Download Journal about antidepressant drugs U.N 42904891 Date:18

Journal about antidepressant drugs
U.N 42904891
Date:18 -05-1433
Introduction:
In this journal I will talk about antidepressants is psychiatric medication which is the most
prescribed therapy for depression ,also I will talk how do antidepressants work. ,I will talk
what the classifications of antidepressants drugs, I will explain the first generation of
classification and SAR, side effect of this classification , I will show conclusion what
understand of this classification.
Body
An antidepressants are medications that are used to treat depression by improving symptoms
such as mood, sleep, appetite and concentration. They were first developed in the 1950s. Most
typical antidepressants have a delayed onset of action (2–6 weeks) and are usually
administered for anywhere from months to years. antidepressants are often used to treat other
conditions, such as anxiety disorders, obsessive compulsive disorder,
How antidepressant works :
antidepressants work by increasing the activity of certain chemicals work in our brains called
neurotransmitters After a nerve impulse has been carried across the synapse by a
neurotransmitter like serotonin the neurotransmitter is either broken down by enzymes and
removed or taken back up again into the nerve ending and recycled for future use - a process
known as re-uptake. Many of the main antidepressants work by blocking this recycling
process. Antidepressants such as (fluoxetine) and (paroxetine) are known as SSRIs -standing for Selective Serotonin Reuptake Inhibitors.
Classification of antidepressants drugs:
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Selective serotonin reuptake inhibitors (SSRI antidepressants)
Serotonin norepinephrine reuptake inhibitors (SNRI antidepressants)
Tricyclic antidepressants (tricyclics)
Monoamine oxidase inhibitors (MAOIs),
Others: Selective noradrenergic reuptake inhibitors (NARIs), Selective serotonine
uptake inhibitor and 5HT2A antagonis, , alpha- 2 agonist
1-Monoamine oxidase inhibitors (MAOIs)
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Monoamine oxidase inhibitors (MAOIs) are older antidepressants (first-generation).
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usually are not the first medicines given for depression, because they have serious side effects
when combined with certain foods and or medicines
Monoamine oxidase inhibitors (MAOIs) are usually given to people with depression who:
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Did not get better with other antidepressants.
Cannot tolerate the side effects of other antidepressants.
Have a family or personal history of successful treatment with MAOIs
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The brain's neurotransmitters serotonin, norepinephrine and dopamine are all monoamines,
meaning they have a single amino acid group, used neurotransmitters are destroyed by an
enzyme called monoamine oxidase (MAO MAOIs work by blocking the activity of this
enzyme, resulting in higher levels of neurotransmitters in the brain . MAO inactivates
tyramine and other biogenic amines in the liver and intestine by conversion of these amines
into aldehydes and there further reduction or oxidation to alcohols or carboxylic acids. They
also inactivate biogenic amines that can be found in some medications.
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There are two type of MAO in body:
MAO-A inhibition reduces the breakdown of primarily serotonin, norepinephrine; selective
inhibition of MAO-A allows for tyramine to be metabolised via MAO-B
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MAO-B inhibition reduces the breakdown mainly of dopamine and phenethylamine so there
are no dietary restrictions associated with this:Hydrazines and aralalkylamine compounds are
considered of therapeutic utility as MAO inhibitors.
Compounds: First generation:
The early MAOIs inhibited monoamine oxidase irreversibly. When they react with
monoamine oxidase, they permanently deactivate it, and the enzyme cannot function until it
has been replaced by the body
For the MAO receptors non-selective.
include drugs such as:
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Nialamide(Niamid)
Phenelzine(nardil)
are characterised by the risk of inducing a hypertensive crisis when dietary tyramine is
ingested.
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: Isocarboxazide a prodrug that is transformed from the acyl form to the hydrazine
one .
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Tranylcypromine: has CNS stimulant effect due to similarty with amphetamine,this
contributes to its overall antidepressant activity in addition to its
anti-MAOactivity.the trans isomer is the active one.
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Second generation :
Also irreversibly.preferential
Include drugs Such as:
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Chlorgyline: irreversible inhibitor MAO-A
Deprenyl selegiline (Eldepryl) irreversible inhibitor MAO-B
Third generation :
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Reversible , preferential
Bromfaromine:reversible inhibitor MAO-A
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Meclobemide: reversible inhibitor MAO-A
Toloxatone: reversible inhibitor MAO-A
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Lazabemide(RO-19-6327 ) reversible inhibitor MAO-A
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Common Side effects of monoamine oxidase inhibitors:
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Daytime sleepiness, Dizziness or lightheadedness, Low blood pressure, Diarrhea,
Nervousness, Altered sense of taste, Muscle aches, Insomnia, Weight gain
Conclusion:
MAOIs are used only when all other medications have been ruled out as effective treatments
for depression. If your physician feels you may benefit from MAOIs it is imperative that you
research possible drug interactions as well as foods to avoid any dangerous side effects. Must
known a comprehensive list of all possible drug interactions and foods is contain high levels
of tyramine that should be avoided while taking MAOIs
antidepressant medications should be used only in extreme cases of depression and as a last
resort. Even for those taking medication, lifestyle changes should also be sought in order to
treat the actual cause of the depression rather than just the symptoms.