Objectives Methamphetamine is considered to be one of the most popularly abused drugs by drivers; however, its exact effect on driving
and driving behaviour has yet to be thoroughly investigated. This being despite methamphetamine’s increased prevalence in injured and deceased
Methods Twenty healthy recreational illicit stimulant users (10 male and 10 female), aged between 21 and 32 years (mean = 25.4 years,
SD = 3.3 years) attended two testing sessions involving oral consumption of 0.42 mg/kg d-methamphetamine or a matching placebo. The
drug administration was counter-balanced, double-blind, and medically supervised. At each session driving, performance was assessed
2.5 h post drug administration.
Results d-methamphetamine (0.42 mg/kg) did not significantly impair overall simulated driving performance 2.5 h post drug administration.
At the individual driving variable level, participants in the d-methamphetamine condition were observed to be driving slower when
an emergency situation occurred (T = 44, p<0.05), but interestingly, participants in both conditions recorded average speeds in excess of
the speed limit (100 km/h) when the emergency situations occurred. The d-methamphetamine condition did also produce four times more
infringements where participants did not stop at red traffic light in comparison to the placebo, but this effect was only evident at a trend level
(T=7, p = 0.11).
Conclusions The findings presented herein suggest that d-methamphetamine administered at the levels supplied did not impair driving performance
in a manner consistent with epidemiological evidence. Further research is certainly required to elucidate the effects of various doses
of methamphetamine, alone and in combination with other legal and illicit substances.