Over-the-counter cold and cough medicines containing the drug Dextromethorphan (DXM) have also been abused. DXM is sold in syrup, gel and tablet form. When sold on the Internet as powder, it is particularly risky because of the uncertainty of its composition and dose. It is found in more than 100 products; Coricidin and Robitussin are abused the most.
EFFECTS

    Visual hallucinations
    Hyperexcitability
    Insomnia
    Lethargy
    Physical dependence (with prolonged use)
    Dizziness
    Slurred speech
    Delusions
    Sweating
    High blood pressure
    Liver and brain damage

Mixed with other drugs, cough syrup can also cause central nervous system and heart problems. Combined with alcohol, it is particularly dangerous and can result in death.