Threadworm

Q) Our whole family has been plagued by threadworm for more than four years now. We have tried everything to no avail, and it’s taking its toll on our overall wellbeing. We have had courses of wormwood, cloves, black walnut, garlic, raw carrot, apple and pumpkin seeds, Biocidin/grapefruit seed extract, probiotics, homeopathic Cina and Baryta Carb, Echinacea, zinc, copious handwashing, morning bottom-washing—the list goes on. We are somewhat limited as to what we can try by the age of our children, although the youngest is now two. My husband routinely uses over-the-counter mebendazole, following up two weeks later, but it does little more than stop the itching for a while. The only thing that seems to keep them at bay is garlic oil on the anus at night, but we would like to be rid of them altogether.

Can you help?—A.C. Oxon

 

A) Threadworms are thin white worms only a few millimetres long. Also called ‘pinworms’ because of their tiny size, their official name is Enterobiasis vermicularis, which gives a clue as to where they live—

in the large intestine. Humans are thought to be their only carriers.

It is probably the most common human parasite, affecting an estimated 14 per cent in the US, and a staggering 50 per cent in England (Int J Dermatol, 2005; 44: 837–40). It appears to be no respecter of social class—anyone can get it—and is relatively harmless, although it can cause stomach pain, anorexia and even appendicitis. The most common symptom is anal itching that is usually worse at night, as that’s when the female threadworm comes out of the anus to lay her tiny eggs in the folds of the anal skin, adhered by a sticky white substance.

The worm usually returns to the intestines in the morning, but it sometimes gets lost; if it enters the vagina, it can cause localized irritation and discharge, but also endometriosis, pelvic inflammatory disease or kidney infection. If the worm gets into the bladder, it can cause urinary tract infections and urination problems.

As the worm rarely shows up in stool samples, the most effective diagnosis is to use sticky tape on the anal area to pick up the worms or—more likely—their microscopic eggs. The test is best done just before getting up in the morning.

The conventional treatments are drugs. Mebendazole, the one your husband has used, is probably the best known and claims to be 76- to 95-per-cent efficient. However, it’s toxic to the fetus (Drugs, 1997; 53: 769–88), so don’t use it if you’re planning on being pregnant again. Other common adverse effects include stomach upset, loss of appetite, diarrhoea, fever, headache, dizziness, drowsiness or rash. Rarer side-effects are jaundice and hepatitis, showing up as dark urine and yellowing of the eyes or skin. The drug can also cause severe allergic reactions.

Pyrantel pamoate is another drug option. Marketed as Pin-Rid, it is meant to be taken only once, perhaps because of its side-effects: skin rashes, abdominal cramps, diarrhoea, nausea or vomiting, headache, dizziness, drowsiness and insomnia. It’s thought to act by paralyzing the worm, causing it to lose its grip on the gut wall and allowing it to be flushed out. But the drug doesn’t affect the larvae or eggs, so repeat doses are needed, a course of action not advised by the US Food and Drug Administration and allowed only with medical supervision (US Pharm, 2006; 12: 10–5). The take-home message: beware of Pin-Rid.

A third drug is albendazole (Valbazen), which has side-effects similar to those of mebendazole; it’s also not suitable for young children.

As for alternatives, you’ve already discovered the wide range of herbal and dietary options. However, as they’ve not worked for you, you may wish to go back to basics—in a word, hygiene. A recent survey of the homes and schools of infested children found viable threadworm eggs on or in a variety of sites—soap, pet fur, swimming pools, school dining-room walls and house dust (Diabetologia, 2002; 45: 588–94). Clothes, bedclothes and carpets are the most common locations, however.

So, try an intensive, high-hygiene regime. Every day, vacuum the floors, put fresh sheets on the beds, replace towels, and wear clean underwear and close-fitting nightwear. Have a daily shower (rather than a bath), paying particular attention to the anal area. A bidet is even better, as the eggs are easily flushed off with water. Scrupulous hand hygiene is mandatory, and it will help if everyone’s nails are trimmed to prevent the eggs lodging beneath them. Prevent the children from scratching their bottoms, as that’s a common route of cross-infection. Give them cotton gloves at night in case they scratch in their sleep.

There’s also homeopathic Borax, which you may not have tried, and herbs such as myrrh and guggul. An Ayurvedic herbal practitioner will be able to help.

A diet high in olive oil may also prevent the worms from settling into the gut. Besides garlic oil, creams made of lavender balm, zinc or castor oil applied externally can prevent the eggs sticking to the skin. 

Finally, you could also try an enema of the tree-herb Picrasma quassioides (nigaki). Use 2–4 mL of freshly prepared infusion, mixing it with cold water at a ratio of 1:20 on three successive mornings (British Herbal Pharmacopoeia, Part 2. W Yorks: British Herbal Medicine Association, 1979: 137–9).