L3- Bipolar Treatment

Question 1

(1) treats acute bipolar manic episodes

(2) is prophylactic treatment to prevents manic episodes

Answer 1

1/2- Lithium

Question 2

describe lithium MOA

Answer 2

• brain requires Inositol (for Gq cell signalling)
• Inositol doesn’t cross BBB, must be made in brain
• Li inhibits Inositol synthesis in the CNS via Inositol mono-/poly-phosphatase inhibition (no creation of PIP2 –> no Gq signalling)

-this will inhibit adrenergic, muscarinic, and serotonergic transmission

Question 3

what does it mean that Lithium has uncompetitive action

Answer 3

only neurons with active receptors are affected by lithium

Question 4

list the many AEs of Lithium

Answer 4

-tremors, sedation, ataxia, aphasia, seizures

• weight gain, hypothyroidism
• edema, *Nephrogenic DI
• dermatitis, alopecia
• leukocytosis

Question 5

Lithium induced Nephrogenic DI:

• (1) mechanism
• (2) Tx

Answer 5

1- Li prevents translocation of aquaporins from intracellular to cell membrane

2- discontinue Li –> if not Tx w/ amiloride –> thiazides, NSAIDs as other options

Question 6

(T/F) Lithium is never used in pregnant patients

Answer 6

F- category D, benefits to mother must outweigh the risks to fetus

Question 7

list the signs of Lithium acute intoxication

Answer 7

• vomiting, profuse diarrhea
• coarse tremor, ataxia
• coma
• convulsions

Question 8

the following are monitored in patients taking lithium

Answer 8

• serum [Li]
• renal function
• thyroid function

Question 9

list the main drug interactions that should be avoided with Lithium therapy

Answer 9

Reduced Li clearance with use of:

thiazides, NSAIDs, ACEIs, ARBs

Question 10

list alternative bipolar treatments

Answer 10

(not Lithium)
Antiepileptics: valproate (monitor liver, CBC), carbazepine (monitor CBC) [+ lamotrigne]

Atypical antipsychotics