Your dentist needs to know about all the medications that you are taking, any allergic reactions you've had to medicines in the past, and your past and present health conditions. It's important that you answer your dentist's questions completely and ask about your concerns. This way your dentist will be sure to tell you everything you need to know before receiving treatment. For example, in some cases, your anesthesia treatment may require that you suspend certain medications or abstain from eating or drinking for a period of time before the treatment.