The disorder depression is a feeling of sadness intense enough to interfere with functioning. It may follow a recent loss or other sad event but is out of proportion to that event and lasts beyond an appropriate length of time.

• Heredity, side effects of drugs, emotionally distressing events, imbalances in the body, and other factors can contribute to depression.
• Depression can make people sad and sluggish or anxious and fearful.
• Doctors base the diagnosis on symptoms.
• Antidepressants, psychotherapy, and sometimes electroconvulsive therapy can help.

After anxiety, depression is the most common mental health disorder. About 30% of people who visit a primary care practitioner have symptoms of depression. However, only some of these people have major depression. People who become depressed typically do so in their mid teens, 20s, or 30s, although depression can begin at almost any age, including during childhood (see Mental Health Disorders in Children: Depression in Children). People born in the latter part of the 20th century seem to have higher rates of depression and suicide than those of previous generations, in part because rates of substance abuse have increased.

Spotlight on Aging
Depression affects about 1 of every 6 older people. Some older people have had depression earlier in their lives. Others develop it for the first time during old age. Some causes of depression may be more common among older people. For example, older people may be more likely to experience emotionally distressing events that involve a loss, such as the death of a loved one, the ending of a significant relationship, or a loss of familiar surroundings, as when moving away from a familiar neighborhood. Other sources of stress, such as reduced income, a worsening chronic illness, a gradual loss of independence, or social isolation, may also contribute. Disorders that can lead to depression are common among older people. Such disorders include cancer, heart attack, heart failure, thyroid disorders, stroke, dementia, and Parkinson's disease. In older people, depression can cause symptoms that resemble those of dementia: slower thinking, decreased concentration, confusion, and difficulty remembering. Depression can so resemble dementia that it is sometimes called dementia of depression or pseudodementia. However, doctors can distinguish depression from dementia because the symptoms resolve when depression is treated. Symptoms of dementia do not. Depression is often difficult to diagnose among older people for several reasons: The symptoms may be less noticeable because older people may not work or may have less social interaction. Some people believe that depression is a weakness and are reluctant to tell anyone that they are experiencing sadness or other symptoms. The absence of emotion may be interpreted as indifference rather than depression. Family members and friends may regard a depressed person's symptoms simply as evidence that the person is getting older. The symptoms may be attributed to another disorder, such as dementia. Because depression may be difficult to identify, many doctors routinely ask older people questions about their mood. Family members should be alert for subtle changes in personality, especially lack of enthusiasm and spontaneity, loss of sense of humor, and new forgetfulness. Selective serotonin reuptake inhibitors (SSRIs) are the antidepressants used most often for older people who are depressed. They are less likely to have side effects. CitalopramSome Trade Names CELEXA and escitalopramSome Trade Names LEXAPRO are particularly useful.

An episode of depression, if untreated, typically lasts about 6 months but sometimes lasts for 2 years or more. Episodes tend to recur several times over a lifetime.

Causes

The exact cause of depression is unclear, but a number of factors may make depression more likely. They include a family tendency (heredity), side effects of certain drugs, and emotionally distressing events, particularly those involving a loss. Depression does not reflect a weakness of character and may not reflect a personality disorder, childhood trauma, or poor parenting. Depression may arise or worsen without any apparent or significant life stresses.

Genetic abnormalities may contribute. They can affect the function of substances that help nerve cells communicate (neurotransmitters). Serotonin, dopamine and norepinephrineSome Trade Names
LEVOPHED
are neurotransmitters that may be involved in depression.

Social class, race, and culture do not appear to affect the chance that people will experience depression during their lifetime. However, a person's sex does: Women are twice as likely as men to experience depression, although the reasons are not entirely clear. Of physical factors, hormones are the ones most involved. Changes in hormone levels, which can cause mood changes shortly before menstruation and after childbirth, might play some role in women. In women, levels of enzymes that affect mood may be higher. Abnormal thyroid function, which is fairly common among women, may also be a factor.

