Antidepressants

=__//Antidepressants//__= toc Antidepressants are medications prescribed by psychiatrists and physicians to treat depression. Aside from depression, they may be used for anxiety disorders, bipolar disorder, or eating disorders. Different classifications of antidepressants exists including selective serotinin reuptake inhibitors, tricylic antidepressants, and m onoamine oxidase inhibitor. Amongst all the drugs in the country, antidepressants are the most widely prescribed. They work to help restore balance among neurtoransmitters in the brain.

__Commonly Prescribed Antidepressants__

 * Sertraline - (Zoloft)[[image:zoloft.jpg width="233" height="162" align="right"]]
 * Escitalopram - (Lexapro)
 * Fluoxetine - (Prozac)
 * Bupropion - (Wellbutrin or Zyban)
 * Paroxetine - (Paxil)
 * Venlafaxine - (Effexor)
 * Trazodone - (Desyrel)
 * Amitriptyline (Elavil)
 * Citalopram - (Celexa)
 * Duloxetine - (Cymbalta)
 * Mirtazapine - (Remeron)
 * Nortriptyline - (Pamelor)
 * Imipramine - (Tofranil)[[image:antidepressant.gif width="321" height="411" align="right" caption="photo courtesy of howstuffworks,com"]]

__Side Effects of Antidepressants__

 * Dry Mouth
 * Urinary Retention
 * Blurred Vision
 * Constipation
 * Sedation
 * Sleep Disruption
 * Weight Gain
 * Headache
 * Nausea
 * Abdominal Pain
 * Agitation
 * Anxiety

= = = = = = = = = = = = = = =__Depression__= //"Depression cannot be described any longer as a simple disorder of the brain" - Institute of Psychiatry (UK)//

Depression, a pyschiatric disorder, causes an incessant low mood, a loss of interest in usual activities, and an inability to experience pleasure. An imbalance in the brain is no longer pinpointed as the reason of the disorder, rather as a result. Low serotinin levels are believed to be caused by depression instead of being the other way around. Because of the belief that depression was caused by an imbalance of the brain, antidepressants correct the symptons instead of treat the cause.

__Signs of Depression:__

 * Exhaustion on waking
 * Disrupted sleep, sometimes through upsetting dreams
 * Early morning waking and difficulty getting back to sleep
 * Doing less of what they used to enjoy
 * Difficulty concentrating during the day
 * Improved energy as the day goes on
 * Anxious worrying and intrusive upsetting thoughts
 * Becoming emotional or upset for no particular reason
 * Shortness of temper, or irritability

__Causes of Depression__
Three causes of depression have been identified:
 * Depression is a medical disease, caused by a neurochemical or hormonal imbalance.
 * Depression is caused by certain styles of thinking.
 * Depression is a result of unfortunate experiences.

Serotinin
Serotonin is a neurotransmitter. This links brain cells and controls the way the different sections of the brain communicate with each other. Only 2% of the body’s serotonin is in the brain. The rest is elsewhere in the gut and blood cells. Any drugs that reduce the amount of serotonin in your body have been known to lead to depression. There are some antidepressants that have serotonin in them also. Norepinephrine is one of them.

Noradrenaline
Noradrenaline which is also known as Norepinephrine is a drug that is released by the nerve cells. This is often referred to as the “fight or flight” chemical. This drug is an antidepressant and is responsible for the way the body reacts to stressful situations. Noradrenaline stimulates receptors in the body called alpha receptors. The result is narrowing in the blood vessels. This forces the blood to go to the essential organs like the heart and produce greater resistance for the heart to beat increasingly during pressure. This drug is used to keep blood pressure at normalcy during emergencies and/or stressful situations.

=__Dopamine__= Dopamine is a main neurotransmitter found in the brain. It is made up of five different dopamine receptors: D1, D2, D3, D4, and D5. Dopamine can occur in different parts of the brain and is also a neuro hormone. Dopamine's main behaviors include movement, pleasure, cognition, and motivation. As a neurohormone its main function is to release prolactin from the anterior lobe of the pituitary. Dopmaine is classified as a catecholamine and is formed by the decarboxylation of dopa. Dopa is what is mainly used to treat Parkinsons Disease.

When Dopamine is released it produces feelings of satisfaction, such as when eating food. This is why when over repeated times people repeat tasks which require the release of Dopamine, such as eating even when their bodies aren't really hungry. This idea is the same as with someone who is addicted to cocaine, but in a much more severe way.

= = =__Dopamine and Cocaine Addiction__= When someone becomes addicted to cocaine its chemical naturally inhibits the dopamine cycle. In a person who does not use cocaine the dopamine that is released is eventually recycled back into the dopamine transmitting neuron. With someone who uses cocaine the cocaine binds to the dopamine causing it to not be recycled back to the transmitting neuron. This causes the dopamine to flood the central neural area for 30 minutes and after leaves the user feeling like they did before leading to addiction. This causes this person to constantly want this feeling, but the difference is that dopamine is only released when something pleasurable happens that is still unexpected.



__Selective Serotinin Reuptake Inhibitors__
Selective Serotonin Reuptake Inhibitors are the class of antidepressants used in treating depression. The SSRI increase the extracellular level of the neurotransmitter which inhibits reuptake in the presynaptic cell and finally increases the level of serotonin allowed to bind to the postsynaptic receptor.
 * citalopram - (Celexa)
 * escitalopram - (Lexapro)
 * fluoxetine - (Prozac)
 * paroxetine - (Paxil, Pexeva)
 * sertraline - (Zoloft)

__Tricylic Antidepressants Monoamine Oxidase Inhibitors__
Tricylic Antidepressants are the oldest type of treatment for depression and block certain neurotransmitters such as norepinephrine and serotonin. These types of antidepressnats are less common now that more advanced and safer drugs.
 * amitriptyline - (Elavil) 
 * desipramine - (Norpramin) 
 * imipramine - (Tofranil)
 * nortriptyline - (Aventyl, Pamelor)

__Seratonin and Norepinephrine Reuptake Inhibitors__
These typs of antidepressants are a newer form of antideppresants.
 * venlafaxine - (Effexor)
 * duloxetine - (Cymbalta)

__Norepinephrine and Dopamine Reputake Inhibitors__
Designed to inhibit the neuronal reputake of dopamine and norpinephrine.
 * bupropion - (Wellbutrin)[[image:http://farm1.static.flickr.com/105/260113920_6eef21c0f2.jpg?v=0 width="165" height="136" align="right"]]

__Combined Reuptake Inhibitors and Receptors Blockers__

 * trazodone - (Desyrel)
 * nefazodone - (Serzone)
 * maprotiline
 * mirtazpine - (Remeron)

__Monamine Oxidase Inhibitors__
These work to block the enzyme monamine oxidase, which usually breaks down dopamine, serotonin, and norepinephrine.
 * isocarboxazid - (Marplan)
 * phenelzine - (Nardil)
 * tranlcypromine - (Parnate)