Sunburn and Sun Poisoning Facts
- Sunburn is an inflammation of the skin caused by overexposure to UV radiation from the sun.
- UV radiation damages the skin and also can damage the eyes.
- UV rays are most intense at noon and the hours immediately before and after (between 10AM and 3PM).
- Immediate symptoms of sunburn are hot, red, tender skin; pain when the skin is touched or rubbed; and dehydration; several days after exposure the skin may swell, blister, and peel.
- Most sunburns are mild and can be treated with home remedies such as applying damp cloths or compresses to reduce the pain, soaking in a tepid bath (with no soap), gently patting the skin dry, applying soothing creams or lotions, OTC pain relievers such as Tylenol or others, and moisturizing the skin.
- Sunburn may cause permanent skin damage and skin cancer (malignant melanoma, basal cell carcinoma, squamous cell carcinoma).
- UVB as well as UVA rays may cause damage to skin.
- UV rays may bounce off water, sand, snow, and other surfaces.
- Some types of skin tan after exposure to UV rays because after repeated or prolonged exposure to UV rays the skin produces more melanin.
- Persons with certain pigment disorders and individuals with fair skin are at most risk of sunburn.
- Certain diseases and conditions pose a higher risk of sunburn (for example, albinism, lupus, porphyrias, vitiligo, and xeroderma pigmentosum).
- Some medications may increase sensitivity to sunburn (photosensitivity).
- The best way to prevent sunburn is to avoid long exposure to sunlight.
- Sunscreen and sun-protective clothing are important measures to limit sun damage.
- Apply sunscreen before going outdoors, apply it liberally, and re-apply frequently.
- Sun poisoning is caused by severe sunburn; its symptoms include fever, nausea, chills, dizziness, rapid pulse, rapid breathing, dehydration, and shock.
- Heat stroke is a severe form of hyperthermia that is life-threatening.
What is sunburn?
Sunburn is an inflammation of the skin that is caused by overexposure to ultraviolet (UV) radiation from the sun. A similar burn can follow overexposure to a “sun” (UV or tanning) lamp. UV radiation can also damage the eyes, although no surface burn is apparent.
Sunburn is a very common condition. In the United States, approximately 30% to 40% of adults and close to 80% of children and adolescents report having at least one sunburn in the preceding year.
Can sunburn cause permanent damage?
Yes. Sunburn early in life increases the risk of developing skin cancer later on. Repeated overexposure to ultraviolet rays can also scar, freckle, dry out, and wrinkle the skin prematurely. In addition, frequent overexposure to ultraviolet rays can increase the risk of developing eye cataracts and macular, a leading cause of blindness.
What is UV light?
UV light is radiation energy in the form of invisible light waves. UV light is emitted by the sun and by tanning lamps.
The sun discharges three types of ultraviolet radiation:
- ultraviolet A (UV-A),
- ultraviolet B (UV-B), and
- Ultraviolet C (UV-C).
Only UV-A and UV-B rays reach earth. (UV-C does not penetrate the earth’s upper atmosphere.)
Although research has long implicated UV-B as the most likely form of UV radiation to damage the skin and cause skin cancer, it is now known that UV-A also can be dangerous. UVB is known to affect the outer layer of skin. UVA is much less intense than UVB, but it is about 50 times more likely than UVB to reach deeper layers of skin to cause sun damage.
Tanning lamps also produce UV-A and/or UV-B. These artificial rays affect the skin in the same way as do UV-A and UV-B from the sun.
When and where are UV rays most intense?
UV rays are most intense at noon and the hours immediately before and after (between 10 a.m. and 3 p.m.), particularly in the late spring, summer, and early autumn. Although they are less concentrated at other times of the day and year, UV rays can still damage the skin and eyes – even in the dead of winter and on cloudy or rainy days.
UV rays also increase in intensity in relation to altitude and latitude. The higher the altitude, the greater is the concentration of UV rays. Likewise, the rays are more powerful the nearer to the equator.
