6 Allergic Reactions While at the Beach

Sun, Sand, Water, Smoke, Insects, and Sunscreen

A sand rash or other allergic reaction at the beach can take some of the fun out of a day of sun and sea. The allergy may not only be due to substances you touch or breathe but also to things you may never have thought of, like sunscreen or even sunlight.

Insects like sand fleas can cause an allergic reaction to bites, while the sand itself may harbor pathogens and parasites that cause a rash, respiratory problems, and other symptoms.

This article explores some of the common and uncommon allergies you might experience at the beach and ways to prevent or treat them.

Family fun on the beach
Family fun in Mexico. Uwe Krejci / Getty Images

Sunscreen Allergies

Sunscreen is considered a must at the beach to reduce the risk of skin cancer. However, certain chemicals in sunscreen can cause a reaction in some people, known as allergic contact dermatitis. Symptoms include a red and itchy rash, often with bumps and blisters.

Reactions to sunscreen can be due to the active ingredients (e.g. oxybenzone) or due to fragrances or preservatives included in the sunscreen product. Oxybenzone also can react with chlorine if your beach day involves a pool, too.

For some people, the reaction to sunscreen only appears when they are exposed to both the sunscreen and the sun, and they would not react if sunscreen were worn in shaded environments.

You can reduce the risk of sunscreen allergy by purchasing a hypoallergenic sunscreen that contains fewer UV-filtering chemicals. There are also natural sunscreens that contain metal-based substances like titanium dioxide and zinc oxide that reflect light.

Sunburned man on beach
Tom and Steve/Photographer’s Choice RF

Allergies to Sunlight

A sun allergy is a relatively rare condition caused by exposure to the sun. It can cause itching, burning, stinging, and hives on sun-exposed skin. Also known as solar urticaria, a sun allergy usually develops quickly but can also go away quickly once you get out of the sun.

Some sun allergies have nothing to do with the sun. Instead, they are caused when basking in the sun causes the body to overheat.

Known as cholinergic urticaria, this form of allergy causes symptoms similar to solar urticaria but can affect covered parts of the body as well as uncovered parts. Cholinergic urticaria is now treated with Xolair (omalizumab), which tends to work better than antihistamines like Allegra (fexofenadine) or Zyrtec (cetirizine).

In rare cases, solar urticaria can cause a life-threatening allergic response called anaphylaxis that can't be treated with antihistamines. Because of this, it is usually recommended to limit your sun exposure if you have a history of solar urticaria. Talk with your physician about whether you need to carry an epinephrine auto-injector to treat anaphylaxis.

Sun Allergies and Medications

For some people, a heat rash or allergy symptoms happen due to certain medications. The sun exposure can lead to symptoms in people who take some antibiotics, nonsteroidal anti-inflammatory drugs (NSAIDs), and diuretics used to treat heart conditions.

This photo contains content that some people may find graphic or disturbing.

Poison Oak Rash
Poison oak rash.

Darren415 / Getty Images

Barbecue Allergies

A bonfire or barbecue can be part of the recipe for a perfect beach day. However, unless you know the exact species of wood you are gathering, you may end up exposing yourself to things like poison oak, poison ivy, or sumac.

These plants contain allergy-causing chemicals called urushiols when you touch them. But burning the plants also releases urushiols into the air, which can cause itchy blisters even if you don't touch them.

The itching and rash of contact exposure can be treated with cold compresses, topical lotions like calamine, and Benadryl (diphenhydramine). You also can try aloe or other home remedies.

Tree pollen allergies are common, too, and respiratory symptoms can occur after exposure or handling of birch or other woods. Consider calling 911 if you have chest pain, difficulty breathing, a swollen airway, or an altered mental status after exposure to the allergens or the smoke.

