Taking too much dextromethorphan (DXM) can cause a range of negative and potentially dangerous side effects. DXM is an over-the-counter cough suppressant, but when taken in excessive amounts, it can have hallucinogenic effects similar to those of ketamine or PCP. Here are some potential effects of taking too much DXM: Nausea and vomitingDizziness and disorientationConfusion … Continue reading What If I Take Too Much Dextromethorphan