People with transient depression become temporarily depressed in reaction to certain situations:

• Holidays (holiday blues)
• Meaningful anniversaries, such as the anniversary of a loved one's death
• Before menstrual periods (premenstrual syndrome, or if the depression is more serious, premenstrual dysphoric disorder)
• During the first 2 weeks after giving birth (baby blues or, if the depression is more serious, postpartum depression)

Such reactions are normal and do not lead to severe, lasting depression except in people predisposed to depression. Depression may occur with or be caused by a number of physical disorders. Physical disorders may cause depression directly (as when a thyroid disorder affects hormone levels) or indirectly (as when rheumatoid arthritis causes pain and disability). Often, a physical disorder both directly and indirectly causes depression. For example, AIDS may cause depression directly if the human immunodeficiency virus (HIV), which causes AIDS, damages the brain. AIDS may cause depression indirectly by having an overall negative effect on the person's life.

The use of some prescription drugs can cause depression. For unknown reasons, corticosteroids often cause depression when the body produces them in large amounts as part of a disorder (as in Cushing's syndrome), but they tend to cause hypomania or, rarely, mania when they are given as a drug. Sometimes stopping a drug can cause depression.

A number of mental health disorders can predispose a person to depression. They include certain anxiety disorders, alcoholism, other substance abuse disorders, and schizophrenia. People who have had depression are more likely to have it again.

PrintOpen table in new window
Some Causes of Depression Condition Examples Brain and nervous system disorders Brain tumors Dementia (in early stages) Head injury Multiple sclerosis Parkinson's disease Sleep apnea Stroke Seizures that affect the temporal lobe (complex partial seizures) Cancers Abdominal cancers (ovary or colon) Cancer spreading throughout the body (metastatic) Cancer of the pancreas Connective tissue disorders Systemic lupus erythematosus (lupus) Hormonal disorders Addison's disease Cushing's syndrome Diabetes High levels of parathyroid hormone Low and high levels of thyroid hormone Low levels of pituitary hormones (hypopituitarism) Infections AIDS Influenza Mononucleosis Syphilis (late stage) Tuberculosis Viral hepatitis Viral pneumonia Nutritional disorders Pellagra (vitamin B6 deficiency) Pernicious anemia (vitamin B12 deficiency) Drugs Alcohol AmphetamineSome Trade Names ADDERALL withdrawal Amphotericin BSome Trade Names FUNGIZONE Antipsychotic drugs Beta-blockers (some) CimetidineSome Trade Names TAGAMET Contraceptives (oral) Corticosteroids CycloserineSome Trade Names SEROMYCIN Hormone (estrogen) therapy Interferon Mercury Methyldopa MetoclopramideSome Trade Names REGLAN Reserpine Thallium Vinblastine Vincristine

Symptoms

Symptoms typically develop gradually over days or weeks and can vary greatly. For example, a person who is becoming depressed may appear sluggish and sad or irritable and anxious.

Many people with depression cannot experience emotions—including grief, joy, and pleasure—in a normal way; in the extreme, the world appears to have become colorless and lifeless. Depressed people may be preoccupied with intense feelings of guilt and self-denigration and may not be able to concentrate. They may experience feelings of despair, loneliness, and low self-esteem. They are often indecisive and withdrawn, feel progressively helpless and hopeless, and think about death and suicide.

Symptoms can vary depending on the type of depression.

• Catatonic depression: People are very withdrawn. Thinking, speech, and general activity may slow down so much that all voluntary activities stop. They may not take care of their children or pets or even feed themselves. Some people mimic others' speech (echolalia) or movements (echopraxia).
• Melancholic depression: People do not receive pleasure from activities they usually enjoy. They appear sluggish, sad, and withdrawn. They speak little, stop eating, and lose weight. Their face may show no emotions. They may feel excessively or inappropriately guilty.
• Psychotic depression: People have false beliefs (delusions), often of having committed unpardonable sins or crimes, of having incurable or shameful disorders, or of being watched or persecuted. People may have hallucinations, usually of voices accusing them of various misdeeds or condemning them to death. A few imagine that they see coffins or deceased relatives.
• Atypical depression: People with this type appear anxious and fearful (especially in the evening). They have an increased appetite, resulting in weight gain, and although initially unable to sleep, they sleep for increasingly longer periods. They tend to cheer up in response to positive events but are excessively sensitive to perceived criticism or rejection. Some people become agitated. They are very restless—wringing their hands and talking continuously.

