Soundness of mind

What are the side effects of NyQuil?

The most common side effects of NyQuil include drowsiness, dizziness, nausea, vomiting, and headache. It can also cause dry mouth and constipation. More serious side effects may include difficulty breathing, irregular heartbeat, loss of consciousness, and seizures. If any of these side effects occur, it is important to stop using NyQuil and contact a doctor right away.