Anti depressant agents

2. What is depression………….?
An illness that involves the body, mood, and thoughts, that affects
the way a person eats and sleeps, the way one feels about
oneself, and the way one thinks about things.
DEPRESSION may be described as feeling sad, blue (fed up),
unhappy, miserable, or down in the dumps. Most of us feel this
way at one time or another for short periods. True clinical
depression is a mood disorder (affective disorder) in which
feelings of sadness, loss, anger, or frustration interfere with
everyday life for weeks or longer.
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3. Common Sign of Depression
• Sad , anxious or ‘empty’ mood
• Feeling of hopelessness
• Feeling of guilt, helplessness
• Difficulty in concentrating, remembering, making decisions.
• Oversleeping
• Appetite and/or weight changes
• Thoughts of death, suicide or suicide attempts
• Restlessness, irritability
• Loss of interest or pleasure in hobbies and activities that
were once enjoyed, including sex.
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4. Depression in Men
• According to the statistics, men are less likely to suffer
from depression than women.
• Depression typically shows up in men, not as feelings of
helplessness and vulnerability, but as being irritable, angry
and uncooperative. Depression may therefore be difficult
to recognize as such in men.
• Even if a man realizes that he is depressed, he is perhaps
less willing than a woman to seek help. Encouragement
and support from a partner and/or family members can
make a big difference here.
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5. Depression in Women
• Women are about twice as likely as men to experience
depression. A number of factors may explain this.
• Hormonal factors
• Changes in menstrual cycle
• Pregnancy
• Miscarriage
• The time immediately after the birth of a baby
• Pre-menopause and menopause are all associated with
hormonal changes.
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6. Causes of depression
• The exact cause of depression is not known. Many
researchers believe it is caused by chemical changes
in the brain. This may be due to a problem with
your genes, or triggered by certain stressful events.
More likely, it's a combination of both.
• Some types of depression run in families. But
depression can also occur if you have no family
history of the illness. Anyone can develop
depression, even kids.

7. The following may play a role in depression:
• Alcohol or drug abuse
• Certain medical conditions, including underactive thyroid, cancer, or
long-term pain
• Certain medications such as steroids
• Sleeping problems
• Stressful life events, such as:
– Breaking up with a boyfriend or girlfriend
– Failing a class
– Death or illness of someone close to you
– Divorce
– Childhood abuse or neglect
– Job loss
– Social isolation (common in the elderly)

8. TREATMENT FOR DEPRESSION
• Psychotherapy
• Electroconvulsive therapy (ECT)
• Natural alternatives (natural and herbal remedies)
• Medication
• SSRIs (Selective-Serotonin Reuptake Inhibitors)
• MAOIs (Monoamine Oxidase Inhibitors)
• TCAs (Tricyclic Antidepressants)
• SNRIs (Selective Nor-epinephrine Reuptake Inhibitors)
• NDRIs (Nor-epinephrine Dopamine Reuptake Inhibitors)
• Psychotherapy/talk therapy – especially useful when combined with medications.
Goal is to teach good coping skills for every day stressors
• ECT – electric shock is applied to scalp through electrodes, results in seizure
(convulsion) in the brain. Fast and effective in patients with depression or suicidal
thoughts. Usually given up to three times a week for two to four weeks.
• Natural alternatives – sold in teas and tablets, and in diet pills-not good for severe
depression but can help mild depression (omega-3 fatty acids, folic acid, diets,
exercise etc.)

9. Bipolar Disorder
• Bipolar disorder is a mood disorder that causes radical
emotional changes and mood swings, from manic highs to
depressive lows.
Depression and mania are considered to be the polar
opposites of human emotion. The term "bipolar" describes
the swings between these two emotional "poles."
• During a "manic phase," people with bipolar disorder
experience feelings of euphoria (elation), happiness, and
hyperactivity. During a "depressed phase," feelings of
sadness and depression are the normal.
• When the person experiences a depressive episode only, then
it is called a unipolar disorder. When the episode occurs
between the two poles of depression and mania (obsession,
craze), it is called bipolar disorder.
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10. There are two subtypes of bipolar disorder:
1.Bipolar disorder type I: episode of mania with or without
depression.
2.Bipolar disorder type II : episode of depression with episode of
hypomania or mania.
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Depression can appear as anger and discouragement, rather than
feelings of sadness. If depression is very severe, there may also
be psychotic symptoms, such as hallucination (nightmare, imagined
thing).

11. Causes of bipolar disorder
1.Genetic: bipolar disorder is higher (7 times more) among the
people whose parents have this disorder.
2. Biochemical: a number of neurotransmitters have been
responsible for this disorder. Drugs like cocaine exacerbate
mania and tricyclic antidepressant triggers mania.
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12. • Antidepressant drugs are medicines that relieve symptoms
of depressive disorders.
• Depressive disorders may be unipolar or bipolar.
• These agents act by increasing the levels of excitatory
neurotransmitters. The main types of antidepressants are:
1. Tricyclic antidepressants- amitriptyline ,imipramine,
nortriptyline
2. Monoamine oxidase inhibitors (MAOIs)-phenelzine
,tranylcypromine.
3. Selective Serotonin reuptake inhibitors (SSRIs)-fluoxetine,
paroxetine, and sertraline.
4. Tetracyclic compounds and atypical antidepressants which
do not fall into any of the above categories.