Most depressed people have difficulty falling asleep and awaken repeatedly, particularly early in the morning. Poor appetite and weight loss sometimes lead to emaciation, and in women, menstrual periods may stop. However, overeating and weight gain are common in people with mild depression.

Some depressed people complain of having a physical illness, with various aches and pains. Some fear calamity or the possibility of becoming insane. Others think they have an incurable or shameful illness, such as cancer or a sexually transmitted disease, and think they are infecting other people.

Did You Know... Depression involves more than feeling sad all the time. People may feel worthless and guilty, lose interest in their normal pleasures, have sleep disorders, or lose or gain weight.

Suicide: Thoughts of death are among the most serious symptoms of depression. Many depressed people want to die or feel they are so worthless that they should die. As many as 15% of untreated depressed people end their life by suicide. A suicide threat is an emergency (see Suicidal Behavior). When people threaten to kill themselves, a doctor may hospitalize them so that they can be supervised until treatment reduces the risk of suicide. The risk is especially high in the following situations:

• When depression is not treated or is inadequately treated.
• When treatment is started (when people are becoming more active mentally and physically but their mood is still dark)
• When people continue to feel excessively sad even while returning to normal activities
• When people have a significant anniversary
• When people alternate between depression and mania (bipolar disorder—see Mood Disorders: Bipolar Disorder (Manic-Depressive Illness)).
• When people feel very anxious
• When people are drinking alcohol or taking recreational or illicit drugs

Substance Abuse: People with depression are more likely to abuse alcohol or other recreational drugs in an attempt to help them sleep or feel less anxious. However, depression causes alcoholism and drug abuse less often than was once thought. People are also more likely to smoke heavily and to neglect their health. Thus, the risk of developing or worsening other disorders, such as chronic obstructive pulmonary disease, is increased.

Dysthymia: In some depressed people, symptoms are mild, but the disorder lasts for years, often decades. This type of depression, called dysthymia, often begins during adolescence and involves distinct changes in personality. People with dysthymia are gloomy, pessimistic, skeptical, humorless, or incapable of having fun. They are passive, lack energy, and keep to themselves. They constantly complain and are quick to criticize others and reproach themselves. They are preoccupied with inadequacy, failure, and negative events, sometimes to the point of morbid enjoyment of their own failures.

What Is Seasonal Affective Disorder?
Many people report feeling sadder in late autumn and winter, blaming this tendency on the shortening of daylight hours and colder temperatures. However, some people develop a more intense sadness known as seasonal affective disorder, which is a type of depression. Seasonal affective disorder (also called autumn-winter depression) is characterized by recurring episodes of depression that usually begin in October or November and end by February or March. The disorder is more common in extreme northern and southern latitudes, where the winter season is typically longer and harsher. It is believed that seasonal affective disorder may be caused by longer secretion of melatonin (a hormone produced by the pineal gland, which is located in the middle of the brain) that normally occurs at night. Symptoms include lethargy, decreased interest in and withdrawal from usual activities, oversleeping, and overeating. In spring, the symptoms steadily resolve. However, in some people, spring triggers a rapid swing to symptoms that are almost the opposite of those experienced during the winter. These symptoms (called spring-summer hypomania) include increased energy and involvement in activities, decreased need for sleep, and decreased appetite. Phototherapy is the most effective treatment. People are placed in a closed room that is bathed in high levels of artificial light (light levels in a normally-lit room are not adequate). The light is controlled to mimic the season that the therapist is trying to create: longer days for summer and shorter days for winter.

Diagnosis

A doctor is usually able to diagnose depression based on symptoms. A previous history of depression or a family history of depression helps confirm the diagnosis. Excessive worrying, panic attacks, and obsessions are common in depression and may lead the doctor to incorrectly think that the person has an anxiety disorder.

In older people, depression may be difficult to notice, especially if they do not work or have little social interaction. Also, depression may be mistaken for dementia because it can cause similar symptoms. However, symptoms of dementia due to depression resolve when depression is treated. Symptoms of dementia do not.

