Mood Stabilizers and Anticonvulsants Flashcards
what are mood stabilizers most frequently used for?
treating acute mania and to help prevent relapse episodes of mania in bipolar and schizoaffective disorders
What are the “mood stabilizers?”
they include lithium, and anticonvulsants (valproic acid, lamotrigine, and carbamazepine)
What is important about lithium metabolism?
it is metabolized by the kidney; so you may have to adjust the dose based on renal function
Which tests should be ordered on a patient prior to starting lithium? (5)
1) CBC
2) Thyroid
3) basic chemistries (kidney function)
4) ECG baseline
5) pregnancy test (if female)
Do blood levels of always correlate with efficacy?
NO… as in SSRIs…
BUT…
clozapine, lithium, valproic acid, and carbamazepine levels DO correlate with efficacy and they should be monitored (as some like lithium) have a very narrow therapeutic window
What is the therapeutic range of lithium? toxic? lethal?
therapeutic: 0.6-1.2
toxic: >1.5
lethal: > 2
Who should get lithium?
It should be cautiously started/monitored for at least 1 year following an acute manic episode and if asymptomatic start to taper them off…
Is it safe for a patient on lithium to be taking ibuprofen?
it should be carefully watched… NSAIDs block lithium excretion and cause levels to build up
why should a patient not stop taking lithium cold turkey?
lithium has been proven to decrease suicide… BUT if stopped suddenly… there is an increased risk of relapse and suicide
Name some medications/conditions that would effect lithium levels… and what would it do to the levels of lithium?
NSAIDs dehydration salt deprivation sweating (salt loss) thiazide diuretics impaired renal function
ALL cause an increase in lithium levels!
What is one weird side effect of lithium that can be advantageous when combined with clozapine? (an atypical antipsychotic)
Lithium can cause leukocytosis… which balances out clozapines tendency to cause agranulocytosis
What is carbamazepine useful for treating? (3)
1) mixed episodes
2) rapid cycling bipolar
3) DOC for trigeminal neuralgia
What is the MOA of carbamazepine?
blocks sodium channels thus inhibiting action potentials
What should you monitor on pts on carbamazepine?
CBC (can cause leukopenia, hyponatremia, agranulocytosis etc) and LFTs (both before and while on med)… recall it tends to induce CYP450 so watch out for the female girl on birth control with a history of seizures (recall the “autoinduction of metabolism”)
What is a potentially dangerous side effect of both carbamazepine and valproic acid that starts as a skin rash?
Stevens-Johnson Syndrome!
Why would you do a pregnancy test on a young female before starting lithium or carbamazepine?
Lithium –> ebsteins anomaly
Carbamazapine –> neural tube defects
What is Valproic Acid useful in treating? (2)
1) mixed episodes of bipolar
2) rapid cycling bipolar
* just like carbamazepine
What is the normal therapeutic range for valproic acid?
Recall: valproic acid, lithium, carbamazepine, and clozapine all have specific levels that should be monitired and correlate with efficacy
50-150 mg/mL
which drug is unique in that it actually helps treat bipolar depression?
Lamotrigine!!! (although its not very useful for acute mania or preventing mania)
What is the MOA of lamotrigine?
works on sodium channels that modulate glutamate and aspartate
What is a serious side effect that actually effects 10% of those taking lamotrigine? and when is it most likely to occur?
Stevens Johnson Syndrome! most likely to occur within the first 4-6 weeks… risk is minimized by starting really low and increasing slow…
dizziness, sedation, headaches and ataxia are also common
What is the interplay between valproic acid and lamotrigine if taken at the same time?
Valproate will increase lamotrigine levels
and
lamotrigine will decrease valproate levels
V increases L… increasing L will decrease V… V down, L up is the bottom line
Random Drug: Topiramate… what is it useful for?
helps with impulse control disorder and anxiety
often used as a weight loss drug
most limiting side effect is cognitive slowing