UV rays “bounce” off reflective surfaces – including water, sand, and snow. Thus, a skier, swimmer, fisherman, or beachcomber may be bombarded with UV rays from above and below.
What are the symptoms of sunburn?
- Some of the immediate symptoms of sunburn after exposure are the following:
- First, the skin becomes red, tender and hot.
- Touching or rubbing the skin causes pain.
- Because heat triggers fluid loss, a sunburn victim can also become dehydrated.
- For several days after exposure, the skin may swell, blister, and peel. Some sufferers develop welts or rashes.
- Skin peeling can occur several days later after a sun rash develops and is a sign of healing and rebuilding of skin.
- More subtle exposures to the sun may not have any obvious immediate symptoms such as the ones listed above. Most sunburns are mild causing only skin redness, pain, and irritation due to involvement of the outer layer of skin (first degree burn). This type of burn may be painful to touch.
- The skin is swollen, very red, and painful blisters may occur. This may indicate a more moderate sunburn (second degree burn). This type of sun rash may take longer to heal.
- People who have chronic (long standing) exposure to sun can increase their changes of developing chronic skin damage from sun exposure (wrinkles, aging, age spots, freckles, skin cancer, scarring, etc.).
The symptoms of sunburn can be mild, moderate, or severe, depending mainly on the following:
- The skin type of the person affected. (more detail to follow later in this article)
- The time, duration, location, and altitude of exposure.
- Medications the person has been taking (sun-sensitizing drugs that may increase a person’s susceptibility to sunburn).
- Skin preparations (sunscreen) the person has been using.
What are the symptoms of severe sunburn (sun poisoning)?
In severe cases of sunburn, the individual may experience:
- rapid pulse
- rapid breathing
- heat stroke (a severe form of hyperthermia that constitutes a medical emergency)
- shock with loss of consciousness, and/or
- Severe blisters or soreness
- Severe cases of sunburn require emergency medical treatment
What first-aid measures should be taken with sunburn?
If symptoms of severe sunburn are present, the individual should contact their primary health care practitioner, urgent care facility, or Emergency Department. While awaiting treatment, the affected person should not drink cold water, which can trigger chills. If compresses are applied, they should be dipped in cool or tepid water, not cold water.
If the symptoms of sunburn are mild or moderate, the patient may drink plenty of water to replenish the fluid lost from the sunburn and to avoid dehydration. Other simple home remedies for sunburn are listed in the following sections.
What is the treatment for sunburn?
- Certain medical treatments have been tried and studied to treat sunburn. However, in general, most remedies have not shown any clinically proven benefit as far as speeding the recovery or reversing the damage. Therefore most of the treatments available are only used to treat symptoms.
- Nonsteroidal anti-inflammatory drugs(NSAIDs) in oral (ibuprofen, Motrin, Naprosyn, Advil etc.) or topical diclofenac 0.1% gel (Solaraze) forms have shown to reduce redness if applied before or immediately after UVB exposure. This benefit may be diminished after 24 hours. It should be noted that these medications may also help relieve the symptoms of sunburn such as pain and discomfort.
- Topical steroid creams were also studied, but these did not show any significant improvement. Oral steroids such asprednisone did not prove beneficial and have been associated with some significant side effects.
- Applying Aloe Vera gel to the skin has also not been beneficial in treating the actual sunburn. However, this may be beneficial in treating the symptoms.
- Other advertised remedies such as topical anaesthetics (benzocaine) may help with symptoms of sunburn, however, very little clinical data is available to substantiate their effectiveness.
Are there any home remedies to treat sunburn?
There are some simple measures that can be applied at home to help with sunburns. The easiest and most important remedy to sunburn is using effective preventative measures to avoid sunburn. These steps include:
- Do not spend too much time in the sun, especially in direct sunlight midday.
