Taking an MAOI antidepressant at the same time as any other antidepressants or certain over-the-counter medicines for colds and flu can cause a dangerous reaction. Your doctor will tell you what foods and alcoholic beverages you should avoid while you are taking an MAOI. You should not take an MAOI unless you clearly understand what medications and foods to avoid. If you are taking a MAOI and your doctor wants you to start taking one of the other antidepressants, he or she will have you stop taking the MAOI for a while before you start the new medicine. This gives the MAOI time to clear out of your body.
Another risk of antidepressants is serotonin syndrome, a drug reaction resulting from the over-stimulation of serotonin receptors. This can occur when an antidepressant is taken either with another antidepressant, with certain recreational and other drugs (see below), or more rarely, even when one antidepressant is taken alone. Symptoms include hyperactivity, mental confusion, agitation, shivering, sweating, fever, lack of coordination, seizure, and diarrhoea.
To minimise the risk of serotonin syndrome, there must be a 'washout' period of at least two weeks when switching from one antidepressant drug to another.