Standardized questionnaires are used to help identify depression and determine how severe it is. Two such questionnaires are the Hamilton Depression Rating Scale, conducted verbally by an interviewer, and the Beck Depression Inventory, a self-administered questionnaire. Doctors also ask people whether they have any thoughts or plans to harm themselves. Such thoughts indicate that depression is severe.

No test can confirm depression. However, laboratory tests may help a doctor determine whether depression is caused by an endocrine or other physical disorder For example, blood tests are usually done to detect a thyroid disorder or vitamin deficiency. In younger people, tests may be done to detect drug abuse. A thorough neurologic examination is done to check for Parkinson's disease, which causes some of the same symptoms. People who have severely disturbed sleep may need to have testing (polysomnography—see Sleep Disorders: Testing) to distinguish sleep disorders from depression.

Prognosis and Treatment

If untreated, depression may last about 6 months to several years. Although mild symptoms persist in many people, functioning tends to return to normal. However, most people with depression have repeated episodes, averaging 4 to 5 times over a lifetime.

Most people with depression do not require hospitalization. However, some people should be hospitalized, especially if they are contemplating suicide or have attempted it, are frail because of weight loss, or are at risk of heart problems because of severe agitation.

Drug therapy is the cornerstone of treatment. Other treatments include psychotherapy and electroconvulsive therapy. Sometimes a combination of therapies is used. Depression can usually be treated successfully. If a cause (such as a drug or another disorder) can be identified, it is corrected first, but drugs to treat depression may also be needed.

Drug Therapy: Several types of antidepressants—selective serotonin reuptake inhibitors (SSRIs), heterocyclic antidepressants, monoamine oxidase inhibitors (MAOIs), and several new types—are available, as well as psychostimulants. Most must be taken regularly for at least several weeks before they begin to work. The chances that any given antidepressant will work for a particular person are about 65%. Side effects vary with each type of drug. Sometimes when treatment with one drug does not relieve depression, a combination of antidepressant drugs is prescribed.

Selective serotonin reuptake inhibitors (SSRIs) are now the most commonly used class of antidepressants. SSRIs are effective in treating depression and dysthymia as well as other mental health disorders that often coexist with depression. Although SSRIs can cause nausea, diarrhea, tremor, weight loss, and headache, these side effects are usually mild or go away with continued use. Most people tolerate the side effects of SSRIs better than the side effects of heterocyclic antidepressants. SSRIs are less likely to adversely affect the heart than heterocyclic antidepressants. However, a few people may seem more agitated, depressed, and anxious the first week after they start SSRIs or the dose is increased. Some people, especially younger children and adolescents, become increasingly suicidal if these symptoms are not detected and rapidly treated. People taking SSRIs and their loved ones should be warned of this possibility and instructed to call their doctor if symptoms worsen with treatment. However, because people with untreated depression sometimes commit suicide, people and their doctors must balance this risk against the risk of drug treatment. Also, with long-term use, SSRIs may have additional side effects, such as weight gain and sexual dysfunction (in one third of people). Abruptly stopping some of the SSRIs may result in a discontinuation syndrome that includes dizziness, anxiety, irritability, nausea, and flu-like symptoms.

Newer antidepressants are as effective and safe as SSRIs and have similar side effects. These drugs include

• NorepinephrineSome Trade Names
  LEVOPHED
  -dopamine reuptake inhibitors
• Serotonin modulators
• Serotonin-norepinephrineSome Trade Names
  LEVOPHED
  reuptake inhibitors

As may occur with SSRIs, the risk of suicide may be temporarily increased when these drugs are first started, and abruptly stopping serotonin-norepinephrineSome Trade Names
LEVOPHED
reuptake inhibitors may result in a discontinuation syndrome.

