Noticed Small White Worm Moving On Bottom. Suffer Itching. Prescribed Mabendazole. What To Do?

Posted on Mon, 30 Sep 2013

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Mon, 30 Sep 2013 Answered on

Thu, 24 Oct 2013 Last reviewed on

Question : Hi, my son has had what i think is pinworm i could see XXXXXXX at night a small white moving worm on his bottom just 1 or 2cm long thin round white. He has gad a very itchy bottom. I have given him pyrantel a few months ago 2 doses 2 weeks apart and it seemed to work itchibg stopped. But then came back recently so i gave another dose but its been 5 days and he is still itchy is it possible its not working on him. What would you advise. I though to perhaps try mebendazole but how long before i can try a dise of that after pyrantel dose. Also gaving him shower twice a day and washing linen daily etc.

Answered by Dr. Dr.P.Ratnakar Kini (8 hours later)

Brief Answer:
Detailed answer given below

Detailed Answer:
Hi,
Thanks for posting your query.
I am Dr.Ratnakar Kini and I am pleased to assist you.

If there is recurrence of symptoms, then you can give one course of mebendazole. There is no specific time limit you need to wait after giving pyrantel pamoate.

I would suggest that all the family members be treated simultaneously with deworming medication even if others do not have any overt symptoms.

In addition to washing his linen, also cut his nails.
Let me know if I can assist you further.
Regards,
Dr.Ratnakar Kini

Above answer was peer-reviewed by : Dr. Vaishalee Punj

Follow up: Dr. Dr.P.Ratnakar Kini (16 hours later)

Could you tell me:
1. Is it possible the pyrantel is not working to kill pinworms
2. How long should pyrantel take to stop itching
3. How long does pyrantel paralyze worms for or is it permanent paralysis until they are pooped out

Answered by Dr. Dr.P.Ratnakar Kini (5 hours later)

Brief Answer:
Detailed answer given below.

Detailed Answer:
Hi,
Thanks for contacting me with more questions.

1. Pyrantel pamoate is very effective against pinworms. But reinfection is common and young pinworms may be resistant. Hence three doses at 3 weeks interval should be given for complete eradication

2. Pyrantel pamoate does not stop itching. It only eradicates the worm. Once the worms are eradicated, the itching due to worms resolves.

3. It paralyzes the worm for about 12-24 hours.

Let me know if I can assist you further.
Regards,
Dr.Ratnakar Kini

Above answer was peer-reviewed by : Dr. Vaishalee Punj

Follow up: Dr. Dr.P.Ratnakar Kini (15 hours later)

Hi, you said it paralyzes wirms for only 24-48 hours which didnt sound correct to me or the drug wouldnt work. I called the drug manufacturer and tbey said it permantky paralyzes them. Also looked on internet and said same. Could you give me a link to evidence you are correct?

Answered by Dr. Dr.P.Ratnakar Kini (4 hours later)

Brief Answer:
Detailed answer given below.

Detailed Answer:
Hi,
Pyrantel pamoate cause depolarizing paralysis. The bowel movement eliminate the paralyzed worms .
The manufacturer must be correct (than the reference I know) in saying they cause permanent paralysis.
But irrespective of whether it cause permanent or temporary paralysis, all you need to know is take the medication in three doses at 3 weeks interval.

Let me know if I can assist you further.
Regards,
Dr.Ratnakar Kini

Above answer was peer-reviewed by : Dr. Chakravarthy Mazumdar