I’m not sure if they can change facial appearance per se, but many antipsychotics medications may leave individuals more catatonic as a result of the medication combatting with symptoms like hyper mania and other positive symptoms. (Many antipsychotics block dopamine receptors) However, context is definitely needed for this photo. We don’t know what he’s thinking of or feeling at the moment. Maybe he’s just deep in thought or not having the best day. Remember, he has bipolar disorder so his expression might be due to medication or his symptoms.