Antidepressants

Question 1

what is the suspected cause of depression

Answer 1

low levels of serotonin however is still unclear but more likely the reduction in serotonin receptors in the hippocampus

this is why SSRI s take so long to take effect

Question 2

Mono amine oxadase inhibitors MAOI

Answer 2

• These inhibit the activity of MAO enzymes
• MAO enzymes break down norepinephrine/serotonin and dopamine, so this drug prevents this

NAMES OF DRUG:

• phenelzine
• selegiline (also used in Parkinson’s)
• Tranylcypromine

Side effects:

• weakness
• dizziness
• headache
• fatigue
• weight gain
• impotence

Question 3

what do MAOI interact with

Answer 3

should NEVER be prescribed in combination with SSRI/Tricyclic as well as analgesics such as morphine/tramadol as they will increase serotonin to potentially dangerous levels causing confusion, hypertension, tremor, coma and even death

MUST BE GIVEN A 14 DAY COOL OFF PERIOD BEFORE STARTING ON ANOTHER ANTI-DEPRESSANT

Question 4

MAOI and foods high in tyramine

Answer 4

cheese
meats such as venison
alcohol
some green vegetables such as green beans

Question 5

reversible MAOI

Answer 5

moclobeminde

• reversible inhibition of MAO type A therefore is known as RIMA
• tyramine has less of an effect on frugs like this
• has a short acting period so medications can be changes with only a week wash out period

Question 6

Tricyclic Antidepressants

Answer 6

act by inhibiting the re-uptake of norepinephrine and serotonin by blocking the transporters responsible fro re-uptake of these neurotransmitters

thus increasing the concentration of neurotransmitters in the synapses and triggering further neurotransmission

Question 7

what are the uses of tricyclic antidepressants

Answer 7

depression 
anxiety 
chronic pain 
IBS 
neuralgia 
OCD 
nocturnal enuresis 
PTSD

Question 8

tricyclic antidepressants cautions

Answer 8

CVD due to the risk of arrhythmias

have antimuscarininc activity that blocks activity of the the muscarinic acetylcholine receptor and so reduce intestinal mobility

They can induce bradycardia followed by tachycardia, reduce bronchial secretions, urinary retention, dry mouth and confusion

tricyclics are very dangerous in overdose so beware of how much you prescribe for a patient and use with caution in patients at high risk of suicide.

Question 9

tricyclic antidepressants examples

Answer 9

Amitriptyline
Clomipramine
Imipramine
Lofepramine
Nortriptyline

Question 10

Trazodone:

Answer 10

this drug is more sedating

Question 11

SSRI

Answer 11

Believed to work by increasing levels of neurotransmitter serotonin by limiting its re-absorption and pure SSRI have only a weak affinity for norepinephrine and dopamine transmitters

Question 12

Serotonin receptors are known as

Answer 12

5-hydroxytryptamine (5-HT)

they are cleaner with generally fewer side effects and tend to be better tolerated by patients

Question 13

uses of SSRI’s

Answer 13

Depression
Anxiety
OCD
Panic disorder
PTSD
Eating disorders

Question 14

where are serotonin receptors found

Answer 14

are found in the peripheral and central nervous systems mediating both excitatory and inhibitory neurotransmission

Question 15

what do serotonin receptors modulate the release of

Answer 15

GABA
Dopamine
Epinephrine
Norepinephrine
Acetylcholine

therefore they influence aggressions anxiety, cognition, learning memory, mood and sleep

Question 16

SSRI side effects

Answer 16

Sexual: dysfunction and reduced libido
Cardiac: some, especially citalopram, to be used with caution as can cause QT interval prolongation therefore dose dependant with citalopram
Bleeding: affects anticoagulants (i.e. warfarin and aspirin) and also increased risk of GI bleeds

Suicide: possible increased risk of suicide especially in children and adolescents
May only be prescribed in under-18s by a psychiatrist
Overdose: safer than other antidepressants
Epilepsy: may reduce fit threshold
Others include:
Nausea
Rash
Muscle aches
Insomnia
Sweating

Question 17

the order of the level of toxicity in SSRI Toxicity

Answer 17

citalopram 
escitalopram 
Paroxetine 
Sertraline 
Fluoxetine

Question 18

Duloxetine: SNRI (serotonin norepinephrine up-take inhibitor)
uses and side effects

Answer 18

Uses:
Depression
Neuropathic pain (diabetes, fibromyalgia)
Stress urinary incontinence

Side effects:

• nausea
• insomnia
• dizziness

Question 19

Mirtazapine:

Answer 19

a presynaptic alpha₂-adrenoreceptor antagonist. Also a noradrenergic and specific serotonergic antidepressant NaSSA

uses:
Depression
Anxiety
PTSD

side effects:
Low dose causes drowsiness so best taken at night
Higher dose more stimulant effect

Question 20

Venlafaxine:

Answer 20

serotonin-norepinephrine re-uptake inhibitor (SNRI)

uses:
Major Depressive Disorder
Anxiety
Panic
Social phobia
Metabolized in the body into desvenlafaxine (by cytochrome P206 isoenzyme in the liver)
Often used in treatment of resistant depression

Question 21

lithium In bipolar/mania modd stabilisation

Answer 21

possible adverse affects on kidney and thyroid function.

Question 22

Tricyclics for pain management

Answer 22

work by blocking the re-uptake of Noradrenaline and Serotonin (5-HT) into the nerve endings and increasing their levels in the pain control pathways

Their benefit arises: by their direct effect on pain, and also through beneficial effects on sleep

Question 23

Prolongation of the QT interval can lead to a life threatening arrhythmia known as

Answer 23

torsades de pointes

CITALOPRAM

Question 24

People who have more risk factors for QTc prolongation

Answer 24

• Major psychiatric disorders.
  
  • Cardiovascular disease.
  • The elderly.
  • Women.