CAPE CORAL, Fla. -- Authorities in southwest Florida said two 19-year-old men are dead and another man is hospitalized after they apparently overdosed on a drug found in an over-the-counter cold medicine.

Cape Coral police said Alex Kulwicki and two friends were found unconscious early Sunday in a home.

The two men died at the scene, while Kulwicki was taken to an area hospital in critical condition.

Police believe the men took too much Coricidin HBP Cough & Cold, which contains dextromethorphan.

While it is legitimately used to treat colds or allergy symptoms, when taken in high doses dextromethorphan can cause hallucinations and a sense of dissociation. Effects can last as long as six hours.

In high doses, the drug can cause increased body temperatures, irregular heart beat, high blood pressure, loss of consciousness, seizure, brain damage and death. The men were believed to have obtained the drug over the Internet.