According to a study in the February issue of the Journal of Clinical Sleep Medicine, 10 percent of adolescents who displayed excessive daytime sleepiness indicative of narcolepsy screened positive for marijuana. The authors concluded that drug screening is important when evaluating teens for excessive daytime sleepiness.

Read full study “Urine Toxicology Screen in Multiple Sleep Latency Test: The Correlation of Positive Tetrahydrocannabinol, Drug Negative Patients, and Narcolepsy” in Journal of Clinical Sleep Medicine