107. Mood Stabilizers

Question 1

What are the 3 goals of a mood stabilizer?

What is the broad mechanism of action for a mood stabilizer?

Answer 1

1. Treat manic episodes
2. Treat depressive episodes without causing mania
3. Prevent manic/depressive episodes

Mech: Decrease Glu (excitatory) and Increase GABA (inhibitory)

Question 2

Lithium

• mechanism
• metabolism/excretion
• monitoring
• interactions

Answer 2

• alters activity of several NTs via intracellular transduction systems
• excreted unchanged by kidney (no liver)
• NARROW THERAPEUTIC WINDOW (0.6-1.2mEq/L)

drugs that raise Li: NSAIDs, diuretics, ACEi, CCBs, Metronidazole, Tetracycline
drugs that lower Li: not important (Acetazolamide)

Question 3

Side effects of Li or Signs of Li Toxicity

Answer 3

Renal: polyuria, polydipsia (impaired concentrating ability - interferes with ADH - causing nephrogenic diabetes insipidus), can rarely cause renal insufficiency
CNS: Sedation, impaired cognition, tremor, ataxia, dysarthria
Endocrine: hypothyroidism
Cardiac: conduction problems (bradycardia, SA block)
GI: increased appetite, weight gain, GI upset, N/V/D
Skin: acne/rash/alopecia
Birth Defects: Ebstein’s Anomaly (dysplastic tricuspid valve) - still relatively safe in pregnancy (only slight increase)

Question 4

How would you tx Li Toxicity?

What are the clinical uses of Li?
What is LI not good for

Answer 4

Stop Li and rehydrate with normal saline (dialysis if severe)

• tx of mania/maintenance tx
• BPD (helps with depression too)
• decreases risk of suicide!
• takes 1-3wks for effect
• only 50% respond on monotx alone - need adjunct

Less effective: mixed mood episodes, rapid cycling, substance abuse

Question 5

What anticonvulsants have uses as mood stabilizers? What are their key uses and SE as mood stabilizers?

Answer 5

1. Valproate (blocks Na/Ca/Glu, increases GABA)
   - better for mania, worse for BPD than Li
   - SE: weight gain, GI problems, sedation, ataxia, alopecia (rare: hepatotoxicity, pancreatitis, thrombocytopenia), NTDs!
2. Carbamazepine (blocks Na, increases GABA)
   - use for acute mood episodes, maintenance
   - SE: weight gain, sedation, ataxia, rash (rare: agranulocytosis/aplastic anemia, hepatitis, hypoNa)
3. Oxcarbazepine (blocks Na, increases GABA)
   - similar to carbamazepine but less SE
4. Lamotrigine
   - use for maintenance, BPD (not acute mania - opposite of valproate)
   - SE: SJS/hypersensitivity rash

Question 6

What other class of drugs can function as mood stabilizers? Which diseases are they best equipped to treat?

Answer 6

ATYPICAL ANTIPSYCHOTICS

- manic episodes&raquo_space; BPD&raquo_space; maintenance