Swimming at Vancouver Third Beach in Stanley Park
© Randall Shirley

Allergies From Swimming

Allergies that occur after swimming are usually caused by organisms living in the water. These not only involve creatures in seawater but those in freshwater as well. :

  • Swimmer's itch is a condition caused by exposure to tiny parasites that live in freshwater. Also known as cercarial dermatitis, swimmer's itch is most likely to occur in places where there are a lot of aquatic birds or snails. Swimmer's itch causes an itchy rash that will generally clear on its own after several days.
  • Seabather's eruption (sea lice) is a different type of allergy that occurs when you come into contact with jellyfish larvae in the sea. The itchy rash usually occurs on covered skin, especially if you stay in a swimsuit a long time after leaving the water.

Because you usually don't know what microorganisms live in lakes or oceans, swimmer's itch and seabather's eruption can be hard to avoid. Rinsing off immediately after swimming can help reduce the risk. Calamine lotion or topical 1% hydrocortisone cream may help relieve the itching and swelling if you develop a rash.

Bee Sting
Silke Dietze/E+/Getty Images

Insect Allergies

Most insects are simply annoying, but some (like yellow jackets or bees) can be dangerous to those with a history of severe allergies. For these people, getting stung can lead to anaphylaxis.

Symptoms of anaphylaxis can come on rapidly after an insect sting. In addition to shortness of breath, facial and airway swelling, and an altered mental status, you may experience:

Anaphylaxis requires emergency medical care including the use of an epinephrine auto-injector. If left untreated, anaphylaxis can lead to shock, coma, suffocation, cardiac arrest, and death.

Thousands of sand fleas gathering.

arjanbestaatal/Getty Images 

Sand Allergies

Beach sand is a habitat for sand fleas, which typically cause itching and inflammation but it can also lead to an infection with black dots in the center of raised bumps, called tungiasis. In more severe cases, typically in developing countries, a tungiasis infection can cause gangrene, chronic pain, and permanent damage to the feet.

Fleas and sand flies (a different insect that can cause leishmaniasis) aren't the only possible cause of allergy or inflammation at the beach, though. Studies from Portugal, the United Kingdom, and Israel are among those detailing how bacteria, fungi, and other pathogens can thrive in beach sand.

Infections can include Candida auris, a treatment-resistant and potentially lethal fungal strain, and Aspergillus, Penicillium, and other molds that can lead to respiratory allergy symptoms. They are typically treated with antifungal drugs and allergy medications to relieve symptoms.

Summary

A day at the beach is something that everyone should enjoy. For some people, however, exposure to the beach environment can cause an allergic reaction.

This includes exposure to the sun (solar urticaria, cholinergic urticaria), water (swimmer's itch, seabather's eruption), and barbecue smoke (which can disperse allergy triggers into the air). Insect stings, sand, and sunscreen can also cause allergies.

Frequently Asked Questions

  • How can you prevent swimmer's itch?

    To help reduce your risk:

    • Don't swim in areas where swimmer's itch is known to be a problem or where signs are posted with warnings.
    • Don't feed birds around areas where people swim.
    • Rinse off immediately after swimming and dry off completely.
    • Avoid swimming or wading in marshy areas where snails can be found.
  • How can you relieve the symptoms of swimmer's itch?

    Try using an over-the-counter corticosteroid cream, bathing in Epsom salts, or using an anti-itch lotion. If the itching is severe, your doctor may prescribe a stronger lotion or cream, or an antibiotic if you have an infection.

  • How do you treat sea lice?

    Remove your swim clothes, gently pat your skin dry, and dress in clean clothes. To help relieve the rash, try using 1% hydrocortisone cream or topical calamine lotion. You can also use Tylenol (acetaminophen) or Advil (ibuprofen) for any discomfort.

14 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Daniel More, MD

By Daniel More, MD
Daniel More, MD, is a board-certified allergist and clinical immunologist. He is an assistant clinical professor at the University of California, San Francisco School of Medicine and formerly practiced at Central Coast Allergy and Asthma in Salinas, California.