While you will have access to all the services you had at home in any major Turkish city, expect the quality of these services to vary wildly depending on the provider.
Pharmacies (eczane) are widely available in Turkey, though Turkish pharmacy culture is probably different from what you remember from home. For one thing, many Turkish pharmacies offer medication over the counter that is only issued by presciption in other countries. In addition, large pharmacies may offer vaccinations and other basic medical services.
In general, you should not have difficulty obtaining any medication you require while living in Turkey. If a Turkish pharmacist does not have a particular type of medicine in stock, he will probably be able to order it, even from abroad.
While large cities all offer 24-hour pharmacies, in small towns and villages you may instead find a designated “duty pharmacist“ (nöbetçi eczane) on call 24 hours a day. There will usually be a sign outside the local pharmacy indicating the current nöbetçi eczane. In very small towns, there may only be one.
Turkey is a pill-centric country. Don´t be surprised if a doctor writes you 3 or 4 prescriptions per visit. Chances are that you will get at least one prescription even if he has not made an official diagnosis. There are two explanations for this: Turkish culture places great faith in pharmaceutical treatment, and medical companies have been known to pay doctors extra to push their medications. Underpaid local doctors may be especially susceptible to the latter.
Don´t take all pharmacists´ recommendations at face value. While they are qualified, they will often try to sell foreigners the most expensive medication in stock. Though most insurance holders pay less than 20 % of their medication costs, the money can add up if you are filling multiple prescriptions. Always remember to check for generic medications, just like you would at home.
Dentists (diş hekimi) are available throughout all of Turkey. Most are well-trained, but the cheaper variety have sometimes learned dentistry through observation alone. This can make for ineffective (not to mention painful!) dental hygiene – go with a qualified dentist rather than cut corners. You will probably find dental care in Turkey cheaper than in your home country anyways.
The US Embassy offers a list of English-speaking dentists. This list also notes professional credentials and accomplishments where relevant.
Many foreigners coming to Turkey on “medical holidays“ are in the market for ophthalmologic procedures. The country has a reputation for expert laser surgery, to the point where some Turkish lasik surgeons now train ophthalmologists (gözlükçü) in other parts of the world.