- Wear protective clothing – long-sleeved shirts, hats with a large brim, and use sunscreen.
- Drink water to keep hydrated while spending time in the sun.
- Once sunburn occurs, there are sunburn remedies that can help with treating sunburn symptoms.
- Apply dampened cloths or compresses to reduce the heat and lessen the pain.
- Soak in a bathtub of plain, soap-free water (soap can irritate the burn).
- Gently pat the skin dry afterward – do not rub it.
- Apply a soothing cream, lotion, or another preparation approved by a physician or pharmacist
- Note that some preparations, in particular those containing benzocaine (Endocaine, Hurricaine), can trigger an allergic reaction in some individuals, and certain ointments can retard healing by sealing off the skin from the air.
- If the discomfort is significant, take an OTC painkiller such asacetaminophen (Tylenol and others) or ibuprofen (Advil, Children’s Advil/Motrin, Medipren, Motrin, Nuprin, PediaCare Fever, and others)
- These medications also can be used to treat headache associated with sunburn. Additionally, headache may be caused by dehydration. Drinking plenty of fluids (no caffeine or alcohol) is one way to prevent dehydration while out in the sun for prolonged periods of time.
- Moisturizing measures with creams or Aloe Vera gel may also help with symptoms of sunburn.
- If blisters form after sunburn, do not attempt to burst or “pop” them unless they are located in a very painful area, or are otherwise causing a lot of discomfort due to size. Most blisters will break by themselves if they are left alone. Blisters are better left uncovered as rubbing or placing a tight cover over them may cause infections and more discomfort. If blisters need to be covered, for example, because they cause discomfort by rubbing on clothes, they should be covered by a loosely applied dressing.
- Once a sunburn blister breaks, home remedies to treat them are simple and practical. The area of the broken blister should be kept clean by washing it frequently with soap and water. The left over skin should be left alone, but cleaned, until it falls off. Broken blisters generally heal on their own, but they are susceptible to infections. Topical antibiotic ointments can be applied to the area of broken blisters to prevent infections.
- If a sun blister is uncomfortable or too large or located in a cosmetically unappealing area, consider breaking it carefully. This could be done by gently cleaning the area well with soap and water or rubbing alcohol and using a clean needle to punch a hole at the edge of the blister gently. The fluid inside can be pushed towards the hole and drained. The area should be cleaned again and covered with a loose dressing afterwards. Topical antibiotics can be applied to the broken blister also in order to reduce the risk of infection.
Is a follow-up visit with a physician necessary?
A follow-up visit with a physician is not necessary unless the sunburn was severe (sun poisoning). However, every patient who has suffered significant sunburn should report the incident to his or her doctor so that the burn can become part of the patient’s medical history. Doing so will alert the physician, during future check-ups, to look closely for symptoms of skin cancer and other problems that sunburn can cause.
Why does the skin tan after exposure to UV rays?
The skin contains a pigment called melanin. It colours the skin, imparting the variety of skin tones we all recognize.
Melanin blocks at least some of the UV rays from penetrating the skin. After repeated or prolonged exposure to UV rays, the skin produces more melanin. Consequently, the skin darkens, or tans, which in turn protects the skin to a certain degree.
Who is most susceptible to sunburn?
Persons with certain pigment disorders (such as albinism) and persons with fair skin are at highest risk of suffering a burn. The American Academy of Dermatology classifies skin types into six categories (in terms of susceptibility to sunburn) for skin colours ranging from fair to black. This is called the Fitzpatrick classification. These skin types are as follows:
Types 1 and 2: High Susceptibility to Sunburn
- Individuals with Skin Type 1 have very fair skin (pale or milky white), blond or red hair, and possibly freckles. Such persons can suffer a burn in less than one-half hour when exposed to summer sunlight at midday. People with Skin Type 1 never tan.
- Individuals with Skin Type 2 have very light brown skin and possibly freckles. They burn in a short time in the sun, although they can achieve a very light tan.
