500mg amoxcillian taken after 3 tooth extractions. prescription says take 4 times a day, but shouldn't there be an 8 hr interval in between?

You're right: Usually For a 500 mg dose, It is 3 times a day or every 8 hours, morning, mid day and dinner. If prescribing 250 mg dose then the frequency is 4 times a day. Call your doctor to be sure.

~every 6hrs: It doesn't have to be exact if the frequency is too much for u. U could ask ur doctor to change the dosing for u

500 mg TID X 1 week: For severe infections or after "hot" tooth extraction the dose for adults is 500 mg amoxicillin three times per day for a week. To get prompt results, make sure that the prescribed medication course is completed. There is no benefit to take amoxicillin 500 mg 4 times per day.