Antidepressants Flashcards
Monoamine Oxidase Inhibitors (names)
Isocarboxazid
Phenelzine
Tranylcypromine
Selegiline
MAOI MOA
Blocks the inhibitory effects of MAO so that there will be more 5HT, NE & DA in the synaptic cleft
MAOI site of action
Mitochondria
Hydrazine derivative MAOI
Phenelzine
Isocarboxazid
Non-hydrazine derivative MAOI
Tranylcypromine
Selegiline
Preference of MAO-A & MAO-B
MAO-A = NE & 5HT MAO-B = DA & Tyramine
MAOI AEs (9)
Drowsiness Insomnia Nausea O. Hypotension Weight gain Muscle pain Sexual dysfunction Serotonin syndrome Cheese reaction
What drugs causes Serotonin syndrome?
How does this happen?
MAOI + any Serotonergic agent
Overstimulation of 5HT1A & 5HT2 receptors
Symptoms of Serotonin Syndrome
Muscle rigidity
Hyperthermia
Myoclonus
Serotonin syndrome management
“4S”
- Serotonergic agent discontinuation
- Supportive care
- Sedation w/ Benzos
- Serotonin antagonist = Cyproheptadine
Cyproheptadine + Benzo is used for?
Serotonin syndrome management
Cause of Cheese Reaction?
Excess tyramine buildup (MAO degrade tyramine in cheese, wine, etc)
Symptoms of Cheese reaction
- Tachycardia
- Hypertension
- Arrhythmias
- Seizures
- Stroke
MAOI Contraindications “2Ps”
“2Ps”
OTC cold preparations:
- pseudoephedrine
- phenylpropanolamine
Cheese Reaction (Tyramine-induced HTN) Management
“2Ps”
- Phentolamine
- Prazosin
Tricyclic Antidepressants (names)
“Pramine” & “Triptyline”
- Amitriptyline
- Clomipramine
- Desipramine
- Imipramine
- Nortriptyline
TCAs MOA
Blocks SERT & NET (Inc. 5HT & NE in cleft)
Selectivity of TCAs for SERT & NET
SERT: Clomipramine
NET: Desipramine & Nortriptyline
TCAs Overdose Management
Sodium bicarbonate to reverse the conduction block
Why are TCAs avoided in elderly?
Can cause:
- Orthostatic hypotension
- Reflex tachycardia
Selective Serotonin Reuptake Inhibitors (SSRI) (names)
- Citalopram
- Escitalopram
- Fluoxetine
- Fluvoxamine
- Paroxetine
- Sertraline
DOC for treating depression
SSRI
SSRI MOA
Blocks SERT = No serotonin reuptake
SSRI AEs
Gut = nausea, GI upset & diarrhea Dec sexual function & interest Weight gain Serotonin syndrome when used w/ MAOI Overdose = Seizures
what are the best anti-depressants to start the pt. on?
Citalopram, setraline or Escitalopram
Low potential for interactions
Serotonin & Norepinephrine Reuptake Inhibitors (SNRI) (names)
- Venlafaxine
- Duloxetine
What drug should you switch the pt to if SSRIs provide no relief?
SNRIS - Venlafaxine & Duloxetine
Norepinephrine & Dopamine Reuptake Inhibitors (NDRI) (names)
- Bupropion
Overdose of Bupropion causes?
-Seizures (so contraindicated in pts. w/ seizure disorders)
Noradrenergic & Specific Serotonergic Antidepressants (NASSA) (names)
- Mirtazapine
NASSA (Mirtazapine) MOA
- Central presynaptic A2 antagonist - Inc NE & 5HT release
- 5HT2 & 5HT3 Antagonist
- H1 antagonist
NASSA (Mirtazapine) AE
- Sedation & weight gain (H1)
Antidepressant Discontinuation Syndrome symptoms
- Anxiety, irritability & tearfulness
- Dizziness
- Headache
- Lethargy
- Flu-like symptoms
- Electric-shock sensations
- Insomnia
- Nausea, vomiting & diarrhea
Drugs most likely to cause Antidepressant Discontinuation Syndrome
- Paroxetine
- Venlafaxine
Due to short half life
Drug least likely to cause Antidepressant Discontinuation Syndrome
- Fluoxetine
Due to long half life
Clinical uses of SSRIs
- Depression (DOC)
- Anxiety (DOC) - GAD, SAD, PTSD, PD & OCD
- Eating disorders - Bulimia
- Premenstrual Dysphoric Disorder
Clinical uses of Bupropion
- Depression
- Smoking cessation
Clinical uses of TCAs & SNRIs
- Depression
- Chronic pain (neuropathic, etc.)
DOC for Bipolar Disorder
- Lithium
NB: AD may worsen the symptoms of Bipolar so always rule out the disorder before using AD
Lithium MOA
Inhibits Inositol polyphosphatase & monophosphatase –> No Inositol regeneration
Adverse effects of Lithium
- Tremor, ataxia & aphasia
- Sedation & seizures
- Weight gain
- Hypothyroidism
- Nephrogenic DI
- Edema
- Dermatitis
- Alopecia
- Leukocytosis
Management of Lithium-induced Nephrogenic DI
- Discontinue OR
- Add Amiloride
- Thiazides & NSAIDs
Contraindications of Lithium
- Nursing mothers
- Cat D in pregnancy - Congenital cardiac anomalies
Monitoring the bodily effects of Lithium
- Serum lithium conc.
- Thyroid function
- Renal function
Drugs that reduce the Renal clearance of lithium
- Thiazides
- NSAIDs
- ACEI
- ARBs
Alternatives to Lithium
Antiepileptics - Valproate, Carbamazepine & Lamotrigine
Atypical AP - Olanzapine, Aripiprazole, Quetiapine & Risperidone
Monitoring of Lithium-alternatives
- Valproate - Liver function & CBC
- Carbamazepine - CBC