Types 3 and 4: Moderate Susceptibility to Sunburn
- Individuals with Skin Type 3 (called “average Caucasians” by The American Academy of Dermatology) have skin that is slightly more brown than the skin of a Type 2. They can develop a moderate sunburn and a light brown tan.
- Individuals with Skin Type 4 have olive-coloured skin. Ordinarily, they develop only minor sunburn while acquiring a moderate tan.
Types 5 and 6: Minimal or No Susceptibility to Sunburn
- Individuals with Skin Type 5 have brown skin and can develop a dark tan while rarely burning.
- Individuals with Skin Type 6 have black skin and never burn.
It is often difficult to accurately determine an individual’s skin type simply by looking at the colour of the skin. It is best to ask the person how quickly they may burn and how easily they tan. Based on the response to these simple questions, the skin type can be determined.
Can diseases cause a heightened sensitivity to UV rays?
Yes. Certain disorders place their sufferers at very high risk of skin damage — including severe sunburn, blisters, and sores — from exposure to UV radiation. The following is a small sample of afflictions that increase the skin’s sensitivity to UV radiation:
- Albinism: Individuals with classic oculocutaneous lack melanin in their skin and eyes — hence, the term “oculocutaneous” (“oculo” for eyes, and “cutaneous” for skin). Without the protection of this pigment, their white skin and pink eyes are both highly sensitive to UV and susceptible to the rays’ damage.
- Systemic lupus erythematosus: Individuals with lupus can have inflamed tissues, including the skin on the face. The “butterfly” rash (or malar rash) of lupus over the cheeks and nose is extremely sensitive to UV rays. In fact, UV-B and UV-A rays can cause lupus to flare. This butterfly rash and its sensitivity to sun is one of common characteristics of lupus.
- Porphyrias: The porphyrias are disorders of specific enzymes that are needed for the metabolism of heme (part of the pigment hemoglobin that permits red blood cells to transport oxygen and carbon dioxide). Patients with these disorders manufacture abnormally large amounts of substances called porphyrins. Stimulation of the excess porphyrins in the skin by the UV rays causes damage and scarring of the skin. This skin damage is a prominent feature of several forms of porphyria including porphyria, hereditary coproporphyria, variegate porphyria, and, particularly, congenital erythropoietic porphyria.
- Vitiligo: Vitiligo is a relatively common disorder that causes patches of white de-pigmented skin. These patches lack melanin and are extremely sensitive to UV rays.
- Xeroderma pigmentosum: This disorder appears to result from an inherited hypersensitivity to the cancer-causing (carcinogenic) effects of ultraviolet light. Sunlight causes DNA damage that is normally repaired. Individuals with xeroderma pigmentosum have defective inability to repair the DNA after UV damage. Affected individuals are hundreds of times more vulnerable to developing skin cancer than other people. Their extreme skin photosensitivity predisposes them to pronounced skin damage and scarring but also to the early onset of skin cancer (basal cell and squamous cell carcinomas and malignant melanoma).
Can medications increase sensitivity to sunburn?
A large number of medications are known to increase skin sensitivity to sunlight and are called photosensitive drugs or medications. Some of the common ones include:
- NSAIDs (nonsteroidal anti-inflammatory drugs)
- Antibiotics: Tetracyclines (tetracycline, doxycycline [Vibramycin]), Quinolone (ciprofloxacin [Cipro], levofloxacin[Levaquin]), Sulfonamides (sulfamethoxazole and trimethoprim; cotrimoxazole [Bactrim, Septra], sulfamethoxazole [Gantanol]).
