What are antidepressants?

Antidepressants are medications used for the treatment of depression.  People with depression are often treated with antidepressant drugs along with psychotherapy in order to help them get better and cope with this debilitating condition.

What is depression?

Depression is a serious medical condition caused by a brain disorder that can impair one's ability to function in everyday situations.  Depression profoundly impairs the ability to function in everyday situations by affecting moods, thoughts, behaviors, and physical well-being.

What types of depression are there?

There are several types of depression. The most common types are major depressive disorder and dysthymic disorder.

Major depressive disorderis also known as major depression.  This type of depression is characterized by a combination of symptoms that interfere with a person's bility to work, sleep, study, eat, and enjoy once–pleasurable activities.

Major depression is disabling and prevents a person from functioning normally. An episode of major depression may occur only once in a person's lifetime, but more often, it recurs throughout a person's life.

Dysthymic disorderis also known as dysthymia.  This type of depressive disorder is characterized by long–term (two years or longer) but less severe symptoms that may not disable a person but can prevent one from functioning normally or feeling well. People with dysthymia may also experience one or more episodes of major depression during their lifetimes.

Other types of depressive disorder include:

Psychotic depression, which occurs when a severe depressive illness is accompanied by some form of psychosis, such as a break with reality, hallucinations, and d elusions.

Postpartum depression, which is diagnosed if a new mother develops a major depressive episode within one month after delivery. It is estimated that 10 to 15 percent of women experience postpartum depression after giving birth.1

Seasonal affective disorder (SAD), which is characterized by the onset of a depressive illness during the winter months, when there is less natural sunlight. The depression generally lifts during spring and summer. SAD may be effectively treated with light therapy, but nearly half of those with SAD do not respond to light therapy alone. Antidepressant medication and psychotherapy can reduce SAD symptoms, either alone or in combination with light therapy.2

Bipolar disorder, also called manic-depressive illness, is not as common as major depression or dysthymia. Bipolar disorder is characterized by cycling mood changes-from extreme highs (e.g., mania) to extreme lows (e.g., depression).

What are the signs and ymptoms of depression?

Symptoms of depression include:

  • Persistent sad, anxious or "empty" feelings
  • Feelings of hopelessness and/or pessimism
  • Feelings of guilt, worthlessness and/or helplessness
  • Irritability, restlessness
  • Loss of interest in activities or hobbies once pleasurable, including sex
  • Fatigue and decreased energy
  • Difficulty concentrating, remembering details and making decisions
  • Insomnia, early–morning wakefulness, or excessive sleeping
  • Overeating, or appetite loss
  • Thoughts of suicide, suicide attempts
  • Persistent aches or pains, headaches, cramps or digestive problems that do not ease even with treatment

How do antidepressants work?

Antidepressant medications work by altering (in various ways depending on the type of antidepressant) the brains natural chemicals known as neurotransmitters.  A neurotransmitter is achemical that is made by nerve cells and used to communicate with other cells, including other nerve cells and muscle cells.  It is disruptions in the production of, or the cell’s utilization of, neurotransmitters that leads to depression.   Antidepressant drugs help to “rebalance” the neurotransmitters in the brain.

What types of antidepressant drugs are there?

There are several types of antidepressant medications.  The most common types of antidepressants used in the treatment of depression include:

  • Selective serotonin reuptake inhibitors (SSRI)
  • Serotonin-norepinephrine reuptake inhibitors (SNRI)
  • Monoamine oxidase inhibitors (MAOIs)
  • Tricyclic antidepressants (TCAs)
  • What are the antidepressant side effects?

There are many side effects caused by antidepressants.  The specific side effects depend not only on the particular type of antidepressant but also on the specific drug being taken.  For a more complete list of side effects please click on a particular drug from the list above and review the drug information provided for that specific drug.

Some of the various side effects from the different antidepressants are: 

  • Dry mouth
  • Urinary retention
  • Blurred vision
  • Constipation
  • Sedation (can interfere with driving or operating machinery)
  • Sleep disruption
  • Weight gain
  • Headache
  • Nausea
  • Gastrointestinal disturbance/diarrhea
  • Abdominal pain
  • Inability to achieve an erection
  • Inability to achieve an orgasm (men and women)
  • Loss of libido
  • Agitation
  • Anxiety
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