Tasers, those little gun-shaped canisters used by law enforcement to deploy coils of high-voltage, electric shock to criminal suspects, might do more to people than merely subdue them.

A study published Tuesday in British Medical Journal, suggests that an increase in Taser use across law enforcement agencies worldwide has sparked a confluence of reported skin burns, injuries to muscles, joints, and tendons, and seizures in both healthy people and those who have epilepsy.

Tasings can cause ventricular fibrillation — shocking the heart into not pumping blood — and momentary paralysis, which causes victims to fall to the ground, immobilized. Probably to the surprise of no one, uncontrolled falls have caused head injuries, like concussions and contusions.

The study warrants pause, being that Tasers are often looked to as a less-than-lethal cousin to firearms and instruments that cause blunt force trauma: The BMJ study found that, “conducted electrical weapons are used by over 16,000 police forces in 107 countries,” and that “worldwide, tasers have shocked people roughly 1.35 million times, 650,000 of them during arrests and stops and 700,000 during police training.”

Most law enforcement agencies are supplied by Taser International, a manufacturer based in Arizona, which produces the most widely-used X26 model. Increased scrutiny of the weapon doesn’t seem to have done the company’s stock any favors: It’s trading at about half of its high mark of this past summer.