- Diuretics (water pills): thiazides (hydrochlorothiazide [Hydrodiuril],furosemide [Lasix])
- Cardiac medications: amiodarone(Cordarone), quinidine
- Diabetes drugs: sulfonylureas such as chlorpropamide (Diabinese),glyburide (Micronase, DiaBeta, Glynase)
- Psychiatric drugs: chlorpromazine (Thorazine), antidepressants like desipramine (Norpramin) and imipramine (Tofranil)
- Acne medications: isotretinoin(Accutane)
What kinds of skin cancer can UV rays cause?
- Overexposure to UV rays can cause three varieties of skin cancer; malignant melanoma, basal cell carcinoma, and squamous cell carcinoma.
- Malignant melanoma
- Malignant melanoma is by far the most dangerous form of skin cancer.
- The current lifetime risk of developing a melanoma is approximately 1/60.
- Melanomas may begin from changes in a pre-existing mole or birthmark, or arise as a brand new mole from otherwise clear skin (de novo).
- Multiple features are more common in melanomas versus regular moles including asymmetry, irregular borders, multiple colours, and size larger than a pencil eraser.
- Melanomas may be black or brown – and sometimes red, white or blue, or a mixture of those Melanoma can spread (metastasize) rapidly. If diagnosed early, melanoma is often curable.
- However, if the diagnosis is delayed, melanoma can spread and may be potentially fatal.
Basal and squamous cell carcinomas
Basal and squamous cell cancers are slow-growing and are far less likely to metastasize (spread to other parts of the body) than melanoma. Both basal and squamous cell cancers can be cured in at least 90 percent of the cases if diagnosed early.
Basal cell carcinoma
Basal cell carcinomas are flattened, pearly, small bumps with translucent edges and slightly depressed centres. They may bleed. Usually, they appear on the head, neck, upper trunk, and hands. If ignored, these cancers can cause considerable localized damage.
Squamous cell carcinoma
Squamous cell carcinomas are rough patches or crusty scaly areas on the skin that do not clear up and do not respond to the usual skin creams. They may bleed a little. They tend to appear particularly on the ear rims, face, lower lip, and hands. If ignored, they can spread to other parts of the body.
These conditions are very common and if diagnosed properly and promptly, they are highly curable. Therefore it is very important to have routine skin checks by a trained skin doctor (dermatologist) annually. Annual screening can help in early diagnosis of skin cancer or pre-cancerous conditions that may lead to skin cancer.
How can sunburn and skin cancer be prevented?
The ideal methods of preventing sunburn, and hopefully skin cancer, involve:
- Limit the amount of time of sun exposure and avoiding the peak sunshine hours of late morning to early mid-day, generally 10 a.m. to 4 p.m.;
- Wear protective clothing such as a broad-brimmed hat (at least 6 inches), UV protected sunglasses and clothing, long- legged pants, and shirts with sleeves that cover the arms (thicker fabrics and dark clothing in general protect better compared with light clothing – there are clothing products available that offer “UV” protection);
- Be aware that sunburn can occur even on a cloudy day (clouds don’t stop the ultraviolet rays), and even when you are in the water;
- Remember that sand, water, and snow reflect the sun’s rays and increase the chance of burning during beach activities or skiing; and
- Use a protective sunscreen to minimize the penetration of UV rays. Sunscreens with a skin protection factor (SPF) of at least 15 are recommended for everyone, even dark-skinned individuals, exposed to the sun. It is recommended that light skinned people use a higher SPF when in direct sun. This should be applied several minutes before going into the sun and reapplied often.
- Avoid tanning beds and sun lamps.
How do sunscreens work?
Sunscreens protect the skin by absorbing or reflecting the UV radiation. It is important to realize that many available sunscreens protect mainly against UVB and may not adequately protect against long standing UVA exposure.
Sunscreens may be classified into two groups, physical sunscreens and chemical sunscreens.
- Physical sunscreens Physical sunscreens act by reflecting and scattering the UV rays (A and B) and thus, limiting their exposure to the skin. They include chemicals such as zinc oxide, titanium dioxide, ferric chloride, ichthamnol, and talc. Their use has been somewhat limited by their opaque appearance and tendency to stain clothing. Current preparations of zinc oxide are more cosmetically acceptable and easier to use.
