Shortly after being stung, a swimmer may complain of skin discomfort. The rash develops in a few minutes to 12 hours after swimming. The rash consists of raised, hard or soft bumps, or blisters of different shapes and sizes that appear very red and may be extremely itchy. The larvae can become trapped in the fabric of a swimsuit, under swim caps and fins, and along the cuff edges of wet suits and T-shirts. The rash often appears in areas of the body that were covered.
Thimble jellyfish and Sea anemone are usually the offenders. While sea lice normally goes away within two weeks without medical treatment, there are suggestions for how parents can treat their children at home. To see the recommendations, read more.
- Do not rub your skin. If larvae are on your skin, rubbing will cause them to sting.
- Remove your swimsuit as soon as possible. Since larvae can become trapped in the fabric of your suit, it is important to remove a contaminated suit to prevent more stings. If possible, rinse your suit in household vinegar or rubbing alcohol. Wash your suit in hot, soapy water and dry it in a dryer, if possible, before you wear it again.
- Shower with fresh water. Apply soap and vigorously scrub your skin. Do not shower with a contaminated suit on. If larvae are trapped in the fabric of a suit, a freshwater shower will cause the larvae to sting.
- Take an antihistamine, such as diphenhydramine or chlorpheniramine, or apply hydrocortisone cream (1 percent) to help control itching. Note: do not use the cream on children younger than age 2 unless your doctor tells you to. Do not use in the rectal or vaginal area in children younger than age 12 unless your doctor tells you to. Also, don't give antihistamines to your child unless you've checked with the doctor first.
- Use an ice pack to help relieve pain.
- Keep the rash clean. Wash it every day with soap and water.