Sun allergy rash also called photosensitivity is occurs when your body reacts to overexposure to the sun. The sun emits harmful rays known as Ultraviolet rays that can damage the skin. When allergic to the sun, you are likely to develop a red itchy rash on the areas of skin that were exposed to the sun.
Like with other autoimmune condition, the body will activate the immune system activity against sun-altered skin. This is what produces the allergic reaction that takes the form of a skin rash marked with tiny blisters.
Here are the causes, symptoms, natural remedies and what you need to do to prevent the allergy.
What cause sun allergy?
Sun allergy is attributed to excess exposure to harmful UV rays from the sun that triggers the immune system to cause a skin rash. The exact cause for this is however unknown.
Sunlight is made up of ultraviolet A (UVA) and ultraviolet B (UVB) rays. You can either be allergic to either one or both of the rays.
Studies show that these rays may cause change to the part of the body (skin) exposure directly to the sun. When this happens, the immune system is activated, it then mistakes the altered skin to foreign substance such as bacteria or a virus.
It then launches an attack that produces symptoms of an allergic reaction. These include swelling, redness and severe itching.
The same reaction can also result from chemical products applied on the skin or oral medication after exposure to the sun.
The sunlight may interact with these chemicals in your body which is then detected as foreign invaders. Your immune system becomes reactive producing allergy symptoms.
Types of sun allergy
Sun allergies are common in people with sensitive skin. In most cases, the reaction can be triggered by only a brief moment of exposure to the sun. Currently, it is not known why some people develop the allergy while others do not.
There different types of sun allergy. According to Harvard health publishing, there is evidence that some form of allergy is inherited. Common types include the following:
a) Polymorphous light eruption
PMLE often appear as an itchy rash after sun exposure. After a sunburn, it is the second most common sun-related skin problem seen by doctors. Statistics show it occurs in around 15% of US population, affecting people of all races, and ethnic backgrounds.
Women are more affected by this type, with symptoms typically starting during young adult life. It is rare in winters but common during spring and summer months.
As spring turns into summer, continued exposure causes the skin to become less sensitive, this is known as hardening, and usually, last through the summer. The rash may disappear or become less severe. It, however, return at full intensity the following spring.
This type can be shown by:
- Itching or burning rash on neck, arms, and lower legs
- Mild to a severe headache
- Red plaques on exposed parts of the body
- Small fluid-filled blisters
- Tiny areas of bleeding under skin
b) Actinic prurigo
Also known as hereditary PMLE. This type is common in people of American Indian background. Its symptoms are more intense than those of classic PMLE, and will often begin earlier during childhood or adolescence.
It is hereditary meaning several generations of the same family may have a history of the problem. Unlike classic PMLE, the symptoms of these conditions are concentrated on the face, especially around the lips.
c) Photoallergic eruption
In this form, the allergic reaction is triggered by the effects of sunlight on a chemical applied on the skin. These chemicals can be ingredients in sunscreen, cosmetic products, fragrances or topical antibiotics and other ointments.
The same reaction can occur result from ingested drugs. Antibiotics are common prescription drugs known to cause photoallergic eruptions. Other according to Harvard health publication includes:
- phenothiazine’s for psychiatric illness
- diuretics for high blood pressure
- certain oral contraceptives
- nonprescription pain relievers such as ibuprofen and naproxen sodium have also been linked to such reactions
This form can be shown by an itchy red rash or tiny blisters, in rare cases, the reaction may spread to other parts of the body covered with clothes. This is because the reaction is said to be a form of delayed hypersensitivity reaction.
Symptoms occur a few days after exposure to the sunlight.
d) Solar urticaria
This can be said to be the most severe form of sun allergy. It occurs within a few minutes of exposure to sunlight. It produces hives which can be described as large, itchy, red bumps. It is a rare condition that mostly affects young women.
Sun allergy rash
Sun rash or sunburn can be described as an intense inflammatory response of the skin to excessive sun exposure. A sun allergy is the body’s reaction to damaged tissue. It is also known as photodermatitis, sun poisoning or photoallergy.
Are there any differences between a sun allergy and sun poisoning? An allergy occurs when your immune system overreacts to sunlight exposure.
When allergy to the sun, you are likely to develop an itchy red rash on areas of the skin exposed to the sun. Rarely, patients may develop hives and blisters. Patient of all skin tones can develop skin allergies to the sun.
Sun allergy rash is often time characterized by swelling, a burning sensation, and a red itchy rash that resembles small blisters and peeling of the skin.
It may also cause blotches where the itching persist for long periods, in such cases, an unsightly orange to brown tint may form on the affected area.
A sun allergy is not a sunburn, it might, however, feel like it. Sun allergies are believed to be induced by changes that occur in sun-exposed skin, the real cause is however unknown.
