Doctors can be found listed in the Yellow Pages , and ambulance services are usually displayed on the inside cover. In emergencies call 911. If you are bringing medicine prescribed by your doctor, bring a copy of the prescription ; first, to avoid problems at customs and immigration and, second, for renewing medication with Canadian doctors. Pharmacies are often well equipped to advise on minor ailments and to distinguish between unfamiliar brand names. Most larger towns and cities should have one open 24 hours, and many chemists stay open late as a matter of course.