Thank you for your question and welcome to Just Answer. I am sorry you have a tooth infection. Here is what I recommend:
Macrobid is an antibiotic used to treat urinary tract infections. The bacteria that Macrobid is effective against is not usually the same bacteria that infects the teeth and gums and probably will not be effective for your toothache. The antibiotic of choice for tooth and gum infections is either Amoxicillin or Clindamycin if you are allergic to Amoxicillin. Call your dentist and see if he can call you in a prescription for one of these today until you can get in to the clinic and have the situation taken care of. Antibiotics usually take between 36 and 48 hours to become clinically effective so try to get started on those today if you can. I hope this answers your question.
If you have any concerns regarding this issue that I have not addressed, please let me know and I will get back to you with more information.
Sincerely, XXXXX XXXXX DDS
Your are most welcome. I wish you well.
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