The use of metoclopramide may cause some people to feel dizzy, lightheaded, tired, or less alert than they are normally. For the first 24 to 48 hours, patients should be cautious when driving, using machinery, or performing hazardous activities. This medicine will add to the effects of alcohol and other central nervous system depressants-such as medicines for allergies and colds, tranquilizers, and prescription pain relievers. Patients need to check with the research team before taking any of those types of medicines, as well as herbal supplements, while using metoclopramide.