Heterocyclic (including tricyclic) antidepressants, once the mainstay of treatment, are now used infrequently because they have more side effects than other antidepressants. They often cause drowsiness and lead to weight gain. They can also cause an increase in heart rate and a decrease in blood pressure when a person stands. Other side effects include blurred vision, dry mouth, confusion, constipation, and difficulty starting to urinate. These other side effects, called anticholinergic effects, are often more severe in older people (see Aging and Drugs: Anticholinergic: What Does It Mean? ). Abruptly stopping heterocyclic antidepressants, as with SSRIs, may result in a discontinuation syndrome.

Monoamine oxidase inhibitors (MAOIs) may be effective but are rarely prescribed except when other antidepressants have not worked. People who use MAOIs must adhere to a number of dietary restrictions and take special precautions to avoid a serious reaction involving a sudden, severe rise in blood pressure with a severe, throbbing headache (hypertensive crisis). This crisis can cause a stroke. Precautions include

• Not eating foods or beverages that contain tyramine, such as beer on tap, red wines (including sherry), liqueurs, overripe foods, salami, aged cheeses, fava or broad beans, yeast extracts (marmite), canned figs, raisins, yogurt, cheese, sour cream, pickled herring, caviar, liver, extensively tenderized meats, and soy sauce
• Not taking pseudoephedrineSome Trade Names
  AFRINOL SUDAFED
  , contained in many over-the-counter cough and cold remedies
• Not taking dextromethorphanSome Trade Names
  DELSYM
  (a cough suppressant), reserpine (an antihypertensive drug), or meperidine (an analgesic)
• Carrying an antidote, such as chlorpromazine tablets, at all times and, if a severe, throbbing headache occurs, taking the antidote at once and going to the nearest emergency room

People who take MAOIs should also avoid taking other types of antidepressants, including heterocyclic antidepressants, SSRIs, bupropionSome Trade Names
WELLBUTRIN
, and serotonin modulators (mirtazapineSome Trade Names
REMERON
, nefazodone, and venlafaxineSome Trade Names
EFFEXOR
). Taking an MAOI with another antidepressant can cause a dangerously high body temperature, breakdown of muscle, kidney failure, and seizures. These effects, called neuroleptic malignant syndrome, can be fatal (see Schizophrenia and Delusional Disorder: What Is Neuroleptic Malignant Syndrome?).

Psychostimulants, such as dextroamphetamineSome Trade Names
DEXEDRINE
and methylphenidateSome Trade Names
CONCERTA METHYLIN RITALIN
, as well as other drugs, are sometimes used, often with antidepressants.

St. John's wort, an herbal dietary supplement, is sometimes used to relieve mild depression, although its effectiveness is not proven. Due to potentially harmful interactions between St. John's wort and many prescription drugs, people interested in taking this herbal supplement need to discuss possible drug interactions with their doctor (see Medicinal Herbs and Nutraceuticals: St. John's Wort).

Psychotherapy: Psychotherapy alone may be just as effective as drug therapy for mild depression. When used with drugs, it can be useful for severe depression.

Individual or group psychotherapy can help people with depression gradually resume former responsibilities and adapt to the normal pressures of life, building on the improvement caused by antidepressants. Interpersonal psychotherapy can provide supportive guidance to people while they adjust to changes in life roles. Cognitive-behavioral therapy can help change hopelessness and negative thinking.

Electroconvulsive Therapy: Electroconvulsive therapy is sometimes used to treat people with severe depression, particularly people who are psychotic, threatening to commit suicide, or refusing to eat. It is also used to treat depression during pregnancy when drugs are ineffective. This type of therapy is usually very effective and can relieve depression quickly, unlike most antidepressants, which can take up to several weeks. The speed with which it takes effect can save lives.

For electroconvulsive therapy, electrodes are placed on the head, and an electrical current is applied to induce a seizure in the brain. For reasons that are not understood, the seizure relieves depression. Usually, at least five to seven treatments, one treatment every other day, are given. Because the electrical current can cause muscle contractions and pain, general anesthesia is required during treatments. Electroconvulsive therapy may cause some temporary memory loss and, rarely, permanent memory loss.

