Lsd and mescaline are forms of
a. depressants.
b. hallucinogens.
c. narcotics.

These two drugs are forms of hallucinogens. What this simply means is that the side effect that the drug brings is for individuals to experience hallucinations. Due to its psychoactive content, experiences such as, perception anomalies, and changes in thoughts, emotions, and consciousness are severely affected. Though it does not directly impair vision and no pain is associated with the intake of this drug.  Common hallucinogens are psychedelics, dissociatives, and deliriants. This was a common drug during the time of the hippies. 

It hurts for them at first then they get used to it