent use with digoxin may cause digitalis toxicity secondary to hypokalemia; phenobarbital, phenytoin, and rifampin may increase metabolism of glucocorticoids (consider increasing maintenance dose); monitor for hypokalemia with coadministration of diuretics
Pregnancy	B - Usually safe but benefits must outweigh the risks.
Precautions	Abrupt discontinuation of glucocorticoids may cause adrenal crisis; hyperglycemia, edema, osteonecrosis, myopathy, peptic ulcer disease, hypokalemia, osteoporosis, euphoria, psychosis, myasthenia gravis, growth suppression, and infections may occur with glucocorticoid use

FOLLOW-UP

Section 8 of 11

Further Inpatient Care:

• Inpatient care is indicated for severe burns, secondary infection, or control of severe pain.

• Indications for admission to a dedicated burn unit are the same as those for thermal burns.

Further Outpatient Care:

• Outpatient care is indicated for most cases of sunburn.

• Cool baths or showers

• Anti-inflammatory/analgesic medications

• Avoidance of further sun exposure

In/Out Patient Meds:

• Topical anesthetic sprays or creams may cause sensitization and consequent dermatitis and, therefore, should be avoided.

Transfer:

• Only the most severe cases of sunburn, with marked involvement of a large percentage of the body surface area, require transfer to a burn unit for treatment.

Deterrence/Prevention:

• Prevention is the most effective therapy for sunburn. Individual and community educational programs can be effective in decreasing overall sun exposure or increasing use of sunscreen or protective clothing.

• Avoid sun exposure, especially during the period of peak solar radiation flux (from 10 am to 2 pm).

• Wear protective clothing, including hats or sun visors.

• Regularly use sunscreens with an adequate sun protection factor (SPF) for a given skin type (see Race).

• SPF refers to the time needed to produce erythema on protected skin as a factor of the time to produce erythema on unprotected skin.

• In general, use of a sunscreen with an SPF of 30 is sufficient.

• Apply at least 30 minutes prior to sun exposure and reapply often.

• Use waterproof sunscreens when swimming or perspiring heavily.

• Physical barriers (eg, zinc oxide, talc, titanium dioxide) provide excellent protection but are less appealing cosmetically.

• Chemical barriers are used in most sunscreens. Para-aminobenzoic acid (PABA) and PABA esters, which diffuse into stratum corneum and bind, are used most commonly, but they may stain clothing or produce contact dermatitis. Other chemical blocking agents include cinnamates, salicylates, anthranilates, and benzophenones. Many sunscreens employ a combination of agents.

Complications:

• Sunburns can exacerbate other skin diseases.

• Sunburns may trigger recurrence of herpes simplex, lupus, porphyria, or other cutaneous disorders.

• Sunburns may be associated with other heat-related illnesses, including dehydration, heat exhaustion, and heatstroke.

• Long-term exposure of the skin can lead to multiple deleterious effects, including premature aging and wrinkling of the skin (dermatoheliosis), development of premalignant lesions (solar keratoses), and development of malignant tumors (eg, basal cell carcinoma, squamous cell carcinoma, melanoma).

• Excessive exposure of the eyes to UVR can lead to discoloration of the lens and nuclear cataract formation.

• Photokeratoconjunctivitis, or snow blindness, may exist concurrently with sunburn.

Prognosis:

• Uncomplicated cases of sunburn resolve spontaneously over 4-7 days with scaling and desquamation but without acute sequelae.

• Long-term exposure to UVR is associated with several deleterious effects on the skin, as delineated above.

Patient Education:

• Short- and long-term complications (see Complications)

• Prevention (see Deterrence/Prevention)

• For excellent patient education resources, visit eMedicine’s Burns Center. Also, see eMedicine’s patient education article Sunburn.

MISCELLANEOUS

Section 9 of 11

Medical/Legal Pitfalls:

• Since window glass blocks UV-B, patients presenting with solar reactions occurring from exposure through window glass should be evaluated for phototoxic reactions and porphyria.

• Easy sunburning during infancy may indicate a serious underlying disease, such as porphyria or xeroderma pigmentosum. Referral for further evaluation is prudent.

• Obtain a complete drug exposure history in any patient with a rash.

Special Concerns:

• Avoid use of PABA and PABA esters on children younger than 6 months.

TEST QUESTIONS

Section 10 of 11

CME Question 1: A 21-year-old woman presents to the ED with a painful sunburn. She states that she seldom tans but nearly always burns. After providing her with appropriate treatment, she is advised to use sunscreen on a regular basis. What is the minimum recommended sun protection factor (SPF) for this woman?

