(Associated Press) Increased use of medical marijuana may lead to more young children getting sick from accidentally eating food made with the drug, a Colorado study suggests. Medical marijuana items include yummy-looking gummy candies, cookies and other treats that may entice young children. Fourteen children were treated at Colorado Children's Hospital in the two years after a 2009 federal policy change led to a surge in medical marijuana use, the study found. That's when federal authorities said they would not prosecute legal users. Study cases were mostly mild, but parents should know about potential risks and keep the products out of reach, said lead author Dr. George Sam Wang, an emergency room physician at the hospital. Unusual drowsiness and unsteady walking were among the symptoms. One child, a 5-year-old boy, had trouble breathing. Eight children were hospitalized, two in the intensive care unit, though all recovered within a few days, Wang said. By contrast, in four years preceding the policy change, the Denver-area hospital had no such cases. Some children came in laughing, glassy-eyed or "acting a little goofy and 'off,'" Wang said. Many had eaten medical marijuana food items, although nonmedical marijuana was involved in at least three cases. The children were younger than 12 and included an 8-month-old boy. Eighteen states and Washington, D.C., allow medical marijuana, though it remains illegal under federal law. Colorado's law dates to 2000 but the study notes that use there soared after the 2009 policy change on prosecution. Last year, Colorado and Washington state legalized adult possession of small amounts of nonmedical marijuana. Some states, including Colorado, allow medical marijuana use by sick kids, with parents' supervision. Cannabis Gummy Bears