Selective serotonin re-uptake inhibitors (SSRI's)

Question 1

Examples of SSRI’s?

Answer 1

Fluoxetine, citalopram/escitalopram, serteraline.

Question 2

Main indication for SSRI’s?

Answer 2

Depressive illness

Question 3

Mechanism of action?

Answer 3

Selectively inhibit re-uptake of serotonin from synaptic cleft so more serotonin is available.

Question 4

Escitalopram is probably the best all round SSRI. True/false?

Answer 4

True

Question 5

What SSRI has the longest half-life and is the only SSRI that is licensed for under 18 use?

Answer 5

Fluoxetine

Question 6

What does mirtazapine promote?

Answer 6

Sleep and appetite/weight gain. It is less likely to cause nausea and sexual side-effects.

Question 7

SSRI cautions and contrindications?

Answer 7

• If patient enters manic phase
• Prescribe PPI if patient also taking NSAID.
• Mirtazapine recommended if patient on warfarin.
• Do NOT prescribe any “triptans”. Triptans interact directly with some serotonin receptors in the brain hence also increasing probability of serotonin syndrome.

Question 8

Adverse effects of SSRI?

Answer 8

GI - nausea, vomiting, dyspepsia (impaired digestion).

CNS - dizziness, insomnia, headache.

Spinal - sexual dysfunction

Can cause transient increase in self-harms/suicidal ideas, especially in those younger than 25 years.

Question 9

Why shouldn’t monoamine oxidase inhibitors be given with SSRI’s?

Answer 9

Potential risk of causing serotonin syndrome.

Question 10

What is serotonin syndrome?

Answer 10

Potentially life threatening drug induced condition caused by too much serotonin in the brain synapses.

Question 11

symptoms of serotonin syndrome?

Answer 11

Agitation or restlessness.
Insomnia.
Confusion.
Rapid heart rate and high blood pressure.
Dilated pupils.

Question 12

What is difference between SSRI and SNRI?

Answer 12

SSRI = selective serotonin reuptake inhibitor

SNRI = serotonin and noradrenaline reuptake inhibitor

Question 13

Example of an SNRI and it’s use?

Answer 13

Duloxetine

Licensed use for depression and anxiety disorders along with stress incontinence and diabetic neuropathy.

Question 14

What types of drugs are “triptans”?

Answer 14

Selective serotonin agonists

Question 15

Why are SSRI’s not given alongside triptans?

Answer 15

Triptans interact directly with some serotonin receptors.

If given with an SSRI/SNRI, it could cause too much serotonin to be present in the brain leading to potential serotonin syndrome.

Question 16

What is a potential side-effect of SSRI’s that patients should be counselled about?

Answer 16

Sexual dysfunction

Question 17

What is the triad of symptoms for serotonin syndrome?

Answer 17

Mental state changes

Autonomic hyperactivity (diarrhoea and pupil dilation)

Tremor