Depression is feeling sad or down for a long period of time, usually 3 months or more. Antidepressants are medications used for the treatment of depression. They correct the imbalance of certain chemicals in the brain to improve symptoms of depression. There are several main classes of medications used for the treatment of depression.
Tricyclics and Tetracyclics Antidepressants (TCAs)
TCAs include maprotiline (Ludiomil) and mirtazapine (Remeron). The tricyclic antidepressants include amitriptyline (Elavil), clomipramine (Anafranil), doxepin (Sinequan), imipramine (Tofranil), trimipramine (Surmontil), desipramine (Norpramin), nortriptyline (Pamelor), protriptyline (Vivactil) and amoxipine. These medications work by blocking the reabsorption (reuptake) of two chemicals, serotonin and norepinephrine; a third chemical, called dopamine, is also blocked but to a much smaller extent. These chemicals are linked to depression and anxiety; TCAs block their action on the body, elevating the mood and improving symptoms of depression and anxiety. According to "Pharmacotherapy: A Pathophysiologic Approach," TCAs are effective in treating all depressive disorders, but their use has diminished due to the availability of equally effective therapies that are safer and cause fewer side effects.
Selective Serotonin Reuptake Inhibitors (SSRIs)
The SSRIs include fluoxetine (Prozac), fluvoxamine (Luvox), paroxetine (Paxil), sertraline (Zoloft), citalopram (Celexa), and ezcitalopram (Lexapro). SSRIs block the reuptake of serotonin, causing an improvement in mood. The SSRIs are equal to the TCAs in treating individuals with major depression. They also cause minimal sedation or extreme sleepiness, dry mouth or constipation. The SSRIs display the most sexual dysfunction problems. Paroxetine causes the least risk of seizures and causes the most weight gain of all antidepressants.
Serotonin Norepinephrine Reuptake Inhibitors
The SNRIs are widely used due to their higher efficacy when compared to TCAs and SSRIs. The SNRIs are venlafaxine (Effexor) and the active form desvenlafaxine (Pristiq), duloxetine (Cymbalta) and milnacipran (Savella). SNRIs act by blocking the reuptake of serotonin and norepinephrine, leading to alleviation of the symptoms of depression and anxiety.
Other Antidepressants
Trazodone and nefazodone are classified as triazolopyridines and are effective in treating major depressive disorders. They inhibit the reuptake of serotonin and improve symptoms of depression. Trazodone displays fewer side effects, such as sedation and dizziness, and is available as an alternative better-tolerated agent. Buproprion, or Wellbutrin, is the only drug classified as an aminoketone and has little effect on serotonin and norepinephrine. It works by blocking dopamine and elevating the mood. It also displays the least amount of problems with sexual dysfunction.
References
- "Pharmacotherapy: A Pathophysiologic Approach"; Joseph T. DiPiro, Rovert L. Talbert, et al; 2008
- "Drug Information Handbook, 15th Edition"; Charles F. Lacy, RPh, PharmD, FCSHP; Lora L. Armstrong, RPh, PharmD, BCPS; et al; 2006
