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Any competitive 5-HT2A antagonist will block psychedelic effects from classical psychedelic drugs, and D2 antagonists will block the potential for stimulant-esque psychosis that drugs like LSD can trigger through dopamine agonism.

There are probably hundreds of drugs that fall into these classes, and many of them have significant clinical data to derive their safety profiles from.

If someone comes into a hospital with a bad reaction to psychedelic drugs, it's not uncommon for them to be given something like risperidone, both a 5-HT2A and D2 antagonist, and an anxiolytic to calm them down.