88B Mood stabilizers Flashcards
(29 cards)
Mood stabilizer treats…
manic episodes
depressive episodes without precipitating mania (unlike antidepressants)
Prevents manic and depressive episodes
Antidepressants in bipolar conditions
Use with caution
Don’t treat manic episodes
can cause mania in bipolar patients
Mood stabilizers mechanism of action
Not completely understood
decreases glutamate activity (excitatory)
increases GABA activity (inhibitory)
3 types of mood stabilizers
1) lithium
2) anticonvulsants
3) antipsychotics
Lithium mechanism
Not understood
not synaptic
via Intracellular signal transduction systems –> alters several nts
Lithium - kinetics
Excreted unchanged by kidney
not protein bound
no hepatic metabolism
half life of 24 hours (5 days for steady state)
Lithium - dosing, monitoring
1-3 times/day (3 = better tolerance to SA)
check serum levels after 5 days of change 12 hours post dose
TI .6 to 1.2 mEq/L – just a guide for dosing
monitor BUN, creatine, CBC, EKG, Thyroid
Lithium side effects - organ systems
Renal
CNS
Endocrine
Cardiac
GI
Others
Lithium - renal effects
impairs concentrating ability of kidney + blocks ADH activity –> polyuria and polydipsia; diabetes insipidus
Interstitial nephritis and impaired GFR
Lithium - CNS effects
sedation
impaired cognition
tremor (treat with b-blocker)
ataxia
Lithium - Cardiac Effects
conduction issues –> sinus bradycardia and SA block
what birth defect does lithium cause?
Ebstein’s anomaly (dysplastic tricuspid vavle)
Drugs that increase serum lithium levels
NSAIDs
Thiazides
Spironlactone
Triamterene
ACE Inhibitors
Ca-channel blockers
lithium toxicity levels occur as low as ?
1.5
risk with lithium toxicity
permanent neurologic and renal damage –> death
Lithium- what is mild vs moderate toxicity
<2 = mild
>2 = moderate - severe - very severe (>3)
lithium toxicity management
mild - stop drug, rehydrate with normal saline
severe - dialysis
Lithium toxicity causes
drug interaction
dehydration/decreased sodium intake/decreased renal blood flow (heart failure, cirrhosis)
lithium - clinical use
bipolar mania + maintenance (and bipolar depression)
mania > bipolar depression (better than other mood stabilizers though)
takes 1-3 weeks to treat mania though so use another mood stabilizer (or add on)
Usually use mulitple durgs in bipolar
reduces suicide risk
Who is lithium less effective in?
mixed mood episodes
rapid cycling
comorbid substance abuse
Anticonvulsant mechanism of action in bipolar treatment
blocks voltage gated Ca channels and other channels
enhances GABA activity or decreases glutamate activity
list commonly used anticonvulsants in bipolar
Valproic acid (acute mania - most effective and quick)
carbamazepine
oxcarbazepine
lamotrigine
Valproic Acid - use
acute mania and maintenance mania
works quickly
less effective for bipolar depression
valproic acid metabolism
liver
can increase P450 drug levels (lamotrigine)
