Threadworms are tiny white worms that infect your large intestine. Whilst they’re harmless, they can cause extreme itching, especially at night when the female worms come out to lay their eggs.
Threadworms are often common in children, especially those that regularly share toys or forget to wash their hands. The eggs are transferred in several ways, and they can be swallowed, inhaled, or just transferred directly to your skin without you realising it.
Sometimes, you won’t experience any symptoms of threadworms, but you’ll usually be able to see them in your poo, bedding or underwear. They’re treated with a single dose of mebendazole alongside strict hygiene standards.
Below are some common Threadworm medicines. Please note, this is not an exhaustive list and other non-medical methods may be more suitable. If you would like to learn more about these options, then please click here. Before receiving medication you must answer a number of questions to asses your suitability. All questions are reviewed by a GMC registered doctor before a final decision is made. All medication is dispensed via a full regulated and registered UK pharmacy. All medication is dispensed via a full regulated and registered UK pharmacy. All prices displayed on our site include the price of the medication and our doctors consultation fee.
Our Health Care Team
"Threadworms are usually seen in children, but anyone can be affected by them. Practicing good hygiene and thorough cleaning can reduce your risk of contracting the infection, but sometimes, it’s completely unpreventable. Treatment is easily available and often only needs a single dose to kill the worms in your intestine."
What are threadworms?
Threadworms (also called pinworms) are tiny worms that are often found in your faeces.
Their name is down to their appearance, as they look like small pieces of white thread.
Threadworms (enterobius vermicularis) are most common in children, but anyone of any age can experience them, with the large intestine being affected.
The condition isn’t harmful, and is very rarely a cause for concern, but it can be extremely irritating, especially if severe itching is experienced.
What are the symptoms of threadworms?
Threadworms sometimes don’t cause any symptoms, but if you’re infected with them, you’ll likely experience:
- Extreme itching around the anus
- Waking through the night
- Weight loss
- Bed wetting
- Irritated anus
Some of the above symptoms are more common than others, and in girls and women, if the infection goes untreated for some time, the worms can also make their way into the vagina, causing it to be inflamed and often sore or uncomfortable.
You might find that you’re itching more at night, as this is when the female worms come out to lay their eggs. These are normally laid around your anus and any surrounding surfaces and materials, such as towels, bedding, underwear and nightclothes.
Part of the itching may also be down to the female worms releasing mucus which can irritate the skin.
You may be able to see threadworms in your poo or sometimes in your bed or underwear. They can often be seen wriggling, and the female worms are most likely to be spotted as these are the oens that make their way out of the intestine to lay their eggs. Threadworms are usually up to 13mm long and white, resembling a small piece of thread.
What causes threadworms?
Threadworms are spread by poor hygiene. They’re more common in children due to the fact that they sometimes forget to wash their hands and then go on to share toys with their friends. However, adults are often affected by them too.
If you accidentally swallow any threadworm eggs, you’re likely to be infected with them as they hatch in your large intestine. The eggs can be transferred in a range of ways. If they become airborne from shaking a towel or bedding that they’re on, they can easily be inhaled, and due to their microscopic size, it’s often extremely difficult to tell where they are. The worms are spread further if good hygiene isn’t maintained, and are transferred to other surfaces when you’ve scratched your anus.
Finally, the eggs can be transferred if you share towels or bedding with someone that’s already been infected, as they stay on the material and then get stuck to your skin until they hatch.
How are threadworms treated?
Luckily, the treatment of threadworms is quite straightforward. Usually, you’ll be prescribed mebendazole to remove the infection, which often only requires a single dose. Everying in your household should be treated for the infection, even if nobody else is showing symptoms, as the risk of transferring the eggs from one person to another is high once someone already has it.
Alongside the medication, it is recommended that you practice strict and rigorous hygiene for 2-6 weeks after taking the medication, as the eggs can survive for up to a fortnight after they’ve been laid. Mebendazole will only kill worms that are already living inside the large intestine, but unfortunately, it won’t kill any eggs that have been laid around your anus or on surrounding areas and materials.
It is recommended that you regularly wash your hands, especially after every visit to the toilet, and before meals. You should also change your underwear daily and wash all towels and bedding that you used whilst infected. You should also thoroughly clean each room in your house, especially the bathroom and kitchen, whilst making sure to shower or bathe every morning to make sure that any residual eggs are washed away.
How do you prevent threadworms?
Unfortunately, threadworms can’t always be prevented, especially if you have young children in your house, but encouraging good hygiene and reminding little ones to wash their hands regularly is a great start to preventing any kind of infection.
Regularly washing any laundry, towels and bedding will reduce the chances of any eggs being transferred, but if you do still get infected, the treatment is often simple and the worms usually die from one dose.
What if I can’t take mebendazole?
If you can’t take mebendazole for any reason (perhaps you’re pregnant or breastfeeding), your octor may suggest 6 weeks of rigorous hygiene as an alternative method of removing the worms. Whilst this means you may experience symptoms for longer, it is usually a safer option for expectant and new mothers.
If you have a child under the age of 2, and either you or them are infected with threadworms, please make an appointment with your GP who can suggest different treatment methods.
Will threadworms come back?
It is possible to experience threadworms more than once, but if you keep up with good hygiene and encourage others in your household to do the same, your risk of recurring infection will be lowered considerably.