SSRI/SNRI
This SNRI is also FDA approved for treatment of diabetic neuropathy and chronic MSK pain.
Duloxetine (Cymbalta)
This mood stabilizer is primarily cleared by the kidneys and thus requires renal monitoring, with increased risk of toxicity with age related GFR decline.
Lithium.
Note that in older adults, even minor dehydration can cause significant increase in lithium levels.
The FDA instituted a black box warning for use of atypical antipsychotics (later extended also to typicals) for use in elderly dementia patients for increased risk of death.
Are antipsychotics still used in this population?
Yes *
What is the general mantra for prescribing to older adult patients?
Start low and go slow
Fluvoxamine - 14-16 hours
(Paxil - 21 hours)
This mood stabilizer is primarily metabolized via glucoronidation and has relatively fewer drug interactions, however, metabolism is notably inhibited by valproate and induced by carbamazepine.
Lamotrigine.
Reduced dose needed if combined with depakote.
May require higher doses with carbamazepine (or risk for elevated levels if carbamazepine stopped)
The incidence of this extra pyramidal side effect exceeds 50% after 2-3 years in older adults taking first generation antipsychotic medication.
Tardive dyskinesia.
Incidence is lower with second generation antipsychotics, however, older adults are at much higher risk than younger adults.
What alternative treatments (not medication) would you consider to treat an geri inpatient who has declining PO intake and somatic presentation of depression?
ECT!
What side effects for SSRIs might you have more concern about when treating older adults?
Hyponatremia
Apathy
Activation - worsened anxiety
bleeding risk (anti-platelet effect)
This anticonvulsant/mood stabilizer has been shown in small RCTs to have possible benefit towards agitation in dementia, though its use is limited by risk of side effects including hyponatremia and drug-drug interactions.
Carbamazepine. Has the best evidence amongst the mood stabilizers for agitation in dementia. However, it is a potent CYP inducer resulting in meaningful interactions with psychiatric and non-psychiatric meds.
What is the medication approved for treatment of psychosis in Parkinson's disease? (for extra points, what is the MOA?)
Pimavanserin (brand name Nuplazid)
MOA: selective inverse agonist of the serotonin 5-HT2A receptors
(Clinically also use seroquel and can use donepezil as well - some limited evidence base)
What is the BEERS Criteria?
a list of medications that are potentially inappropriate for older adults (65+) because they carry a higher risk of causing adverse health problems, like confusion, falls, or serious side effects, often due to age-related changes in how the body processes drugs. Developed and updated by the American Geriatrics Society (AGS)
Alternative Treatments to Selected Medications in the 2023 American Geriatrics Society Beers Criteria® (DOI: 10.1111/jgs.19500) in the Journal of the American Geriatrics Society (JAGS).
This is the maximum dose of Celexa recommended by the FDA for patients above 60 due to concerns for QTC prolongations.
20 mg daily.
What is the target therapeutic window for lithium in older adults?
General Adult:
Mania – 0.8-1.0mmol/L
Depression – 0.6-0.8mmol/L
Maintenance –0.6-0.8mmol/L
Geriatrics
Aim for 0.4 - 0.6 with 0.8 upper limit for mania
Why?
Decrease clearance via kidney and some thought that more cross over BBB
Which antipsychotic is FDA approved for agitation in dementia?
Brexipiprazole
(though in clinical practice we still use risperidone and aripiprazole given cheaper costs and evidence based for efficacy; you will see quetiapine used as well)
What class of medications is used to treat apathy in older adults with dementia/parkinson’s?
Stimulants
methylphenidate IR is preferred starting agent, e.g. 2.5 mg BID, up to 5 mg BID, then reassess monitoring appetite, irritability, insomnia)
This SSRI is typically non-preferred/used with caution in older adults due to relatively high anticholinergic effect.
Paroxetine (Paxil)
In geriatric psychiatry we have to pay attention to medication interactions, particularly with patients who may have multiple co-morbidities.
What are some notable medication interactions of valproic acid?
***CYP3A4 inhibitor (which has many substrates!!!)
Increase levels of: Lamotrigine, Quetiapine, TCAs, warfarin, methadone, trazodone ….
Decrease levels of: Olanzapine
You have a patient who has been on clozapine long term. She falls and breaks her hip and enters a SNF for rehab. She is a chronic heavy smoker.
What might you be thinking about in regard to management of her clozapine?
Clozapine is metabolized by CYP 1A2 (70%), CYP3A4, and CYP2D6
Smoking (specifically hydrocarbons in cigarettes) = CYP1A2 inducer through aryl-hydrocarbon receptor.
Clozapine levels can rise up to 50% following smoking cessation!
Can take 4 weeks - think of this w. extended hospitalizations too!
Why are dosing recommendations for geriatric patients different than general adult patients?
1 - Older adults are more likely to experience adverse effects
2 - Changes in body's ability to clear and metabolize!
↑ Heterogeneity of drug clearance and doses
↑ Body fat, ↓ lean body mass: ↑ volume of distribution for lipophilic drugs (keep this in mind for reported substance use like cannabis as well!)
↓ drug clearance of many drugs
⇨ drugs or drug metabolites can accumulate over time and lead to toxiceffects.