Atypical Depression

Atypical depression -- a type of depression that can be difficult to treat - has symptoms that include weight gain, sleeping too much, and feeling anxious. Here is information about the causes of atypical depression and its diagnosis that you can use to help you talk with your doctor about it.

What is atypical depression?

Atypical depression is a subtype of depression with certain specific characteristics. A person with classic clinical depression has at least five, and possibly more, of the following symptoms or signs:

* sadness

* loss of energy

* feelings of hopelessness or worthlessness

* loss of enjoyment in things that were once pleasurable

* difficulty concentrating

* uncontrollable crying

* difficulty making decisions

* irritability

* increased need for sleep

* insomnia or excessive sleep

* unexplained aches and pains

* stomachache and digestive problems

* decreased sex drive

* sexual problems

* headache

* a change in appetite that causes weight loss or gain

* thoughts of death or suicide

* attempting suicide

In general, people with atypical depression don't have as many of the symptoms that people with classical depression may have. They also tend to have first experienced depression at an early age, during their teenage years.

Despite its name, atypical depression is probably rather common. Some doctors believe that it is underdiagnosed. Researchers are considering whether or not atypical depression might be a type of dysthymia -- a low-level depression that has lingered for at least two years. Researchers are also investigating the idea that atypical depression may be a milder form of bipolar disorder called cyclothymia. People with cyclothymia typically have less extreme switches in mood.

What are the symptoms of atypical depression?

The main characteristic of atypical depression that distinguishes it from major depression is mood reactivity. In other words, the person with atypical depression will see his or her mood improve if something positive happens. In major, or melancholic, depression, positive changes will not bring on a change in mood. In addition, diagnostic criteria call for at least two of the following symptoms to accompany the mood reactivity:

* sleeping too much (hypersomnia)

* eating too much (hyperphagia), resulting in weight gain

* having a more intense reaction or increased sensitivity to rejection, resulting in problems with social and work relationships

* having a feeling of being weighed down, paralyzed, or "leaden"

A doctor will investigate physical causes for any of these symptoms. That includes doing blood tests for thyroid problems or hormone levels. Atypical depression can co-exist with other diseases. For example, it might occur with hypothyroidism -- low levels of thyroid hormone -- which has symptoms that include depression and weight gain. Studies have also shown that atypical depression has been found in some people with adult-onset human growth hormone deficiency.

What causes atypical depression?

Depression is believed to be the result of a chemical imbalance in the brain. These chemicals -- neurotransmitters that facilitate communication between brain cells -- include dopamine, serotonin, and norepinephrine. While the exact cause of depression is unknown, there are risk factors for depression, including:

* a family history of depression

* a significant loss -- from death, divorce, or separation -- that results in grief

* interpersonal conflicts and related emotions such as guilt

* any type of abuse -- physical, sexual, or emotional

* any type of major life event such as moving, changing or losing a job, graduating, retiring

* any type of serious illness such as cancer, heart disease, stroke, or HIV

* drug or alcohol abuse

* isolation or exclusion from family, friends, or other social groups

How is atypical depression treated?

Doctors are likely to prescribe antidepressants as the treatment for atypical depression. One of the reasons that atypical depression is believed to exist as a distinct condition is that it generally responds better to monoamine oxidase inhibitors (MAOIs) and selective serotonin reuptake inhibitors (SSRIs). Unlike typical depression, atypical depression does not respond as well to an older class of drugs, tricyclic antidepressants (TCAs).

While MAOIs are effective at treating atypical depression, doctors are not likely to prescribe one as a first attempt to treat any type of depression. That's because MAOIs can have adverse drug and food interactions. People taking MAOIs are expected to follow a special diet for atypical depression. In addition to the usual cautions to limit simple carbohydrates and fat, people taking MAOIs must also limit or avoid foods and drinks that contain tyramine. Tyramine acts to inhibit monoamine oxidase, an amino acid that neutralizes the effects of tyramine in the body. Food and drink items that are believed to contain tyramine include:

* aged cheeses -- cottage cheese and cream cheese are thought to be safe

* processed meats, such as pepperoni, salami, pastrami, summer sausage, and mortadella

* any improperly stored foods and any foods refrigerated longer than 2 weeks

* any combination food -- like pizza -- that may include foods with tyramine

* sauerkraut

* beer on tap

* fermented soy products, including soy sauce, teriyaki sauce, tempeh, bean paste, and miso soup

* Marmite and Vegemite yeast extract spreads

* fava bean or broad bean pods

* banana peels

Alcohol consumption should be minimal -- 4 ounces of wine, 12 ounces of bottled or canned beer, or 1 and 1/2 ounce of liquor -- or simply avoided altogether.

In addition to interacting with food items, MAOIs interact with many over-the-counter and prescription drugs. Categories that are especially fraught with problems include:

* drugs for diet or weight reduction

* drugs for sinus, hay fever, or cold relief

* nose sprays or drops

* inhaled drugs or tablets for asthma

* cough medicines

* herbal stimulants, such as ephedra (ma huang) or ginseng

It might also be wise to keep caffeine consumption down.

The food and drug restrictions must be followed while taking the MAOI and for three to four weeks after you stop taking it. High levels of tyramine in your body can cause potentially serious reactions, including:

* confusion

* headaches

* heart problems

* high blood pressure (hypertension)

* nausea and/or vomiting

* restlessness

* visual disturbances

Examples of MAOI drugs include selegiline (EmSam Patch), isocarboxzaid (Marplan), phenelzine (Nardil), and tranylcypromine (Parnate).

What other approaches to treatments might be used for atypical depression?

People who have atypical depression and other diseases, such as hypothyroidism or growth hormone deficiency, may find that hormone treatment or other additional treatment improves symptoms. In addition, combinations of antidepressants and anxiety medicines, such as benzodiazepines, may be prescribed for depression and anxiety-related depression. Benzodiazepines must be used with caution in some patients due to the potential for abuse.

Due to the restrictions associated with MAOIs, doctors are usually likely to prescribe selective serotonin reuptake inhibitors (SSRIs). These drugs work to increase the levels of serotonin in the brain. Other newer drugs may work on the levels of both serotonin and norepinephrine. Examples of SSRIs include:

* fluoxetine (Prozac)

* sertraline ( Zoloft)

* paroxetine (Paxil)

* escitalopram ( Lexapro)

* fluvoxamine (Luvox)

* citalopram (Celexa)

People who are prescribed MAOIs after taking an SSRI must wait five weeks before beginning the new medication. That's because of the potential for adverse drug interaction, including death. Side effects of SSRIs may include:

* withdrawal symptoms

* increased sensitivity to the sun ( photosensitivity)

* low blood sugar

* rash

* drowsiness

* impaired kidney or liver function