the biogenic amine theory of depression.
In other words, deficiency of monoamines such as nor-epi or serotonin in parts of the brain can result in depression whereas excess amounts may result in the affective disorder known as mania.
however, antidepressant therapy generally increases amine levels in the brain for days to weeks before actual therapeutic benefits are gained.
Antidepressant uses
Antidepressant side effects
All of the antidepressants have a potential for lowering the threshold for seizure activity especially when alcohol is being consumed.
All of the antidepressants have the potential of causing an increase in suicidal thinking and suicidal behavior.
Antidepressant categories
Monoamine oxidase inhibitors examples
**outdated, most side effects, lethal
Monoamine oxidase inhibitors (MAOI)
foods and tyramine
• Tyramine, an amino acid in humans, belongs to the amine family and as such is normally broken down by monoamine oxidase.
cheese (especially aged cheeses), soy products (especially when fermented), certain dried fruits such as raisins, meats and in red wine.
Since gastrointestinal MAO is essential for the adequate breakdown of tyramine, anyone using MAO inhibitors should avoid foods with high levels of tyramine–>serotonin syndrome
Monoamine oxidase inhibitors and crazy SE
Tricyclic antidepressants MOA and uses
• The exact mechanism of action of this class of drugs is not known. Diminishing the reuptake of monoamine neurotransmitters is clearly one of the chief effects.
Subsequent down regulation of postsynaptic receptors may be the true mechanism of action.
• Tricyclic are used to treat obsessive compulsive disorders, enuresis, panic attacks, chronic pain and migraine headaches as well as depression. Insomnia.
The medication is usually taken at bedtime because of sedating side effects.
Tricyclic antidepressants (TCAs) examples
• Amitriptyline/ Elavil • Amoxapine/ Asendin • Clomipramine/ Anafranil • Doxepin/ Doxepin • Desipramine/ Norpramine • Imipramine/ Tofranil • Nortriptyline/ Pamelor • Protriptylene/ Vivactil 
Tricyclic antidepressants SE
!!!potentially cardiotoxic and should be avoided in susceptible individuals with heart disease. Dysrythmias, torsade de pointes!!
In contrast to the SSRIs, the cyclic antidepressants can be fatal in doses as little as 10 times the daily dose.
• The toxicity is usually due to prolongation of the QT interval, leading to arrhythmias.
Amitriptyline/ Elavil
Amitriptyline/ Elavil SE
•TCA
Side effects: Dizziness and marked drowsiness. Anticholinergic effects such as dry mouth, constipation, urinary hesitancy and blurred vision. Stopping treatment abruptly cause withdrawal-like symptoms i.e. nausea, headache, dizziness, lethargy, and flu-like symptoms. This is referred to as discontinuation syndrome.
Tetracyclic antidepressants
Selective serotonin reuptake inhibitors (SSRIs)
SSRIs have been documented to be helpful in 50% to 70% of patients with major depression.
Selective serotonin reuptake inhibitors SE
Selective serotonin reuptake inhibitors examples
Fluoxetine/ Prozac class, idnication, MOA
*The FDA states that Paxil should be avoided in children and teens and that in cases of pediatric cases of depressive disorder the antidepressant drug to be used is Prozac.
Fluoxetine/ Prozac char, SE
SSRIs and sexual dysfunction
Sexual dysfunction is a very common side-effect, especially with SSRIs. Common sexual side-effects include problems with sexual desire, lack of interest in sex, and anorgasmia (trouble achieving orgasm). Although usually reversible, these sexual side-effects can, in rare cases, last for months or years after the drug has been completely withdrawn. This is known as Post SSRI Sexual Dysfunction.SSRI-induced sexual dysfunction affects 30% to 50% or more of individuals who take these drugs for depression.
Fluoxetine/ Prozacdrug interactions
• Painkillers of the NSAIDs drug family may interfere and reduce the efficiency of SSRIs and may compound the increased risk of gastrointestinal bleeds caused by SSRI use. These agents include:
Serotonin and norepinephrine reuptake inhibitors (SNRIs) examples
Duloxetine/ Cymbalta

Duloxetine/ Cymbalta SE
The most common side effects include headache, somnolence, fatigue, nausea, xerostomia, insomnia and erectile dysfunction.
• Black box warning as previously noted: Antidepressants increase the risk of suicidal thinking and behavior in children, adolescents, and young adults (18-24 years of age) with major depressive disorder (MDD) and other psychiatric disorders.