With all types of THC and marijuana products now easily available to adults, edibles are a source of particular concern for parents: How can you keep your child safe when a THC-infused treat could easily be mistaken for a regular brownie or piece of brightly-colored candy? Here’s why it’s important to keep your kids away from THC—particularly edibles, which often contain a higher concentration of the chemical than marijuana alone—and how to do so.

Ingestion of THC by a child can have “a spectrum of symptoms, from a little bit of ‘goofy behavior,” drowsiness and imbalance, to coma and difficulties breathing,” according to Dr. G. Sam Wang, doctor of pediatric emergency medicine and toxicology at Children’s Hospital Colorado.

Many ongoing studies have shown that consumption of THC by minors can have long-term negative effects on developing brains. Youth who use marijuana regularly are more likely to have a hard time learning, problems remembering and lower math and reading scores.

If you suspect your child has ingested THC, call poison control right away at 1-800-222-1222. If his or her reaction seems severe, take your child to the nearest emergency room immediately.

Retail and medical marijuana businesses are now required to sell all marijuana products in packaging that is opaque, resealable, child-resistant (up to age 5) and includes labels and warnings about what is inside.

New regulations of marijuana-infused edibles, relating to packaging and potency, went into affect on Feb. 1, 2015. The regulations require that edibles be packaged in single servings or be marked in a way that makes it easy to identify a single serving size of active THC. A single serving may contain no more than 10 milligrams of THC and each package is limited to 100 milligrams of THC.

Further labeling regulations were outlined in the fall of 2015, requiring that all edible retail marijuana products be stamped, colored or otherwise marked with a universal symbol indicating that it contains marijuana and is not for consumption by children. The symbol is shown as a red or black outlined diamond with the letters THC and an exclamation point inside.

It may take up to four hours before consumers notice any effects of edible marijuana, longer if eaten after a meal.

If you are unsure of a food or candy that is outside of its original packaging, you can purchase a $15 THC test kit either online or at select dispensaries.

If you have marijuana edibles in the house, make sure you store them in their original packaging and don’t keep them near other foods. If you have a liquor cabinet, safe or anything lockable that your kids don’t have access to, consider keeping your edibles there.

Worried that your children will be exposed at a friend’s or a neighbor’s house? Don’t be afraid to broach the subject with other parents, and remind your children not to eat anything while they are a guest, unless they”ve first asked their host’s permission.

As with alcohol and tobacco, you should have a frank discussion with your kids about the negative effects of THC starting at an early age. For conversation tips, go to GoodToKnowColorado.com/talk.

Read part one of this special series: Parenting in a Marijuana-Legal State