14. Classification
• Divided into 3 groups:
 1st generation: Block the
oxidative deamination of
various biogenic
monoamines-Iproniazid
 2nd generation: Act
selectively-cimoxatone
 3rd
generation: act
reversibly & selectively-
Metralindole
Iproniazid
Metralindole

15. Structural references:
 Aryl moiety(X)
 Alkyl moiety(Y)
 Hydrazine part
1.Variation of aryl
moiety:
I. If phenyl ring is mono-
substituted with polar
group will increase
anti-depressant
activity.
II.If benzene ring is
replaced by other
heterocyclic ring
reduces activity.
X Y-NH-NH2

16. 2.Variation of alkyl moiety:
I. If X=CH2,comp is benzyl hydrazine.
II. If X=CH2-CH2, comp is phenethyl
hydrazine or Phenelzine which is
active.
III. If X=CH2CH2CH2,comp is
3-phenylpropyl hydrazine which is
less potent than Iproniazid.
I. If Y=branching (CH2-CH-CH3), comp is
Pheniprazine(most potent MAOI)
II. If Y=further branching, causes loss of
activity.
3.Variation of Hydrazine part:
I. H2 atom on hydrazine nitrogen
bearing alkyl group is essential for
MAOI activity.
X Y-NH-NH2

17. • Depression linked to an imbalance of chemicals within
the brain.
• In brain there are chemical
messengersneurotransmitters, called monoamines-
noradrenalin , serotonin.
• Neurotransmitters control or regulate bodily functions,
& noradrenalin and serotonin control and regulate
mood.
• During depression, there may be a decrease in amount
of these monoamines released from nerve cells in the
brain. Monoamines are broken down by an enzyme
called monoamine oxidase.
• MAOIs prevent monoamine oxidase from breaking
down the monoamines. This results in an increased
amount of active monoamines in the brain.
• By increasing the amount, the imbalance of chemicals,
important in causing depression, is altered. This helps
relieve the symptoms of depression.
• Moclobemide is a more selective type of MAOI, called
a reversible inhibitor of monoamine oxidase type A
(RIMA).

19.  Many drugs should be avoided when taking an
MAOI antidepressant. The most common are:
• Allergy, cold, cough and sinus medications
• Antihistamines
• Antipsychotics
• Asthma drugs
• Blood pressure medications
 Other antidepressants not specifically listed,
including other MAOIs
• Tryptophan
 Often interact with certain foods; e.g. Alcoholic
beverages, fermented foods, soya sauce.

20. • A class of compounds typically
used as antidepressants in the
treatment of:
– depression,
– anxiety disorders,
– personality disorders.
• Typically effective and used in
treating some cases of insomnia.

21. • 1967-Research for alternative drugs to help
depressed patients began.
• At the time, most scientists believed that
norepinephrine was the chemical messenger that was
really involved in the depression.
• However, interest began to develop in serotonin as
well.
• Due to that increasing interest, as well as interest in
finding antidepressants that would have more
tolerable side effects, the serotonin-specific
reuptake inhibitors, or SSRIs, came about.
• The first drug in this class was fluoxetine (Prozac).
• Researchers suggest that these drugs work by only
blocking the reuptake of serotonin, thereby reducing
side effects.

22. 1. SSRI antidepressants are believed
to involve a chemical in the brain
called serotonin. Serotonin is one of
the "neurotransmitter" chemicals
important in communication between
nerve cells.
2. SSRIs reduce the amount of
serotonin that is reabsorbed by the
presynaptic neuron. As a result,
more of this neurotransmitter
remains in the synaptic gap for a
longer time, which gives
Pharmacological effect of some
depressed people.
3. SSRIs are different from tricyclics,
because they block only the
reuptake pumps for serotonin, and
not those for norepinephrine.
.

23. Beginning with the combination of SSRIs with
other antidepressants, the following can occur:
I.Combining SSRIs with tricyclic and tetracyclic
antidepressants can result in abnormal heart
rhythms.
II.Combining SSRIs with monoamine oxidase
inhibitors (MAOI's) can result in a very serious
disease called serotonin syndrome.

24. A f ew examples....
Paroxetine
Fluoxetine
Sertraline
Escitalopram
Fluvoxamine
Citalopram

26. Tricyclic Antidepressants
(TCAs)
Monoamine Oxidase
Inhibitors (MAOIs)
Selective Serotonin
Reuptake Inhibitors (SSRIs)
TCAs work mainly by increasing
the level of norepinephrine in the
brain synapses, although they also
may affect serotonin levels.
MAOIs elevate the levels of
neuro-chemicals in the brain
synapses by inhibiting
monoamine oxidase.
Selective serotonin reuptake
inhibitors (SSRIs) are medications
that increase the amount of
serotonin neuro-chemical in the
brain.
TCAs impair the ability to break
down tyramine which cause
dangerously high blood pressure
MAOIs impair the ability to break
down tyramine which cause
dangerously high blood pressure
SSRIs do not interact with
tyranine in food
TCAs produce severe side effects
MAOIs produce severe side
effects
SSRIs are generally well tolerated
and side effects are usually mild
TCAs have more
anticholinergic and
cardiovascular side effects
MAOIs have more
anticholinergic and
cardiovascular side effects
SSRIs have fewer
anticholinergic and
cardiovascular side effects
TCAs have fewer sexual and
gastrointestinal side effects
MAOIs have fewer sexual
and gastrointestinal side
effects
SSRIs have severe sexual and
gastrointestinal side effects
TCAs are more toxic than SSRIs
but less toxic than MAOIs.
MAOIs are the most toxic among
the three.
SSRIs are the least toxic among
the three.