What are mood disorders

Mood disorders are considered to be associated with a disturbance in mood which is recognized as the primary symptom presentation. It is estimated that about 20% of the U.S. population report to having at least on depressive symptoms in a given month and 12% report to having two or more in a given year The symptoms of a mood disorder can range from inappropriate, exaggerated, or a limited range of feelings. Disorders that are found in this category include major depressive disorder, cyclothymic disorder, dysthymic disorder, and bipolar disorder. These disorders are grouped together in the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV.TR)

How are mood disorders diagnosed

American Psychiatric Association guidelines state that in order for individuals to be diagnosed with a mood disorder the feeling must exist on an extreme level such as frequent occurrence of a depressed feeling or suicidal thoughts. On the other spectrum having excessive energy (bipolar disorder) without sleeping for many days at a time and taking on many endless tasks or activities is also used for diagnosis. A confirmation of depression can be if there is at least 5 symptoms of depression during the same 2-week period and one of these symptoms include either a depressed mood or diminished interest or pleasure.

How are mood disorders treated

Antidepressant therapies can be an effective approach to treating mood disorders but there are similarities as well as differences that influence the selection of one over another. When it comes to prescribing antidepressants it is important to determine whether there are sustained psychological symptoms that meet the criteria for the mood disorder.

What drugs are used for treating depression

Antidepressants are generally used when individuals exhibit symptoms or voice depressive symptoms. The treatment of major depression can consist of selective serotonin reuptake inhibitors (SSRI), selective serotonin and norepinephrine reuptake inhibitors (SNRI), tricyclic antidepressants, norepinephrine and dopamine inhibitors, serotonin-2 antagonist reuptake inhibitors, and monoamine oxidase inhibitors (MAOI).

What are the differences between antidepressants

All antidepressant drugs have shown equal efficacy but the various agents have different side-effect profiles that may lead to the selection of one over another. Monoamine oxidase inhibitors were one of the first agents to be used for depression but are rarely used today due to their side effects such as orthostatic hypotension, insomnia, urinary hesitancy, constipation, and weight gain. They can also cause serotonin syndrome when combined with other antidepressants or serotonergic agents or hypertensive crisis when combined with tyramine-containing foods such as aged cheese or wine. Monoamine oxidase inhibitors inhibit monoamine oxidase in various organ with the greatest effect being observed on monoamine oxidase A (MAO-A) whose primary substrates are norepinephrine and serotonin and MAO-B which acts primarily on other amines.

The selective serotonin reuptake inhibitors (SSRIs) selectively block the reuptake of serotonin through their inhibition of the sodium-potassium adenosine triphosphatase (ATPase)-dependent serotonin transporter and are considered to be one of the much safer agents because of their low lethality with overdose, ease of administration, and a more tolerable side effect profile. The risk of drug interaction is generally limited with the SSRIs but serotonin syndrome, the most serious interaction, can occur if combined with monoamine oxidase inhibitors. Another potential drug interaction results from SSRIS inhibiting enzymes of the cytochrome P450 system. On the other hand the tricyclic antidepressants which act by inhibiting the reuptake of serotonin and norepinephrine can cause arrhythmias, hypotension, or uncontrollable seizure with overdose and should not be used in a person with a history of cardiac disease. Acute doses of 1 gram of tricyclic antidepressants are often toxic and/or fatal. Serum levels of tricyclic antidepressants that have established therapeutic ranges (nortriptyline, imipramine, amitriptyline) can also be used to monitor overdose. These agents should be avoided in individuals who have expressed suicidal thoughts and/or behaviors.

How are antidepressants selected

The selective serotonin reuptake inhibitors are typically used first because they are regarded as one of the safest antidepressant, have comparatively better side-effect profiles, and require less time for dose titration. Selection of an antidepressant is normally based on a person’s tolerance to the side effects, age, suicide potential, and coexisting diseases and medication.

References

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