Hi and welcome to Healthcaremagic. Thank you for your query. I am Dr. Rommstein, I understand your concerns and I will try to help you as much as I can. No, these antibiotics wont kill pinworms but also your symptoms may not be related to pinworms. It may be caused by hemprrhoids or anal fissure so you should see proctologist for further actions. Pinworms can be treated with metronidazole if proved so you need to do parasitic stool analysis. I hope I have answered you query. If you have any further questions you can contact us in every time. Kindly regards. Wish you a good health.