pharmacology of antidepressant

1. Pharmacology of
Antidepressant (Fluoxetine).
Presented By-
MD. Jakir Hossain
ID No. :999-17-05
Department of Pharmacy
Southern University Bangladesh

2. Content
• Depression & antidepressant.
• Fluoxetine- A SSRI.
• Pharmacology of Fluoxetine
1.Mechanism of action
2. Pharmacokinetics
3.Pharmacodynamics
4.Therapeutic uses
5.Side effect
6.Toxic effect
7.Drug interaction
8.Contraindication
9.Dose & administration
10.Precaution
11.Market preparation.

3. What is depression and antidepressant?
• Depression: Common mental disorder that presents with depressed mood,
loss of interest or pleasure, feelings of guilt or low self-worth, disturbed sleep
or appetite, low energy, and poor concentration (WHO def.)
• Antidepressant: Drugs which are used to relieve or prevent depression
known as Antidepressant.
Anti-depressant was first developed in1950’s. Act by stabilize and normalize the
level of neurotransmitter in brain. Neurotransmitter like Norepinephrine (NE),
Serotonin (5-HT), and Dopamine (DA) play an important role in regulating the
mood.

4. Selective Serotonin Reuptake Inhibitor(SSRI)
- Fluoxetine
Prototype drug.
MW: 309.33gm.
Introduced in the year 1987.
Currently the most
prescribed antidepressant.
More safer than TCAs &
MAOIs.
Fluoxetine

5. Mechanism of action
• Fluoxetine is a selective serotonin-
reuptake inhibitor (SSRI), it blocks the
reuptake of serotonin at the serotonin
reuptake pump of the neuronal
membrane, enhancing the actions of
serotonin on 5HT1A auto receptors.
SSRIs bind with significantly less
affinity to histamine, acetylcholine, and
norepinephrine receptors than tricyclic
antidepressant drugs.

6. Pharmacokinetics
Absorption
Distribution
Metabolism
Excretion
Well absorbed from the GI tract following oral administration. Oral
bioavailability is estimated to be at least 60-80%.
Peak plasma concentrations occur within 6-8 hours. 94.5% bound to
human serum proteins, including albumin and alpha-1-glycoprotein.
Fluoxetine appears to be extensively metabolized, likely in the liver,
to norfluoxetine (active metabolites) and other metabolites.
The primary route of elimination appears to be hepatic metabolism to
inactive metabolites excreted by the kidney.

7. Pharmacodynamics
• According to the amines hypothesis, a functional decrease in the activity of
amines, such as serotonin and norepinephrine, would result in depression; a
functional increase of the activity of these amines would result in mood
elevation.
• Fluoxetine's effects are thought to be associated with the inhibition of 5HT
receptor, which leads to an increase of serotonin level. Fluoxetine binds to
these and other membrane receptors from brain tissue much less potently in
vitro than do the tricyclic drugs.

8. Therapeutic uses
Mood disorder
• Major depression
disorder.
• Bipolar depression.
Anxiety disorder
• Panic disorder.
• OCD.
Others
• Bulimia nervosa.
• Premenstrual
dysphoric disorder.
• Post-traumatic
stress.

9. Side effect
• Dry mouth, abnormal vision, decreased libido, abnormal ejaculation, rash,
and sweating. Vasodilation.
• Nervous system effects such as anxiety, nervousness, insomnia, drowsiness,
fatigue or asthenia, tremor, and dizziness or light-headedness.
• GI effects such as anorexia, nausea, and diarrhoea.

10. Toxicity
• Symptoms of overdose include agitation, restlessness, hypomania, and other
signs of CNS excitation. LD50=284mg/kg (orally in mice).
• Withdrawal symptoms include flu-like symptoms, insomnia, nausea,
imbalance, sensory changes and hyperactivity.

11. Contra-indication
• Severe renal or hepatic failure.
• Hypersensitivity to fluoxetine.
• Lactation.

12. Drug interaction
• Warfarin and digoxin resulting in
adverse effects.
• Half-life of diazepam may prolong.
• Serious reactions when combine with
MAOIs.

13. Precaution
• avoid lactation because of excreted with
milk in baby.
• Close monitoring of clinical worsening
and behavioural change during first few
month of treatment.
• Keep reach out of children.

14. Dose & administration
• A dose of 20mg per day is recommended for adults and elderly in the
treatment of depression.
• A dose of 10mg which may increasing up to 60mg per day is recommended in
treatment of Bulimia nervosa and OCD.

15. Market preparation
Trade name Pack size & price Manufacturer name
Depil 20mg (cap) 100s pack 288 Tk. Opsonin pharma ltd.
Flueoxetine 20mg (cap) 50s pack 140 Tk Albion labrotories ltd.
Modipran 20mg (cap) 100s pack 289 Tk. Beximco pharma ltd.
Prolet 20mg (cap) 50s pack 150 Tk Square pharma ltd.
Prozac 20 20mg (tab) 7s pack Eli Lilly & com. USA

16. Thank You