Answer:
Several drugs can cause the pupillary dilatation, the most common are the following:
LSD, psilocybin mushrooms, mescaline, 2C-B, GHB, MDMA, cocaine
Explanation:
Some stimulants as amphetamines, cocaine, MDMA and Mephedrone can cause Mydriasis, which is the the over dilation of the pupil by non-physiological causes. Serotonergics as LSD-25 and psilocybin found in mushrooms also can cause the Mydriasis.