A University of South Florida neurology team studied two healthy, young siblings who experienced acute ischemic strokes soon after smoking the street drug spice or K2.
Ischemic strokes occur when an artery to the brain is blocked, researchers said.
Seizures, abnormal heart rhythms, heart attacks, psychosis, hallucinations and other serious adverse effects have been associated with smoking synthetic pot, researchers said.
"Since the two patients were siblings, we wondered whether they might have any undiagnosed genetic conditions that predisposed them to strokes at a young age. We rigorously looked for those and didn't come up with anything," said senior author W Scott Burgin, professor of neurology at the USF Health Morsani College.
Synthetic marijuana refers to a mixture of herbs, often resembling lawn clippings, that have been sprayed or soaked with a solution of designer chemicals intended to produce a high similar to cannabis when consumed.
Spice can be much more potent than conventional marijuana because of the more complete way the psychoactive ingredient in the synthetic product binds to the brain's cannabinoid receptors, Burgin said.
People who smoke spice expose their brains to unidentified chemicals untested on humans.
Not identified in standard toxicology screens, spice has become the second only to natural marijuana as the most widely used illicit drug among high school seniors, according to a 2011 survey sponsored by the National Institute on Drug Abuse.
More physicians need to be more aware of the potentially toxic effects of recreational synthetic drugs, especially when seeing conditions like heart attack or stroke not as common in young patients, Burgin said.
