2.16: Bipolar Flashcards
When is acute hypomania seen?
Bipolar II
4 Stages of Bipolar disorder that need to be treated? Which type are they seen in?
- Acute Mania: I
- Acute Hypomania: II
- Bipolar depression: I and II
- Bipolar maintenance: I and II
Consensus on how bipolar depression should NOT be treated?
- Should NOT be treated ONLY with an antidepressant
- Fear is it will bring them out of depression and flit into manic episode
- Mood stabilized should be given with antidepressant
First line treatment in bipolar disorder?
Lithium
Onset of lithium?
2 - 3 weeks
What does “better from above than from below” mean?
- Better at treating mania than depression
- This is case with lithium
Which stages does lithium treat?
- Bipolar depression
- Bipolar mania: better at mania
- Maintenance
What does lithium reduce the risk of?
- Suicide
- Effective in BP I, II, and MDD
What drug reduces the risk of suicide in patients?
- Lithium
2. Clozaril
What is 5ht?
Serotonin
Effect of lithium on NTs?
- Increased effects of 5-ht
- Decreased turnover of NE and DA
- Increased synthesis of Ach
Excretion and metabolism of Li?
- 100% renal excretion
- 0 hepatic metabolism
Therapeutic windows of lithium?
Acute mania: .6 - 1.2 meq/L
Maintenance: .6 - .7 meq/L
Absorption and binding of Li?
- Well absorbed in GI tract: peak levels in .5 - 2 hrs
- NO protein binding
Li effects on bipolar disorder?
- Reduces suicide risk
2. Enhances antidepressant effects in MDD
Blood monitoring of Li?
- 20 Hr. halflife
- Blood draw 5 - 7 days after first / new dose
Through draw of Li?
- 12 hours after last dose
How does kidney handle Li?
- Freely filtered in glomerulus
- Reabsorbed with Na in proximal tubule
- Resorbed by principal epithelial cells in Na channel of collecting duct
Drugs involved in urinary alkalization?
“Carbonic anhydrase inhibitors”
- Acetazolamide
- Dichlorphenamide
- Methazolamide
What does carbonic anhydrase do?
- Catalyzes conversion of H2O and CO2 into bicarb and H
- Found in tubule epithelium
- Release H into lumen to combine with bicarb
- Without this H, Bicarb has nothing to combine with and urine is alkalized
Impact of carbonic anhydrase inhibitors on Li?
- Decrease blood [Li]
- Block Bicarb reabsorption in proximal tubule
- Li and Na follow to distal tubule
- Some is reabsorbed, but net loss in urine
What are the osmotic diuretics?
- Mannitol
- Urea
* **Work at proximal tubule
Impact of osmotic diuretics on Li?
- Decrease blood [Li]
- Increase tubule osmolality
- Increased water and Electrolyte (Na/Li) excrtion
Impact of loop diuretics on Li?
- Little to no change
- Furosemide
Impact of thiazide diuretics on Li?
Increase [Li] in blood
Trend of diuretic impact on Li?
- Drugs acting closer to glomerulus, decrease [Li]
- Drugs acting further from glomerulus, increases [Li]
Impact of K sparing diuretics on Li?
- Increased [Li] in blood
- Spironolactone and Amiloride
- ***Amiloride thought to be protective against NDI
What are the K sparing diuretics?
- Spironolactone
2. Amiloride
Impact of ACEIs and ARBs on Li?
Increased [Li] in blood
Impact of dehydration on Li?
Increased [Li] in blood
Impact of pregnancy on Li?
Decreased [Li] in blood
Impact of Na depletion on Li?
Increased [Li] in blood
Impact of renal impairment on Li?
Increased [Li] in blood