Bringing OTC meds to Turkey

I will qualify this by saying just because it worked for me, doesn't mean it will work for you: I took all sorts of OTC meds to Turkey in non-original containers. I put them in small ziplocks and wrote the brand name, generic name, and dosage on the outside of the packet along with the expiration date. I wasn't asked about them. However it was not a lot of pills, so if you're bringing in quite a large quantity that could garner attention. If that's the case a doctor note might be useful if they're willing to write one.

For official Rx, you should have a doctor note and a copy of the prescription. You also might ask if they can print out separate labels you could affix to plastic bags to reduce the size of your bottle collection. From the US Embassy in Turkey:

37 Can I take my medication to Turkiye? Its recommended that you get a letter from your doctor stating you need the medication explaining
why you need to take it, the dose (amount) you need along with the
original prescription. The letter should be also in Turkish as some
customs officer may not speak English.

No one asked me at any time about my medications. Do they ask sometimes? I don't know, but it seemed not really to be an issue.

I've flown in and out of Turkey (Isyanbul) three times and my OTC and prescription meds have never been questioned. Neith have my husband's.