For medical advice and treatment, let your hotel (or if you’re camping, the closest farmacia) refer you to a good doctor, clinic, or hospital. Mexican doctors, especially in medium-sized and small towns, practice like private doctors in the United States and Canada once did before health insurance, liability, and group practice. They will come to you if you request it; they often keep their doors open even after regular hours and charge reasonable fees.
You will receive generally good treatment at the many local hospitals in Oaxaca’s tourist centers and larger towns. If you must have an English-speaking, American-trained doctor, the International Association for Medical Assistance to Travelers (IAMAT) publishes an updated booklet of qualified member physicians, some of whom practice in Oaxaca City [1], Puerto Escondido [2], and Huatulco [3]. IAMAT (1623 Military Road, #279, Niagra Falls, NY 14304, tel. 716/754-4883; or in Canada at 40 Regal Rd., Guelph, Ontario N1K 1B5, tel. 519/836-0102, or 1287 St. Clair Ave. W, Toronto, Ontario M6E 1B8, tel. 416/652-0137, info [at] iamat [dot] org or www.iamat.org [4]) also distributes a very detailed How to Protect Yourself Against Malaria guide, together with worldwide malaria risk and communicable disease charts.
For more useful information on health and safety in Mexico, consult Drs. Robert H. Paige and Curtis P. Page’s Mexico: Health and Safety Travel Guide (Tempe AZ, Med to Go Books, 2004) and Dirk Schroeder’s Staying Healthy in Asia, Africa, and Latin America (Berkeley, CA: Avalon Travel Publishing, 2000).
Links:
[1] http://www.moon.com/destinations/oaxaca/oaxaca-city
[2] http://www.moon.com/destinations/oaxaca/pacific-resorts/puerto-escondido
[3] http://www.moon.com/destinations/oaxaca/pacific-resorts/bahias-de-huatulco
[4] http://www.iamat.org