Mood Stabilizers

Question 1

What are the three main categories of mood stabilizers? Give examples in each.

Answer 1

Lithium, anti-convulsants (lamotrigine, gabapentin), and atypical anti-psychotics (lanzapine)

Question 2

Which three mood stabilizers are relatively safe to use in pregnancy (all others are category D an not)?

Answer 2

Lamotrigine, gabapentin and olanzapine

Question 3

What are Lithium’s 3 MOAs?

Answer 3

1. Blocks the enzyme inositol-1-phosphatase, therefore blocks the phosphatidylinosytol (PI)-IP3-DAG signal pathway
2. Uncoupling receptor with G protein, by inhibiting the activation of adenylyl cyclase (Gs receptor, such as TSH, ADH V2 receptor)
3. It can substitute for sodium (lithium is a monovalent cation) in generating action potential and exchanging of Na+-Na+.

Question 4

How can lithium cause the ADR of nephrogenic DI?

Answer 4

Impair ADH on V2 receptor, downregulate aquaporin-2 protein, disregulate amiloride-sensitive sodium channel)

Question 5

How can lithium cause the ADR hypothyroidism?

Answer 5

Inhibits thyroid hormone release (TSH receptor is Gs) and 5’ deiodinase (T4 conversion). Most happen during the first year use of lithium

Question 6

What is the teratogenicity effect of lithium?

Answer 6

Ebstein’s anomaly: malformed tricuspid valve in which the tricuspid posterior leaflet attaches to the wall of RV

Question 7

Why is lithium contraindicated in SIck Sinus Syndrome (sinus pause/arrest, sinus bradycardia)?

Answer 7

Because lithium suppresses SA node.

Question 8

Lithium has a very narrow therapeutic window. What are the acute signs of lithium toxicity?

Answer 8

Anorexia, vomiting, gross tremor, ataxia, confusion, and sleepiness

Question 9

What are the later signs of lithium toxicity?

Answer 9

impaired consciousness, nystagmus, muscle twitching, hyperreflexia, convulsions, cardiac arrhythmias, hypotension impaired renal function

Question 10

Lithium is excreted mostly (95%) in the _____.

Answer 10

urine

Question 11

3 types of drugs increase blood lithium levels by impairing its renal excretion and therefore causes lithium toxicity. What are these 3 types?

Answer 11

Thiazides
NSAID: ibuprofen, naproxen, indomethacin, COXII inhibitors except aspirin, acetaminophen, sulindac
ACEI

Question 12

Lithium is preferentially excreted in sweat. What conditions facilitate Na+ re-absorption and therefore lead to increased re-absorption of lithium and toxicity?

Answer 12

Dehydration (exercise)

Question 13

What are the 3 main mood disorders lithium is used to treat?

Answer 13

1. Bipolar Affective Disorder
2. Major depression (with antidepressants)
3. Schizophrenia (with antipsychotics)

Question 14

What drugs are used in manic phase treatment?

Answer 14

Lithium, Valproic Acid, or Atypical Antipsychotics

Question 15

What drugs are used in depressed phase treatment?

Answer 15

Lithium plus antidepressant

Question 16

What drugs are used in maintenance of mood disorders?

Answer 16

Lithium or Valproic Acid