[actuator]

Aren't there psychoactive meds which weaken control and should work better unless the person has developed resistance against that compound.

[GuB-42]

There are, the most well known being alcohol.

However, while it makes people more talkative, it doesn't make them more truthful. So it is not considered effective as an interrogation technique.

[formerly_proven]

Alcohol

[cik2e]

https://en.m.wikipedia.org/wiki/Truth_serum

TL;DR No, there aren’t.

[actuator]

All the Reliability section of that page says is, there isn't a randomised study you can trust.