Dr Phil Kieran: My teenager got scabies on a camping trip

Unfortunately, the itch can take four to six weeks to settle, but in the meantime you can use antihistamines and plain moisturisers to help relieve it. Picture: iStock

My 15-year-old son picked up scabies while on a school camping trip. I’ve applied all the lotions and disinfected his clothes and bedding. But it hasn’t cleared up. The itching is as intense as ever. He’s usually an outgoing boy, but the rash is making him very self-conscious. Is there anything else I can do?

Scabies is one of those words that makes people itch just to hear it. Any family going through scabies eradication has my deepest sympathy. For your own son, the good news is that the treatment — if done correctly — was probably effective, and the itch will go away. 

Unfortunately, the itch can take four to six weeks to settle, but in the meantime you can use antihistamines and plain moisturisers to help relieve it.

Most of the time, I explain what is going on before giving advice, but with scabies, the itch is so intense that people just want to know what to do to relieve it.

Often, the itch is manageable during the day, but at night it can become intense and all-consuming. Worse is when it finally goes away, people are terrified that every time they feel an itch, it is the scabies returning.

Scabies is caused by a tiny mite called Sarcoptes Scabiei. This mite burrows into the skin and lays eggs before dying. The eggs then hatch and migrate to the skin surface to mate, and then the cycle begins again. This whole cycle lasts about 11 weeks. 

It isn’t the burrowing that causes the itch — though it does contribute to the rash; the itch is caused by the dead mites or their excretions, causing an allergic-type response in the skin. The immune system response triggers the intense itch. 

This is why the itch takes so long to settle after treatment. The itch will persist until the layer of skin the mites were inhabiting is shed and replaced.

The lack of immediate improvement can lead people to think the treatment was ineffective, and, unfortunately, excessive treatment can itself cause itching and skin irritation.

When scabies is diagnosed, it is important to treat not only the person with it but all household contacts. 

The treatment is available over the counter, and it’s called permethrin. 

It should be applied before going to bed over the entire skin except the face and scalp. Imagine drawing a line along the hairline on your neck below your ears, and along your jaw — everything from here down needs to be covered in cream.

It is particularly important to cover the webs between your fingers and toes, as well as all body creases. Scabies preferentially settle in the skin between digits and in skin creases in the groin or buttocks. 

I advise that, where possible, you have someone else apply the cream on your back to ensure full coverage.

You should wash the cream off the next morning — after about eight hours — then wash the clothes you were wearing the day before, and wash all the bed sheets at a high temperature. 

Anything that can’t be laundered — eg, teddies — should be placed in a plastic bag and left in a cupboard at room temperature for at least 72 hours. This will starve and kill any mites.

It is recommended that everyone in the household repeat the treatment after seven days. By following all the above guidelines, treatment is almost always successful, and ongoing infection usually results from either not everyone being treated or the skin not being fully covered with the medicated cream or lotion.

True treatment resistance is thankfully rare, but if you think you have done everything right and the rash is still progressing or new burrows are visible, then you should see your GP to discuss other treatment options.

It is important to let your son know that he won’t be left with this rash forever, and the itch will pass. I strongly recommend an antihistamine for the itch, which will allow him to sleep better and make everything seem less difficult.

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