For any future visa questions, it’s important to state your nationality. There are different rules for different nationalities. Visa-on-Arrival (VOA) is different from Visa-Exempt.
The site is a collaboration between the Thai FDA, Narcotics Control, and Ministry of Public Health. Enter details, select name(s) of meds, get the answers. If any of them are, follow the instructions to apply for a permit to bring them into the country. Typically, you receive your permit in 2-3 days.