Anti-Depressants | SSRI's

Question 1

What are the medications that are found in this class?

Answer 1

1. Fluoxetine
2. Fluvoxamine
3. Paroxetine
4. Citalopram
5. Escitalopram
6. Sertraline

Question 2

What is their mechanism of action?

Answer 2

They work by inhibiting the serotonin-reuptake-transporters which increases the amount of serotonin in the synaptic cleft overcoming the shortage caused by major depressive disorder for example. It should be noted that it takes a while for serotonin to accumulate in the synaptic cleft therefore it takes 4 to 6 weeks to achieve clinical effects

Question 3

What are their indications?

Answer 3

1. Major Depressive Disorder (first line medication)
2. Chronic Anxiety Disorder
3. Obsessive Compulsive Disorder (OCD)
4. Eating Disorders
5. PTSD

Question 4

What are their side effects?

Answer 4

General:
1. Anxiety
2. Insomnia
3. GI Disturbances (e.g. diarrhea)
4. Sexual Dysfunction
5. Suicidal Ideation (Esp. patients below 25)
6. Serotonin Syndrome
7. Withdrawal Symptoms: headaches, insomnia and irritability.

Drug Specific:
1. Fluoxetine, fluvoxamine and paroxetine inhibit the liver enzyme P450.
2. Paroxetine can cause congenital malformations when given during pregnancy (Class D)

Question 5

What is serotonin syndrome? And how is it treated?

Answer 5

Serotonin syndrome occurs when SSRI’s are given in combination with other serotonin increasing medications which leads to over-accumulation of serotonin which hyperactives the nervous system.

Sx:
1. Flushing
2. Hyperthermia
3. Agitations
4. Muscle Rigidity
5. Convulsions
6. Coma

Tx:
Cyproheptadine