Psychiatry

Question 1

Serotonin Syndrome presentation

Answer 1

Rapid onset and progression

• mental status change (confusion, agitation, coma)
• neuromuscular findings: ocular clonus, myoclonus, tremor, rigidity, hyperreflexia (lower>upper), planters upgoing, clonus, ataxia
• autonomic instability : htn, hyperthermia, diaphoresis, mydriasis, tachycardia

Question 2

Serotonin syndrome investigations vs neuroleptic malignant syndrome

Answer 2

Similar to NMS:
CK (usually >1000, degree of elevation correlates to severity and prognosis) 
Urine myoglobin
Leukocytosis 
Metabolic acidosis 
AST, ALP LDH elevation 
NMS: hypoCa, hypoMg, hypo or hyperNa

Question 3

Serotonin syndrome treatment

Answer 3

DC serotonin agents
Hydration (risk of rhabdo–> would alkalinize urine with NaHco3 to target pH > 6.5)
Cyproheptadine: serotonin receptor antagonist 0.25 mg/kg divided q6H
Benzo for seizure muscle rigidity or agitation
Hyperthermia: if >41 paralyze and intubate, NO SUCC (may have hyperkalemia from renal failure). Tylenol won’t work because temp isn’t from central
Resolve 24-36 hours

Question 4

Neuroleptic malignant syndrome presentation

Answer 4

Tremor
Bradykinesia

Fever + sweating
Encephalopathy (delirium, agitation, coma)
Vitals: autonomic instability 
Elevated CK and WBC
Rigidity "lead pipe"

Question 5

Neuroleptic malignant syndrome treatment

Answer 5

Stop neuroleptic 
Cooling blanket 
Dantrolene sodium (muscle relaxant)
Brim rioting (dopamine agonist)
Hydration
Monitor for arrhythmia 
Lower BP if high

Question 6

Differences between Serotonin syndrome and neuroleptic malignant syndrome

Answer 6

NMS with neuroleptics, SS with serotonin agents
NMS slow onset (days to weeks) and slow progression over 24-72 hours, SE rapid onset and progression
NMS resolved over days, SS

Question 7

Atomoxetine action and side effects

Answer 7

Selective inhibitor of pre synaptic NE transporters, increases NE and dopamine in the prefrontal cortex.

Half life: 4 hours

Side effects: HA, abdo pain, insomnia, somnolence, erectile dysfunction, irritability, fatigue, weight loss, dizziness
Serious reactions: psychosis, mania, aggression, SI, depression, sz and hepatotoxicity

Question 8

Clonidine/guanfacine

Answer 8

Pre synaptic adrenergic agonist (alpha) that stimulate inhibitory auto receptors in the CNS.

Side effects: sedation, dry mouth, hypotension, fatigue, depression, confusion

Wean off to avoid rebound hypertension

Question 9

TCAs

Answer 9

Clomipramine = primarily serotonergic 
Imipramine = serotonergic + noradrenergic 

Side effects: anticholinergic symptoms! Dry mouth, blurred vision, constipation

Question 10

SSRIs

Answer 10

Large margin of safety, no CV effects

Side effects: irritability, insomnia, appetite changes, GI symptoms, Ha, diaphoresis, restlessness, behavioural activation, sexual dysfunction