- Chemical sunscreens Chemical sunscreens work by absorbing the light prior to reaching the skin.
Traditionally, these sunscreens have protected mainly against UVB rays.
Some examples of this group include para-aminobenzoic acid (PABA), PABA esters, salicylates, and camphor derivatives.
More recently, newer sunscreens have been developed to also absorb UVA rays such as avobenzone, Mexoryl, dibenzoylmethanes, anthranilates, benzophenones, triazoles, and some camphor derivatives.
PABA has been essentially phased out of sunscreen preparations because of the high rate of allergic reactions to this chemical.
The most recommended practice is to use a combination of physical and chemical sunscreens for the most adequate protection.
What is SPF?
SPF, or Sun Protection Factor, is the measurement of how well an agent may protect against sunburn. SPF can be calculated from the amount of time that it takes to develop mild redness or burning in an unprotected person. For example, if someone develops mild sunburn-related redness in 20 minutes, he or she may develop the same degree of redness in 300 minutes (5 hours) with an SPF 15 sunscreen (15 times 20 minutes) when properly applied.
Traditionally, the SPF is rated for sun damage by UVB rays only. A new regulation by the Food and Drug Administration (FDA) in June 2011, requires the industry to change their labels to also include protective potential against UVA radiation. This change is very important because UVA is responsible for a significant portion of sun damage to people. This new “broad spectrum” label information requirement will take effect in 2012. The final regulations for sunscreen labelling provisions include:
Sunscreen products that are not “broad spectrum” with SPF values from 2 to 14 will be labelled with a warning that reads: “Skin Cancer/Skin Aging Alert.”
Water resistant sunscreen claims must have information in regard to how much time a person can expect to have the declared SPF level of protection while sweating or swimming.
Two times will be permitted on the labels: 40 or 80 minutes.
Manufactures can no longer make claims that sunscreens are “waterproof” or “sweat proof” or identify their products as “sun blocks.”
What is the best way to apply sunscreen?
It advised to apply sunscreen 15 to 30 minutes before expected sun exposure. Reapplication of sunscreen every 1-2 hours is also generally advised. Some experts, however, encourage more frequent reapplication, especially shortly after initial exposure. It is also important to apply sunscreen very liberally; spreading the product too thin may not achieve the desired degree of protection. A general recommendation is to apply an amount similar to the size of a golf ball for a person of average build.
Sunscreen sprays also are becoming more available and popular. They are generally effective; however, some questions have been raised in regard to the amount of spray that actually adheres to the body once applied. The spray can be dispersed by wind, insufficient amount may be sprayed, or the sunscreen is sprayed too far from the body. It is recommended that sunscreen sprays be used in conjunction with other more traditional topical sunscreens for the best sun protection.
SPF 15 sunscreen is the minimum requirement for most individuals. Stronger sunscreens are recommended for people who easily burn in the sun and have longer exposure time in the sun. Water exposure may wash off the sunscreen so it should be reapplied after the body dries up.
Do sunscreens expire?
Sunscreens may degrade over time or after long exposure to sun and heat. Therefore, the bottle should not be kept in the car or under direct sun exposure for a long period of time. If the expiration date has passed, the product needs to be discarded and replaced with a new one. Sunscreens generally expire or lose their effectiveness after about three years.
Can antioxidants protect against sunburn?
Antioxidants are agents that can prevent certain harmful reactions in the body. The formation of some potentially harmful molecules, called free radicals, is one of these reactions. Antioxidants are natural agents that may prevent or reduce this formation.
Some of sun damage is a result of this reaction. Oral or topical antioxidants (vitamins A, C, and E, and green tea) may theoretically protect the skin against sunburn. Clinical data is not sufficient to support their use instead of or in addition to, traditional sunscreen.