Like most autoimmune conditions, the body will activate its defense against sun alerted skin.
As mentioned, sun allergy is the reaction of the body to sun damage caused by long exposure to the sun. Symptoms are common on the neck, back, hands and on outside surface of the arms and the lower leg.
In most of the cases, the symptoms will vary depending on the specific types of the allergy.
Common signs of the allergy will, however, include the following:
- Severe itching and a burning rash
- Chills and headaches
- Red raised plaques on the affected part of the skin
- Red blotches
- Painful fluid-filled blisters
- Bleeding under the skin
- Swelling and redness on the affected skin
Sun allergy treatment
Once you develop a sun allergy, we recommend you reduce exposure to the sun to prevent the symptoms from worsening. In most cases, treatment will often depend on the specific type of allergy one is suffering from.
To get rid of the rash, itching, redness and skin inflammation caused by a sunburn, your dermatologist might prescribe any of the following options:
- Oral antihistamine to get rid of the hives, redness and mild to severe itch. Healthcare providers will often prescribe antihistamines for patients with PMLE.
- For mild itching, hydrocortisone creams can be used. These creams are applied on the affected part of the skin to temporarily relieve itching. this option can be used on patients with PMLE or those with solar urticaria
- Phototherapy is the other treatment option for a patient with PMLE, it involves gradually exposing the skin to increased levels of UV light to treat the allergy.
The patient will begin to develop a tolerance to sun exposure thus reducing the symptoms.
- If a patient is not responding to phototherapy, the doctor may prescribe PUVA a combination of psoralen and ultraviolet light. This treatment option is common in patient with hereditary PMLE or classic PMLE.
- Supplements containing oral beta-carotene can also be used to treat the allergy and get rid of the symptoms.
Home remedies for sun allergy
For mild cases of the rash, simple self-care and natural home remedies will help relieve the rash and soothe the symptoms. Some of these steps include the following:
a) Avoiding exposure to the sun
For most people, the symptoms of a sun allergy improve quickly. A sun allergy rash will often clear within a day or two, for some people the rash will even clear within an hour or two.
For those with sensitive skin, we recommend you avoid excessive exposure to the sun. If you have to spend a lot of time outside, then make sure to cover your skin properly. Apply some sunscreen to reduce the penetration of UV rays.
b) Apply a moisturizer
There different brands of skin moisturizers that can help relieve the irritation and keep your skin moisturized. Moisturizing gel and creams prevent your skin from drying, peeling or cracking which can be made worse by a sun poisoning.
c) High UV locking sunscreen
A sunscreen is a cream or lotion rubbed onto the skin to protect it from the sun. There are also known as sunblock or suntan lotion. These creams work by absorbing or reflecting some of the sun’s UV radiation which helps protect against sunburn.
d) Calamine lotion
Calamine lotion is also known for its great soothing and cooling effect. It can be used to treat itching and mild skin irritations, it a great home remedy for sunburned skin.
Gently apply the lotion on the skin after applying a cold compress on the affected part of skin.
e) Aloe Vera Gel
Like calamine lotion, Aloe Vera is the other effective remedy you can try at home. It is a natural anti-inflammatory and anti-itching remedy that will help soothe the itch and relieve the inflammations caused by sun allergy.
When using any of the above remedies, discontinue their use if you develop symptoms of a skin reaction. This includes such things as increased redness, a rash, severe itching and skin inflammations. We recommend you seek immediate medical care.
Sun allergy prevention
Preventing the symptoms or this form of skin allergy involves protecting your skin to exposure to sunlight. To do that, we recommend you try the following:
- Before going out, make sure to apply a sunscreen that has a high sun protecting factor (SPF). We recommend that of SPF above 15 with a broad spectrum of protection again UVA and UVB rays.
- Limit your time outdoors especially when the sun is at its peak.
- To protect your eyes, wear sunglasses with UV rays protection.
- On your lips, we recommend a sunblock formulated specifically for the lips, it should have SPF of more than 20
- If you have to spend a lot of time outside, wear long sleeve shirts, long pants and hat with wide brim
- Have your dermatologist or healthcare provider recommend skin care products and medicine that do not trigger photoallergic eruption
- Sun allergy (photosensitivity): https://www.health.harvard.edu/allergies/sun-allergy-photosensitivity
- Sun allergy meaning: http://www.mayoclinic.org/diseases-conditions/sun-allergy/basics/definition/con-20035077
- When it is not a sunburn but a sun allergy: http://www.refinery29.com/sun-allergies
- Does sun allergy exist: https://www.verywell.com/sun-allergy-symptoms-83211
- Lifestyle and home remedies for sun allergy: http://www.mayoclinic.org/diseases-conditions/sun-allergy/basics/lifestyle-home-remedies/con-20035077