Treatment For Swimmer's Itch - Cercarial Dermatitis

Updated September 16, 2023

As the summer months continue to get hotter, more and more of us are finding relief from the heat by taking a refreshing plunge in a pool, lake, or even the ocean. However, if you wind up swimming in either fresh or salt water that is home to a specific parasite, you may develop more than a good workout. You may develop Swimmer’s Itch, a skin rash also called Cercarial Dermatitis.

In basic terms, the parasites responsible for Swimmer’s Itch come into contact with you in the water, burrow under your skin and cause an allergic reaction, resulting in an itchy rash. Symptoms of swimmer's itch may include crimson bumps, itching, small blisters and a burning sensation that can range from mild to severe.

Although there is no true cure for the condition, much is known about treatment and prevention, meaning the symptoms can be managed and mitigated. As with so many skin conditions in which an itch is a known problem, scratching may cause the rash to become much worse, and potentially lead to more severe symptoms like bacterial infections. Luckily, itching can be relieved with fast acting, effective over-the-counter medications like Dermeleve®.

Since it’s caused by an allergic reaction, Swimmer’s Itch is not contagious, and it will eventually disappear by itself within a week or so without treatment. However, it may last longer in certain instances; and in those cases, may require special treatment for swimmer's itch from a doctor who may recommend a prescription.

In this article, we’re going to dive deep (pardon the pun) into Swimmer’s Itch. What is it, what are the symptoms, how to prevent it, and how to treat it.

What Parasite Causes Swimmer’s Itch?

Swimmer’s Itch is caused by a particular parasite that can be found in bodies of fresh water, such as pond or lake water; as well as salt water, like the ocean. This parasite lives in the blood of birds such as ducks and gulls, as well as land animals like muskrats and raccoons that live near water. These parasites produce eggs, which are expelled from the body of the bird or mammal in its excrement.

These eggs can hatch in water, releasing microscopic larvae which swim in the water looking for a specific type of water snail. Once a host snail is infected, a new type of larvae called cercariae is released from infected snails. Like its predecessor, cercariae begins looking for a goose or other aquatic bird or mammal host to repeat the cycle. Though humans are not the intended hosts, they can become infected as well.

When swimming in infested water, the larvae of the parasite can dig into your skin, triggering an immune response in your body. Once the body has an allergic reaction to certain conditions, discoloration, itchiness and irritation of the skin can follow. These parasites quickly expire after penetrating the skin since the larvae cannot survive in the human body.

The irritation can continue for a couple of weeks, but it generally goes away within a few days.

What is the appearance of the swimmer’s itch rash?

Cercarial dermatitis, also known as Swimmer’s Itch, is named after the cercariae parasite that infects the human skin, causing an allergic reaction. It usually resembles a raised rash, accompanied by colored bumps or acne. Additionally, it could itch, burn, tingle or cause the skin to blister. Only skin which has been directly in contact with the infected water will develop swimmer’s itch, and this can occur immediately or up to several days after swimming in contaminated water such as lakes and ponds.

How widespread is swimmer’s itch?

Swimmer's itch is a known risk to those swimming in fresh or salt water; though it is more frequent to contract cases in fresh water such as ponds and lakes, as opposed to salt water like the sea.

Who is most at risk of catching Swimmer’s Itch?

Any person that is in infected water is susceptible to developing the condition; though the parasite is more likely to be found in shallow waters. Small children are more likely to get Swimmer's Itch since they tend to play and swim in shallower water.

What parts of my body can develop Swimmer’s Itch?

Any direct contact with contaminated bodies of water can result in Swimmer’s Itch. This means that the itching and rash may appear on any part of your body, as long as that part of your body was in the water with the parasite that causes the condition. It is common for Swimmer’s Itch to occur on the legs, as they are most often the part of the body submerged below the surface of the water, from walking and wading to swimming.

Is Swimmer’s Itch considered contagious?

Cercarial Dermatitis is not communicable. In other words, you cannot transfer it to another person or acquire it from someone else. The only way to get a skin rash caused by this parasitic condition is to have the larvae burrow into your skin directly.

How is Swimmer’s Itch diagnosed?

Diagnostic tests to identify Cercarial Dermatitis are not available at the moment. Given that the itch is an allergic reaction that resembles that of other skin disorders like poison oak, this skin condition may be challenging to diagnose. Keep in mind that swimming in either fresh or sea water can also cause other rashes besides Swimmer’s Itch.

What are the treatments for an itchy rash caused by Cercarial Dermatitis?

