Medication in Old Age Psychiatry Flashcards
What are the concerns in Old Age Psych?
Absorption: reduced gut motility slower action
Distribution: volume increased longer duration of action, higher site [ ], less albumin so more “free” drug
Metabolism: affected by hepatic disease and blood flow
Excretion: eGFR 35% less by 65, 50% less by 80
What are the principles of prescribing in old age psych?
Start low, titrate up
May take longer to respond to treatments
Regular reviews considering co-morbidities and other meds
Simple regimes
Consider swallowing difficulties
What are the SE/problems with opiates?
agitation
dizziness
What are the SE/problems with antipsychotics?
agitation
sedation
What are the SE/problems with ACh inhibitors?
oxybutynin, amitriptyline
confusion, worsening cognitive function, GI disturbance, blurred vision, glaucoma, urinary retention
What are the SE/problems with SSRIs?
GI disturbances, GI bleeds
What are the SE/problems with Digoxin?
confusion, hallucinations
Describe steroid induced psychosis?
High doses may lead to hypomania, mania, psychosis
More common in women, can either taper the steroid dose or add anti-psychotics
What drugs have the highest risk of anticholinergic SEs?
TCAs, clozapine, haloperidol, trifluoperazine
What drugs have the medium/low risk of anticholinergic SEs?
mirtazapine, paroxetine, risperidone, zuclopenthixol, chlorpromazine
When are anticholinesterases used? What are their SEs?
Used in dementia
GI upset, muscle cramps, sleep disturbances, syncope
• ~50-60% effective
What is memantine?
Dementia treatment
Glutamate receptor antagonist
Start at 5mg. Max = 20mg
SEs of memantine?
Nausea, restless, headache, stomach ache
What are the SEs of TCAs?
High risk – postural hypotension, cardiac abnormalities, anticholinergic effects i.e. delirium, urinary retention, dry mouth, constipation
What are the problems associated with lithium?
Narrow therapeutic window
Avoid in cardiovascular disease and severe renal impairment
Caution in thyroid problems
