The National Transportation Safety Board has published an updated study on drug presence among fatally injured pilots, showing increases in both overall drug detection and the presence of drugs the agency classified as potentially impairing.
The report, 2018–2022 Update to Drug Use Trends in Aviation, examined toxicology results from 930 pilots killed in U.S. civil aviation accidents from 2018 to 2022. According to the NTSB, 52.8% of those pilots tested positive for at least one drug of any type, including medications such as cardiovascular drugs, cholesterol-lowering drugs and nonsedating over-the-counter medications. The study separately found that 28.6% tested positive for drugs classified as potentially impairing, a category that includes some prescription and over-the-counter medications, controlled substances and illicit drugs.
The most commonly detected potentially impairing drug remained diphenhydramine, a sedating antihistamine used in many allergy and nighttime cold medications. The NTSB also reported that illicit drug detection rose to 7.4%, with the increase primarily tied to delta-9-THC, the primary psychoactive chemical in marijuana. Drug presence was lower among Part 135 pilots than among general aviation pilots, lower among pilots with an active medical certificate than those without one, and lower among pilots holding airline transport or commercial certificates than among private, sport or student pilots, or those with no certificate.
The NTSB noted that a positive toxicology result does not, by itself, establish impairment. The agency also cautioned that pilots should not infer that a drug may be used safely or legally based on how it was classified in the report, noting that some drugs outside its potentially impairing category may still have impairing effects, may be used to treat conditions that affect flying or may be subject to FAA restrictions.