Cercarial Dermatitis does not have specific medical treatment options compared to a rash caused by an allergic reaction to any other cause. It normally disappears after about a week.

The key to treating Cercarial Dermatitis is to try not to scratch it. Even though the itching is severe and scratching may be the only thing on your mind, it can only make it worse. Scratching can cause the itching to intensify, as well as lead to the rash to become infected from skin cracks caused by excessive scratching.

For immediate relief of the itching, the use of a fast acting, non-steroidal anti-itch cream like Dermeleve® is recommended. Not all anti-itch creams are created equal. It’s important to make sure that you understand the risks of using products that contain corticosteroids before using them.

Other Home Remedies to Treat Swimmer Itch:

• Using a cold compress on the irritated area.
• Soaking in a colloidal oatmeal bath or Epsom salt baths.
• Treating the area with a paste of baking soda mixed with water.

If symptoms persist, it’s best to seek medical attention from your doctor or health care provider.

How long will the symptoms of Swimmer’s Itch last? 

Cases of swimmer’s Itch typically last for several days, but usually disappear within about a week. However, the length of symptoms could increase; particularly if you have repeatedly or daily swum in the infected water. The rash may require medical attention if it lasts for more than fourteen days or if the blisters are oozing pus. 

How can I avoid catching it?

To lessen your chances of developing Swimmer Itch, you can:

• Rinse off with clean, fresh water immediately after you finish swimming, to remove any residual salts.
• Make sure to thoroughly dry off with a fresh towel.
• Carefully consider where you will swim. Aim to avoid swimming in areas where Swimmer Itch has been known to occur. Keep an eye out for indications near the swimming area that could alert you to potential contamination, such as signage that has been posted warning of unsafe water.
• Avoid feeding wildlife close to where you swim: The parasite responsible for Swimmer’s Itch can be found in animals that reside close to either freshwater or saltwater. You don’t want to entice them closer to swimming areas since they might transfer parasites there.
• Avoid swimming or wading in or close to marshland: Snails prefer marshy areas near water, and they can often harbor the Swimmer’s Itch parasite.
• Avoid shallow water swimming or wading if at all possible: The swimmer’s itch parasites can frequently be found near the coast or in low level water. If you are an experienced swimmer, swim in deeper waters in order to avoid the parasites.

When would a doctor appointment be recommended?

Swimmer’s Itch typically doesn’t require medical care. Itching that is particularly severe may require you to use a more powerful anti-itch product prescribed by your doctor once they diagnose swimmer's itch.

If you have a rash lasting longer than fourteen days or blisters oozing pus, your rash may require treatment. Your health care provider may recommend prescription lotions or creams, or over the counter remedies such as anti-itch products like Dermeleve®.

Can my swimming pool cause Swimmer’s Itch?

Swimmer’s Itch cannot be contracted in regularly maintained pools that receive chlorine treatment. Additionally, the specific type of snails that host the parasite must be present for the risk to exist.

Can it spread to additional body parts?

Only parts of your skin that have come into touch with contaminated water can develop Swimmer’s Itch. As a result, it stays localized to the allergic reaction’s original site.

However, you might get multiple sites of a rash on your body, if you swam in infected water multiple times over the course of a few days.

If Swimmer’s Itch is detected, will that water always be infected?

No. Since specific animals, including snails, must all be present for Swimmer’s Itch to become an issue in both fresh and salt water, several different elements must come into play. Because of this, it’s possible Swimmer’s Itch won’t be a consistent issue in a contaminated swimming location, as these conditions are changeable.

However, there's no way to know how long duration of contamination is. Prior to entering either freshwater or saltwater, always check for signs that indicate potential Swimmer’s Itch contamination.

Wrap Up

So there you have it. Swimmer’s Itch is the annoying, itchy, rashy Summer best friend you never knew you hated. Keep in mind that while Cercarial Dermatitis is a bothersome condition, it is not dangerous and the symptoms can be managed.

The most important thing to remember is to resist the urge to scratch the itch, as this can cause the rash to become much worse. We know better than most the battle that is fighting the urge to scratch. That’s why we’ve created the best secret weapon you could have; to not only win the battle, but the whole war. Dermeleve® is immediate relief anti-itch fire power that’s got you covered (or at least wherever you’ve covered yourself with it, but you know what we mean).

With proper care, and no scratching, the symptoms of Swimmer’s Itch can be relieved and the condition will eventually go away. And you can get back to the important things, like swimming (or, in our case, defined as drinking a Mai Tai from an inflatable flamingo floaty).

Visit the Dermeleve® website to learn more!