ADHD News & Research

ADHD Meds Reduce the Risk for Car Crashes

People with ADHD experience car accidents at a significantly higher rate than their peers, but a new study finds that taking ADHD medication may significantly lower that risk.

May 16, 2017

People with ADHD were less likely to be involved in car crashes during periods they were being treated with ADHD medication, a large nationwide study finds.

Motor vehicle crashes are a common (and preventable) cause of injury and death in the U.S — and people with ADHD may be at a higher risk. Impulsivity and distractibility have been shown to be a dangerous combination on the road, with some studies finding that people with ADHD have one-and-a-half times the risk of being involved in a car crash than people without the condition.

The current study, conducted by the Karolinska Institutet in Stockholm, found a similar risk: Men with ADHD were at 1.49 times greater risk than their counterparts without ADHD, while females with ADHD were at 1.44 times the risk. Researchers used insurance claims from January 2005 to December 2014 to identify more than 2 million adults who had been diagnosed with ADHD in the United States and track their medication use, both stimulants and nonstimulants. The average age of the subjects was 32.5 years; just over half were female.

The results reflected positively on ADHD medications. Males with ADHD were 38 percent less likely to experience a car crash during the periods they were taking medication, and women fared even better — females with ADHD were 42 percent less likely to be involved in a car accident when they were taking meds. The effects were so strong, in fact, that researchers estimated that 22.1 percent of possible crashes during the observed period were prevented by the use of ADHD medications.

“If replicated, our results should be considered along with other potential benefits and harms associated with ADHD medication use,” said Zheng Chang, Ph.D., the lead author of the study.

Vishal Madaan, M.D., and Daniel J. Cox, M.D., both of the University of Virginia Health System in Charlottesville, agreed with Chang’s conclusion in an accompanying editorial, but they cautioned that medications should not be considered an infallible solution to the problem of ADHD-related car crashes.

“Clinicians should not presume that all ADHD medications at any dosage will be effective for every patient,” they write. “Health-care professionals should ensure that both the medication and dosage are optimal for a particular patient-driver, that the medication coverage is adequate for the particular patient’s driving routine, and that the medication prescribed is not responsible for worse driving as its effects wear off (rebound effect).”