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Am Fam Physician. 2000;61(5):1525-1526

What is depression?

Depression is a medical illness like diabetes or high blood pressure. People don't choose to be depressed. They aren't weak or “crazy.” Depression is an illness. It affects about 17 percent of people at some time in their lives. It's twice as common in women as in men.

Symptoms of depression include the following:

  • Feeling sad most of the day, nearly every day, for two weeks or longer

  • Loss of interest in things you used to enjoy

  • Lack of energy

  • Sleep and appetite disturbances

  • Weight changes

  • Feelings of hopelessness, helplessness and worthlessness

  • Not being able to make decisions

  • Thoughts of death and suicide

What causes depression?

The exact cause of depression is not known. Doctors think it may be caused by a chemical imbalance in the brain. The imbalance could be caused by your genes or by events in your life.

How will my doctor treat my depression?

Depression can be treated with medicines and counseling. The combination of medicine with counseling helps most people. Counseling can help you change a negative view of yourself, of your past and of your future. Regular exercise and avoiding too much caffeine, alcohol and illegal drugs can also help.

More than 20 medicines treat depression. These medicines are called antidepressants. They help balance the chemicals in your brain that affect your mood.

How will my doctor pick an antidepressant for me?

Your doctor will think about these 10 points when choosing an antidepressant medicine for you:

  1. If you had depression before and a certain antidepressant worked well, this might be the best choice of medicine for you again.

  2. If any of your brothers and sisters, your parents, uncles or aunts had depression and a certain antidepressant worked well for them, that medicine might be good for you, too.

  3. The choice of an antidepressant also depends on your health. If a certain antidepressant would have a bad effect on a health problem, that medicine wouldn't be good for you.

  4. Antidepressants may cause side effects. No antidepressant is totally free from side effects. The best medicine for you is the one that gives you the fewest side effects.

  5. The choice of an antidepressant also depends on how often you have to take it. The less often you have to take the medicine, the easier it is for you to take all the doses you need to treat your depression.

  6. Some antidepressants cost more than others. Your doctor will choose an antidepressant that works well for you and that you can afford.

  7. Your doctor will want to choose a medicine he or she knows a lot about.

  8. An antidepressant should be able to help you with symptoms like sleeplessness, anxiety and lack of energy. Your doctor will want to choose a medicine that will help you right away with these symptoms.

  9. If you're taking other medicines, it's important to consider how an antidepressant will work with the other medicines.

  10. Some antidepressants don't work well with some foods. Your doctor will either not give you that kind of antidepressant or you will have to stop eating those foods.

What are the different kinds of antidepressants?

  • Tricyclic antidepressants (tricyclics)

  • Selective serotonin reuptake inhibitors (SSRIs)

  • Monoamine oxidase inhibitors (MAOIs)

  • Others


The tricyclic antidepressants have been used to treat depression for a long time. They include amitriptyline (brand name: Elavil), desipramine (brand name: Norpramin), imipramine (brand name: Tofranil) and nortriptyline (brand name: Pamelor). Common side effects caused by these medicines include dry mouth, blurred vision, constipation, difficulty urinating, worsening of glaucoma, impaired thinking and tiredness. These antidepressants can also affect blood pressure and heart rate.


SSRIs are a newer group of antidepressants and include drugs such as fluoxetine (brand name: Prozac), paroxetine (brand name: Paxil) and sertraline (brand name: Zoloft). These medicines tend to have fewer side effects than the tricyclics. Some of the side effects that can be caused by SSRIs include decreased appetite, nausea, nervousness, insomnia, headache and sexual problems. People taking fluoxetine might also have a feeling of being unable to sit still. People taking paroxetine might have a dry mouth and feel tired. People taking sertraline might have diarrhea.


Taking an MAOI antidepressant at the same time as any other antidepressant might be fatal. MAOIs include phenelzine (brand name: Nardil) and tranylcypromine (brand name: Parnate). If you are taking an MAOI and your doctor wants you to start taking one of the other antidepressants, you will have to stop taking the MAOI for a while before you can start the new medicine. This gives the MAOI time to get out of your body.

Other antidepressants

The most common side effects in people taking venlafaxine (brand name: Effexor) include nausea and loss of appetite, anxiety and nervousness, headache, insomnia and tiredness. Dry mouth, constipation, weight loss, sexual problems, increased blood pressure, increased heart rate and increased cholesterol levels can also occur.

Nefazodone (brand name: Serzone) can cause headaches, blurred vision, dizziness, nausea, constipation, dry mouth and tiredness.

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