Before a root canal opening, that first removes the decayed tooth structure and opens the tooth, there are no prerequisites. An adequate medical history will have addressed any specific issues that might problematic to the treatment. If so, follow and specific directions.

Most medications and those such as blood thinners, aspirin will have little or no effect on the treatment. If there would be a conflict between your meds and the treatment, this will be addressed prior to the procedure. Follow those instructions. You should not be taken off any anticoagulants (blood thinners). There is a higher and significant risk of clot formation in patience taken off anticoagulants.

Afterward, if the infection is significant, the tooth may be left open to drain. In this case, you will be instructed to chew elsewhere and avoid filling the hole with food debris. Ideally, you may have a temporary filling to close the access point and cover the removed carious tooth structure. You should avoid chewing on that tooth to keep the temporary filling in tact and the canal sealed from the fluids in the mouth.