Avoid drinking alcohol. It can increase some of the side effects of dextromethorphan. This medication can cause side effects that may impair your thinking or reactions. Be careful if you drive or do anything that requires you to be awake and alert.
Avoid taking diet pills, caffeine pills, or other stimulants (such as ADHD medications) without your doctor's advice. Taking a stimulant together with cough medicine can increase your risk of unpleasant side effects.
Do not use any other over-the-counter cough, cold, or allergy medication without first asking your doctor or pharmacist. Dextromethorphan is contained in many combination medicines available over the counter. If you take certain products together you may accidentally take too much of this medicine. Read the label of any other medicine you are using to see if it contains dextromethorphan.
