“In certain cases, they can even cause death, as has been shown by reliable studies and recent real-life events,” the committee of 10 experts said.
Three men, all in their early 20s, were reported to have died in the United States this week, days after a Polish man died at Vancouver airport after being Tasered by Canadian police.
The man, Robert Dziekanski, 40, fell to the ground and died after the police officers piled on top of him.
There have been three deaths in Canada after the use of Tasers over the past five weeks.
The company that makes the weapons has said that similar deaths have been shown by “medical science and forensic analysis” to be “attributable to other factors and not the low-energy electrical discharge of the Taser”.
The UN committee made its comments in recommendations to Portugal, which has bought the newest Taser X26 stun gun for use by police.
Portugal “should consider giving up the use of the Taser X26,” as its use can have a grave physical and mental impact on those targeted, which violates the UN’s Convention against Torture, the experts said.