Antidepressants Flashcards
what are the main classes of antidepressants?
- SNRI’s
- SSRI’s
- others: MAOI, Trazodone, bupropion
what are the two types of SNRI’s
TCA and venlafaxine
what receptors does the TCA block?
blockage of M, alpha-1, and H1 receptors
what are the common M-block adverse effects?
- Dry mouth
- Constipation
- Urinary retention
- Mydriasis
- Blurred vision
- Confusion
what are the common alpha-1 block adverse effects?
- Orthostatic hypotension
- Sedation
- Sexual dysfunction
what are the common H-1 block adverse effects?
- weight gain
- sedation/drowsiness
what are some other adverse effects of TCA that is not from the receptor blockage
- sexual dysfunction - serotonin acting at 5-HT2a receptors
- weight gain
overdosing on TCA can lead to what?
life-threatening cardiac arrhythmias
what type of drug is venlafaxine
SNRI
how does venlafaxine differ from TCA?
- weakly inhibits dopamine reuptake
- no significant alpha1, H1 or M-block - so less adverse effects
what is the most commonly prescribed antidepressant class?
SSRI
which has more severe adverse effects? TCA or SSRI?
TCA, SSRI receptor blocks less potent than with TCA
what is serotonin syndrome
occurs in response to increased serotonin levels
- can also be caused by “high-normal” dose in a sensitive individual
what are the triad of symptoms of the serotonin syndrome
§ Altered mental status
§ Autonomic hyperactivity
§ Neuromuscular abnormalities
when a patient has autonomic hyperactivity, what does it look like
patient is often hot and sweating with a fast heart rate and high blood pressure that goes up and down
when a patient has neuromuscular abnormalities from serotonin syndrome, what does it look like?
hyperreflexia and clonus are particularly common and are more often pronounced in the lower extremities
how to treat serotonin syndrome?
○ Remove the causative agent
§ Most cases typically resolve 24 hrs after
○ Interfere with serotonin action
§ Cyproheptadine can be given – serotonin antagonist
○ Symptomatic treatment
§ Treat the agitation with benzodiazepines (BDZ)
how does MAOI’s work
block monoamine oxidase, the enzyme that metabolizes NE, resulting in higher NE levels
MAOI can induce a hypertensive crisis when combined with foods containing
tyramine
Trazodone is a ?
Inhibits serotonin reuptake, but not considered an SSRI
○ Also acts directly as an antagonist at serotonin 5-HT2A receptors
trazodone has a strong sedative effect. why?
H1-block and potent alpha-1 block effects
what’s so important about brand names for bupropion
to distinguish therapeutic uses
what are the two brand names of bupropion and their therapeutic uses?
wellbutrin = antidepressant
Zyban = smoking cessation therapy
what is the mechanism of Bupropion?
relatively weak inhibition of NE and dopamine reuptake
