Hundreds of families throughout the world have been drawn to Colorado to seek medical marijuana treatment for their children's ailments. These parents and their kids, dubbed “international medical marijuana refugees,” travel thousands of miles in an attempt to procure what they say are lifesaving elements, the Guardian reported Monday.

“We’re not going to choose the option of being criminals with this in Ireland,” Yvonne Cahalane, a young mother who relocated from Ireland to Colorado on a one-year visa with her two sons to seek treatment for her youngest boy, told the Guardian. Her 2-year-old son has a rare form of epilepsy that was causing him to have near-constant seizures, and since seeking treatment in that state, he hasn't had a seizure in months. “We don’t want to do things illegally, and we don’t want to do it without a doctor,” she said.

No statistical evidence is available on the number of people who have come to the U.S. to seek this treatment, but Cahalane and her family are estimated to be several of hundreds of people who have sought cannabis treatment not available in their home countries for chronic ailments. As of the end of April, 24 states and Washington, D.C., had made some form of marijuana legal. Colorado in particular has attracted treatment-seekers, given its longer history of medical marijuana as well as the presence of advocacy groups and doctors devoted to its study and use.

Medical marijuana has been used to treat a variety of illnesses and chronic conditions, including depression, epilepsy and pain management for diseases like cancer. There are only a limited number of studies on the uses of cannabis to treat illness, as the drug is still illegal on the federal level and scientists often encounter obstacles to receiving federal funding for their studies.

A group of researchers in Colorado were recently given the green light to begin a study concerning the use of medical marijuana to treat post-traumatic stress disorder in veterans — the first study of its kind in the state.

Without Colorado’s initiative in setting aside money for this, this work couldn’t get done,” Marcel Bonn-Miller, principal investigator for the study, told CNN. “The biggest stumbling block or barrier to this research is funding, more so than federal regulations or red tape.”