Is 4/20 an Event-Specific Marijuana Holiday? A Daily Diary Investigation of Marijuana Use and Consequences Among College Students.

OBJECTIVE Given the popular association between April 20 ("4/20") and marijuana, the present study examined marijuana use and consequences on 4/20 compared with other days in order to test whether 4/20 is a high-risk, event-specific marijuana use holiday among college student marijuana users. METHOD Fifty-nine college student marijuana users from three different, large U.S. universities located in Virginia, New Mexico, and Colorado completed daily brief surveys (<10 minutes) over a 12-day (April 15-April 26) period assessing prior-day marijuana use (i.e., percentage of users who consumed marijuana, number of unique marijuana use sessions, subjective high/intoxication while under the influence of marijuana, and number of grams of marijuana consumed) and marijuana-related consequences. RESULTS Using oneway repeated-measures analyses of variance, we found that (a) 50% of students reported using marijuana on 4/20, which was significantly more than weekdays (28%) and weekend days (37%); (b) students reported a significantly higher number of unique marijuana use sessions on 4/20 (M = 1.47) compared with weekdays (M = 0.91); and (c) students reported a significantly higher number of grams consumed on 4/20 (M = 0.79) compared with weekdays (M = 0.35) and weekend days (M = 0.47). CONCLUSIONS Our study provides preliminary support that 4/20 is a day associated with increased marijuana use but provides little evidence for an association with more problematic use.