<s>[INST] Hi- I had to have a root canal REDONE on monday- and have had a very bad toothache since- I called the doc on wed. and he said to keep taking the clindamycin and it should get better- its now thurs morning and its still one pumping toothache - the kind that will not let you sleep- how long till these meds kick in or is something else going on here? [/INST] Thanks for your query, I have gone through your query. The pain could be because of the tooth infection or endodontic flare up that occurs following root canal treatment. Usually it will come down in 3-4 days. Instead of clindamycin you could have taken combination of penicillin 500 mg TID and metronidazole 400 mg bid for 5 days course. Do saline gargling, if the pain does not subside then consult your dentist. I hope my answer will help you, take care. </s>