You should try posting in the expats forum - you would get a better response there i would imagine

You should also try the search facility - there has been a few threads on healthcare in Turkey

Cheers

LA

they will need private medical insurance either from home or from one of the health insurace companies operating from most of the big banks here. Yapi Kredi for example. insurance in Turkey is called Sigorta.
The Devlet or government hospitals have low charges but are not very good . Best to be avoided. The private sector hospitals are excellent and treatment is much cheaper than the equivalent in the uk.
For prescription drugs they will have to get a 'recete' or script from a local doctor or hospital. The costs of the Drs services can be reclaimed.
Although many drugs can be obtained at the chemists (eczane) these are mostly antibiotics, tummy upsets, allergies, birth control Hrt and mild analgesics.
there is a sytem here whereby poor people can get a green card which gives then free care but it isn't easy to get the card and involves a lot of beaurocracy.

Craig
You don't say where they are going to but most of the bigger towns have reasonable private medical facillities. Like Shirley said the government or Devlet hospitals are a bit variable to say the least. Its a good idea to shop around for medical insurance in UK and here as the prices vary wildly. I use Yapi Kredi bank for my family and have found them to be good on paying Up also as we live in Antalya we use the university hospital which I have found to be good and well organised. Also like Shirley says the chemist can supply a lot of drugs off prescription so to speak but you may need to find a doctor for a prescription here, so it would be a good idea if they come out with enough pills to go through the first few weeks at least. One company in Uk that does cover long term visitors here is travelsafe and you can get them via info@vikinginsurance.co.uk I dont know what they are like but one of my expat friends uses them.

All the best with it all.

In Turkey imported drugs are expensive, the ones they make aren't. they are as good or better than the imports. medical insurance might not cover an existing condition so beware.
In marmaris there are 2 private hospitals, both excellent and a state hospital which is OK but can be chaotic.
research your medical requirements very thoroughly before you come over.