PrintOpen table in new window
Drugs Used to Treat Depression Drug Some Side Effects Comments Heterocyclic (including tricyclic) antidepressants Amitriptyline Amoxapine ClomipramineSome Trade Names ANAFRANIL DesipramineSome Trade Names NORPRAMIN DoxepinSome Trade Names SINEQUAN ZONALON ImipramineSome Trade Names TOFRANIL Maprotiline NortriptylineSome Trade Names AVENTYL ProtriptylineSome Trade Names VIVACTIL TrimipramineSome Trade Names SURMONTIL Drowsiness, weight gain, increased heart rate, decreased blood pressure, dry mouth, confusion, blurred vision, constipation, difficulty starting to urinate, and delayed orgasm With clomipramineSome Trade Names ANAFRANIL and maprotiline, seizures Side effects are usually more pronounced in older people. Overdosage can cause serious, potentially life-threatening toxicity. Selective serotonin reuptake inhibitors (SSRIs) CitalopramSome Trade Names CELEXA EscitalopramSome Trade Names LEXAPRO FluoxetineSome Trade Names PROZAC FluvoxamineSome Trade Names LUVOX ParoxetineSome Trade Names PAXIL SertralineSome Trade Names ZOLOFT Sexual dysfunction (primarily, delayed orgasm but also loss of desire in some people), nausea, diarrhea, headache, weight loss (short-term), weight gain (long-term), discontinuation syndrome,* forgetfulness, blunting of emotions, and easy bruising SSRIs are the most commonly used class of antidepressants. They are also effective for dysthymia, generalized anxiety disorder, obsessive-compulsive disorder, panic disorder, phobic disorder, posttraumatic stress disorder, premenstrual dysphoric disorder, and bulimia. Toxicity due to overdosage is less serious than that with other antidepressants. Monoamine oxidase inhibitors (MAOIs) IsocarboxazidSome Trade Names MARPLAN PhenelzineSome Trade Names NARDIL SelegilineSome Trade Names ELDEPRYL TranylcypromineSome Trade Names PARNATE Insomnia, nausea, weight gain, sexual dysfunction (loss of desire and delayed orgasm), pins-and-needles sensation, dizziness, insomnia, lowered blood pressure (particularly when a person stands), and severe high blood pressure People who take these drugs must follow dietary restrictions and avoid using certain drugs. SelegilineSome Trade Names ELDEPRYL is available as a patch. With the patch, people do not have to follow the dietary restrictions unless the patch contains a high dose. Psychostimulants DextroamphetamineSome Trade Names DEXEDRINE MethylphenidateSome Trade Names CONCERTA METHYLIN RITALIN Nervousness, tremor, insomnia, and dry mouth These drugs are usually used with antidepressants. Used alone, they are usually ineffective as antidepressants. Serotonin modulators (5-HT2 blockers) MirtazapineSome Trade Names REMERON Drowsiness and weight gain MirtazapineSome Trade Names REMERON does not cause nausea or sexual dysfunction. Nefazodone Mild drowsiness and, rarely, serious liver problems Nefazodone produces restful sleep. Trazodone Prolonged drowsiness, painful and persistent erection (priapism), and an excessive decrease in blood pressure when a person stands Serotonin-norepinephrineSome Trade Names LEVOPHED reuptake inhibitors DuloxetineSome Trade Names CYMBALTA Nausea, dry mouth, discontinuation syndrome,* and, if high doses are taken, an increase in blood pressure Most of the side effects can be prevented or minimized when low doses are used and when changes in dosages are made slowly. VenlafaxineSome Trade Names EFFEXOR NorepinephrineSome Trade Names LEVOPHED -dopamine reuptake inhibitors BupropionSome Trade Names WELLBUTRIN Headache, agitation, discontinuation syndrome,* high blood pressure in a few people, and rarely seizures BupropionSome Trade Names WELLBUTRIN is useful for depressed people who also have attention-deficit/hyperactivity disorder or cocaine dependence and those trying to stop smoking. BupropionSome Trade Names WELLBUTRIN does not cause sexual dysfunction. *Discontinuation syndrome consists of dizziness, anxiety, irritability, nausea, and flu-like symptoms that occur when a drug is stopped abruptly. Drugs Used