IV.

Effectiveness and Side Effects

All antidepressants decrease symptoms of depression in about 70 percent of depressed people who take them. With most antidepressants, three weeks or more of treatment is necessary before beneficial effects occur. Although no antidepressant is more effective overall in treating depression than the others, some people respond better to one drug than to another, and they may have to try more than one before finding the most beneficial drug.

Doctors also decide which antidepressant to prescribe according to the type of side effects an individual can tolerate. For instance, a person who takes TCAs and MAO inhibitors may notice dizziness and fainting when standing up, mouth dryness, difficulty urinating, constipation, and drowsiness. If people who take MAO inhibitors eat certain foods, such as aged cheese or some aged meats, they can experience severe headaches and raised blood pressure. SSRIs can cause side effects such as restlessness, difficulty sleeping, and interference with sexual function.

Awareness of the side effects associated with a drug is important. People who suffer from insomnia will want to avoid an antidepressant associated with difficulty sleeping. It is also important for patients on antidepressants to report any other medical conditions they have or drugs they are taking to the prescribing physician. Certain antidepressants, for example, carry a risk of liver problems. Some antidepressants cannot be combined with certain other drugs. Some should not be taken by pregnant women.

In 2007 a Canadian study reported that people over 50 who take SSRIs have twice the risk of sustaining a bone fracture as people not taking these drugs. SSRIs appear to increase the risk of falls. They also have some effect on bone formation, so it is a wise idea for people on these drugs to exercise and increase calcium and vitamin D intake to help combat the risk of fracture.