"LSD ('acid', 'trips') is a hallucinogenic drug which can last from 8-12
hours. Once the experience starts there is no way you can stop the
process and whilst some people may experience a good 'trip', others may
become tense, panicky or paranoid.
"If you are upset, worried about something or in a strange environment
you are more likely to experience a bad trip.
"If this happens to someone you know, take them to quiet surroundings
away from bright lights and loud music. Reassure the person that these
feelings will gradually wear off and try to keep them calm. Try and stay
with them until they are feeling OK.
"The only truly safe option is not to take LSD at all."