Old spanish show were they experimented drugs on a man

Hello, i have been trying to find this old tv show about a man that did drugs on camera and they documented his reactions.

I know of this show as i know of the man that consumed the drugs (lets call him John, as i dont know if he wants his name out) unfortunatly he had some really bad health issues and lives very far away from me as I live in another country, so we cant contact him well and he isnt in the best way right now. He is a friend of my father and everything i will describe is what John told him:

The show was filmed wen he was in his 20's so it was probably filmed in Mexico from 1960's to 1970's i believe.

He sayed there used to be a doctor next to him, but i dont know if he could be seen in the shots.

The director is a spanish man my father believes, John sayed the name of the director wen they were talking about it, but it was long ago so my father doesnt remember.

The show was about John doing different types of drugs on camera, then they analysed his reactions, i do not know more than that.

It was aired in Spanish tv, i presume at the time of the recordings, i dont know if it aired on another countries, maybe in Mexico.

I know the information is very small but its what we have. Anyways, thank you.