A: No sunscreen necessary
B: 4
C: 10
D: 15
E: 30

The correct answer is E: She is skin phototype II and should always use a sunscreen with an SPF of 30 or higher.

CME Question 2: A 5-month-old boy is brought to the ED with significant cutaneous erythema that occurred while playing inside, next to a large glass window. The parents mention that he has had similar problems in the past. In addition to providing appropriate care, what other step should be taken?

A: Contact child protective services to report a case of child neglect.
B: Advise the parents to use para-aminobenzoic acid (PABA)-containing sunscreens.
C: Refer the infant for further evaluation to rule out a potentially serious underlying condition.
D: Prescribe aspirin to control the pain and inflammation.
E: None of the above.

The correct answer is C: Easy sunburning during infancy, especially through a glass window, may herald a more serious underlying disease, such as porphyria or xeroderma pigmentosum.

Pearl Question 1 (T/F): The maximal flux of solar radiation occurs at 4 pm.

The correct answer is False: The period of maximum solar radiation flux occurs between 10 am and 2 pm.

Pearl Question 2 (T/F): Sunburn can occur on areas of the body that are covered by clothing.

The correct answer is True: Some clothing allows the penetration of a significant amount of ultraviolet radiation.

Pearl Question 3 (T/F): A typical case of sunburn resolves in 2 weeks.

The correct answer is False: A typical case of sunburn resolves within 4-7 days.

Pearl Question 4 (T/F): Dermatoheliosis is the wrinkling and aging of the skin.

The correct answer is True: Dermatoheliosis is premature aging and wrinkling of the skin caused by long-term sun exposure.

BIBLIOGRAPHY

Section 11 of 11

• Balk SJ, O'Connor KG, Saraiya M: Counseling parents and children on sun protection: a national survey of pediatricians. Pediatrics 2004 Oct; 114(4): 1056-64[Medline].
• Bickers DR: Sun-induced disorders. Emerg Med Clin North Am 1985 Nov; 3(4): 659-76[Medline].
• Cavallo J, DeLeo VA: Sunburn. Dermatol Clin 1986 Apr; 4(2): 181-7[Medline].
• Dietrich AJ, Olson AL, Sox CH, et al: A community-based randomized trial encouraging sun protection for children. Pediatrics 1998 Dec; 102(6): E64[Medline].
• Godar D: UV Doses Worldwide. Photochem Photobiol 2005 Aug 1;[Medline].
• Green A, Williams G, Neale R, et al: Daily sunscreen application and betacarotene supplementation in prevention of basal-cell and squamous-cell carcinomas of the skin: a randomised controlled trial. Lancet 1999 Aug 28; 354(9180): 723-9[Medline].
• Hall HI, McDavid K, Jorgensen CM, Kraft JM: Factors associated with sunburn in white children aged 6 months to 11 years. Am J Prev Med 2001 Jan; 20(1): 9-14[Medline].
• Kramer DA, Steinmark R: Sun-induced disorders. In: Schwartz GR, et al, eds. Principles and Practice of Emergency Medicine. 3rd ed. Philadelphia: Lippincott Williams & Wilkins; 1992:2897-2904.
• Moehrle M, Koehle W, Dietz K, Lishka G: Reduction of minimal erythema dose by sweating. Photodermatol Photoimmunol Photomed 2000 Dec; 16(6): 260-2[Medline].
• Norris PG, Gange RW, Hawk JL: Acute effects of ultraviolet radiation on the skin. In: Fitzpatrick TB, et al, eds. Dermatology in General Medicine. 4th ed. NY: McGraw-Hill; 1993:1651-8.
• Pathak MA, Fitzpatrick TB: Preventive treatment of sunburn, dermatoheliosis, and skin cancer with sun-protective agents. In: Fitzpatrick TB, et al, eds. Dermatology in General Medicine. 4th ed. NY: McGraw-Hill; 1993:1689-98.
• Perpall A: Selected environmental skin disorders. Emerg Med Clin North Am 1992 May; 10(2): 437-48[Medline].
• Potts JF: Sunlight, sunburn, and sunscreens. Preventing and remedying problems from 'too much fun in the sun'. Postgrad Med 1990 Jun; 87(8): 52-5, 59-60, 63[Medline].
• Van Laethem A, Claerhout S, Garmyn M: The sunburn cell: regulation of death and survival of the keratinocyte. Int J Biochem Cell Biol 2005 Aug; 37(8): 1547-53[Medline].

eMedicine Journals > Emergency Medicine > Environmental > Sunburn

Please email us with any comments you have on our new chapter format.

Author Information | Introduction | Clinical | Differentials | Workup | Treatment | Medication | Follow-up | Miscellaneous | Test Questions | Bibliography