to Treat Depression Drug Some Side Effects Comments Heterocyclic (including tricyclic) antidepressants Amitriptyline Amoxapine ClomipramineSome Trade Names ANAFRANIL DesipramineSome Trade Names NORPRAMIN DoxepinSome Trade Names SINEQUAN ZONALON ImipramineSome Trade Names TOFRANIL Maprotiline NortriptylineSome Trade Names AVENTYL ProtriptylineSome Trade Names VIVACTIL TrimipramineSome Trade Names SURMONTIL Drowsiness, weight gain, increased heart rate, decreased blood pressure, dry mouth, confusion, blurred vision, constipation, difficulty starting to urinate, and delayed orgasm With clomipramineSome Trade Names ANAFRANIL and maprotiline, seizures Side effects are usually more pronounced in older people. Overdosage can cause serious, potentially life-threatening toxicity. Selective serotonin reuptake inhibitors (SSRIs) CitalopramSome Trade Names CELEXA EscitalopramSome Trade Names LEXAPRO FluoxetineSome Trade Names PROZAC FluvoxamineSome Trade Names LUVOX ParoxetineSome Trade Names PAXIL SertralineSome Trade Names ZOLOFT Sexual dysfunction (primarily, delayed orgasm but also loss of desire in some people), nausea, diarrhea, headache, weight loss (short-term), weight gain (long-term), discontinuation syndrome,* forgetfulness, blunting of emotions, and easy bruising SSRIs are the most commonly used class of antidepressants. They are also effective for dysthymia, generalized anxiety disorder, obsessive-compulsive disorder, panic disorder, phobic disorder, posttraumatic stress disorder, premenstrual dysphoric disorder, and bulimia. Toxicity due to overdosage is less serious than that with other antidepressants. Monoamine oxidase inhibitors (MAOIs) IsocarboxazidSome Trade Names MARPLAN PhenelzineSome Trade Names NARDIL SelegilineSome Trade Names ELDEPRYL TranylcypromineSome Trade Names PARNATE Insomnia, nausea, weight gain, sexual dysfunction (loss of desire and delayed orgasm), pins-and-needles sensation, dizziness, insomnia, lowered blood pressure (particularly when a person stands), and severe high blood pressure People who take these drugs must follow dietary restrictions and avoid using certain drugs. SelegilineSome Trade Names ELDEPRYL is available as a patch. With the patch, people do not have to follow the dietary restrictions unless the patch contains a high dose. Psychostimulants DextroamphetamineSome Trade Names DEXEDRINE MethylphenidateSome Trade Names CONCERTA METHYLIN RITALIN Nervousness, tremor, insomnia, and dry mouth These drugs are usually used with antidepressants. Used alone, they are usually ineffective as antidepressants. Serotonin modulators (5-HT2 blockers) MirtazapineSome Trade Names REMERON Drowsiness and weight gain MirtazapineSome Trade Names REMERON does not cause nausea or sexual dysfunction. Nefazodone Mild drowsiness and, rarely, serious liver problems Nefazodone produces restful sleep. Trazodone Prolonged drowsiness, painful and persistent erection (priapism), and an excessive decrease in blood pressure when a person stands Serotonin-norepinephrineSome Trade Names LEVOPHED reuptake inhibitors DuloxetineSome Trade Names CYMBALTA Nausea, dry mouth, discontinuation syndrome,* and, if high doses are taken, an increase in blood pressure Most of the side effects can be prevented or minimized when low doses are used and when changes in dosages are made slowly. VenlafaxineSome Trade Names EFFEXOR NorepinephrineSome Trade Names LEVOPHED -dopamine reuptake inhibitors BupropionSome Trade Names WELLBUTRIN Headache, agitation, discontinuation syndrome,* high blood pressure in a few people, and rarely seizures BupropionSome Trade Names WELLBUTRIN is useful for depressed people who also have attention-deficit/hyperactivity disorder or cocaine dependence and those trying to stop smoking. BupropionSome Trade Names WELLBUTRIN does not cause sexual dysfunction. *Discontinuation syndrome consists of dizziness, anxiety, irritability, nausea, and flu-like symptoms that occur when a drug is stopped abruptly.

Last full review/revision June 2008 by Jan Fawcett, MD