DXM is a common abbreviation for dextromethorphan, a cough suppressant in over-the-counter medications. Some common synonyms for DXM include robitussin, tussin, cough syrup, and cold medicine. DXM can also be referred to as DM or Dextrometh. Misuse of DXM can result in dangerous side effects, including hallucinations, increased heart rate, and loss of consciousness. It is important to always follow the recommended dosages and not exceed the maximum daily amount. Additionally, it is important to not mix DXM with other substances, such as alcohol or prescription medications. If you experience any adverse reactions or symptoms after taking DXM, seek medical attention immediately.