Five California high school students have been hospitalized in the last two weeks because of overdosing on cough medication, a school administrator told NBC Bay Area on Wednesday. Three students from Tamalpais High School took too much Coricidin and were found in class, and two students at Drake High School overdosed on cough medication at a school dance about 10 days ago.

Health officials say it’s a dangerous and potentially deadly trend among teens: taking cough medicine to get high. Wes Cedros, the Tamalpais Union High School District Senior Director of Student Services, said all of the students involved have been treated and referred to counseling, but that the incidents are “an alarming wake up” call.

Coricidin is also referred to by its street names, “Triple C” and “Skittles.” A commonly used — and abuse — over-the-counter cod medication, Coricidin contains an active ingredient of dextromethorphan (DXM). The drug is found in over 120 cold medications, sometimes in combination with other drugs, including acetaminophen and pseudoephedrine.

A typical dose is around 15-30 mg, but when taken in large quantities, DXM can cause a dissociative feeling, euphoria, and hallucinations. The side effects of an overdose can be nasty, though, including vomiting, dizziness, impaired motor control, and dilated pupils. The most severe overdoses can result in a seizure, coma, and even death. dxM-related deaths also include accidents, since the drug impairs the senses and opens the door to risky behaviors and judgment calls.

Since cough medicines are readily available in drugstores, part of the reason Coricidin abuse has been on the rise nationally. Teens are taking it from their medicine cabinets at home, or receiving it from friends. There is even extensive “how-to” information on the Internet, guiding people on how to abuse DXM. Health officials recommend parents begin a dialogue with their children about the dangers of cough syrup overdose.