Anti-Depressants

Question 1

MAOI

Answer 1

Phenelzine,Selegiline,Tranylcypromine

MAOI(monoamine oxidase inhibitor) Inhibiting breakdown of NA, serotonin and dopamine

Side effects: weakness, headache, weight gain, dizziness, fatigue, impotence

Interactions: Not to be used in combinition with SSRI, Tricyclic or some analgesics as increasing serotonin levels to potentially dangerous - confusion, hyertension/neuroleptic malignant syndrome, coma and possible death

Food high in tyramine (cheese, alcohol) - hypertensive crisis 14 days of washout period

Question 2

RIMA

Answer 2

Moclobeminde

RIMA (reversible inhibition of MAO type A)

short acting,

7days of washout period

Question 3

Tricyclic

Answer 3

1. Amitryptyline, Nortriptyline
2. Clomipramine, Imipramime, Lofepramine
3. Trazodone: more sedating

inhibiting reuptake of serotonin and NA via blocking the transporters responsible, hence increasing concentrations within synapses

Used in depression, anxiety, chronic pain (fibromyalgia, reflex sympathetic dystrophy syndrome -RSD), IBS, neuralgia, OCD, Noturnal enuresis - bed wetting, PTSD

Side effects:

• Cardiac arrythmias,
• Antimuscarinic effect - reduce GI motility - constipation, dry eyes and mouth, reduce bronchial secretions,
• Urinary retention
• Dangerous in overdose, high risk of suicide

Question 4

SSRI

Answer 4

Most widely prescribed antidepressants

1. Fluoxetine (used in pregnancy, breastfeeding woman), Paraxetine
2. Sertraline
3. Citalopram, Escitalopram

inhibit reabsorption of serotonin, weak affinity for NA and Dopamine

Used in depression, anxiety, OCD, panic attacks, PTSD, eating disorders

Side effects:

• Sexual dysfunction and reduced libido
• Cardiac: Long QT(Citalopram)
• Bleeding: affect anticoagulants (warfarin and asprin), risk of GI bleeding
• Suicide: generally not prescribed to under 18s
• Epilepsy: reduced fit threshold
• Others: nausea, rash, muscle aches, insomnia - taken in the morning, sweating

Question 5

Duloxetine

Answer 5

SNRI (serotonin NA reuptake inhibitor)

used in depression-3rd line, neuropathic pain (diabetes, fibromyalgia), stress urinary incontinence

Side effects: nausea, insomnia, dizziness

Question 6

Mirtazapine

Answer 6

SNRI

Also presynaptic alpha2 adrenoreceptor antagonist;

Used in depression, anxiety, PTSD

Side effects: Low dose(15mg) cause drowsiness but higher dose as stimulant/insomnia

Question 7

Venlafaxine

Answer 7

SNRI

Used in major depressive disorder (resistent depression not responding to SSRI or TCAs), anxiety, panic disorder, social phobia, metabolised into desvenlafaxine by cytochrome P206 in the liver