Bipolar Disorder Medications Flashcards
What are bipolar I and bipolar II disorder characterized by?
Bipolar I– Acute mania
Bipolar II – Acute hypomania
Both – Bipolar depression or Bipolar maintenance
Why should bipolar disorder never be treated with an anti-depressant alone?
You could flip them into a manic episode! Always be sure the person takes a mood stabilizer along with the antidepressant for bipolar disorder
What is the firstline treatment for bipolar disorder?
Lithium
List some of the beneficial effects of Lithium for bipolar patients
Effective for both acute mania and bipolar depression
Reduces risk of suicide in people with bipolar I
Good maintenance treatment, preventing mania and depression
Lithium MOA and Effects on NTs
MOA unclear
Increases effects of 5-HT
Decreases turnover of NE and DA
Increase Ach synthesis
Lithium
Absorption and Blood-Protein Binding
Well absorbed orally
Does NOT bind blood proteins
Lithium
Excretion
100% renal excretion
Lithium
Interaction with Carbonic anhydrase inhibitor diuretics
Those diuretics work in the PCT. They are acetazolamide, methazolamide, and dichlorphenamide.
They result in an increase in lithium excretion, thus decreasing Li+ blood levels.
Lithium
Interaction with Osmotic Diuretics
These diuretics work in the PCT. Act by increasing tubular fluid osmolality. Mannitol.
They result in an increase in lithium excretion, thus decreasing Li+ blood levels.
Lithium
Interaction with Loop Diuretics
Block the NKCC2 channel in the thick ascending loop. Furosemide.
May increase or decrease Li+ excretion. Effects are debated
Lithium
Interaction with Thiazide Diuretics
Block the Na+/Cl- transporter in the DCT. Hydrochlorothiazide.
Decrease lithium excretion, leading to an increase in blood levels of Lithium
Lithium
Interaction with K+ Sparing Diuretics
Act at the collecting duct to antagonize aldosterone receptors. Spironolactone and amiloride.
Decrease lithium excretion, thus resulting in higher lithium blood levels.
Lithium
Interaction with ACE inhibitors and ATII receptor antagonists
Inhibit ATII production, leading to less aldosterone, thus more Na+/Li+ reabsorption at collecting duct
Overall increase in lithium blood levels
How does hyponatremia effect lithium levels?
Body will try to hang onto more Na+ (and thus Li+), so blood lithium levels will increase
How does pregnancy affect lithium levels? How will this affect your dosing of lithium throughout and after labor?
Decrease lithium levels (higher excretion).
During pregnancy, give lithium at a higher dose. Hold the lithium during labor, then give her lithium at HALF dose after delivery.
How does renal impairment affect lithium levels?
Increase blood lithium levels
List some common side effects of lithium
Hypothyroidism Nausea Diarrhea Fine tremor Decreased concentration Sedation Weight gain
What is a serious side effect of lithium, seen after years of taking lithium?
Nephrogenic diabetes insipdus (10 or more years)
Symptoms of Lithium Toxicity
Mild – Nausea, Vomiting, Diarrhea, Lethargy, Drowsiness, Muscle weakness, coarse hand tremor
Moderate– Confusion, Myoclonic twitch, dysarthria, ataxia, ECG changes
Severe- impaired consciousness, coma, seizures, syncope
Before starting a patient on lithium, what tests should you check?
TSH
Renal function
ECG if pt is over 50yo
Weight
Pregnancy
Valproic acid is AKA…
Divalproex Sodium (Depakote)
Depakote
Absorption and Protein Binding
100% oral absorption
Highly protein bound, which may cause drug-drug interactions
Depakote
Metabolism
Hepatic metabolism
Inhibits the glucoronidase system, which may affect the hepatic metabolism of other drugs like carbamazepine
Depakote
Side Effects
Nausea/Vomiting Diarrhea Tremor Sedation Weight Gain
Less common: ataxia, headaches, dizziness, thrombocytopenia, hyperammonemia, hepatotoxicity
Hepatic Side Effects of Depakote
Mild increase in LFTs
Hepatotoxicity (may be fatal in children under 2 who are on many antiseizure meds)
Hyperammonemia
Depakote
What tests should you check before starting?
LFTs
Platelets
Weight
Pregnancy test
Carbamazepine
Protein binding
Moderate protein binding (70-80%)
Carbamazepine
Metabolism
Hepatic
Induces its own metabolism by P450 system (may also induce metabolism of other drugs)
Carbamazepine
Side Effects
Nausea, vomiting
Neuro side effects are caused by a metabolite of Carbamazepine (dizziness, sedation, ataxia, diplopia)
Lamotrigine
Protein binding
Low protein binding
Lamotrigine
Metabolism
Primarily hepatic by glucoronidation. Lamotrigine metabolism may be induced by carbamazepine, or inhibited by depakote
Lamotrigine
Side Effects
Nausea, vomiting
Rash –> could be benign or Steven Johnsons Syndrome, so you need to treat it
2nd Gen AntiPsychotics
Indication
Used in treating severe bipolar mania (only when the patient is psychotic or exhibits suicidal/dangerous behavior)
Used in combination with either lithium or depakote for severe bipolar mania
Which bipolar med has the highest risk of birth defects?
Depakote
Risk of neural tube defects is 3-5% with depakote
Which bipolar med has the lowest risk of birth defects?
Lamotrigine
Lamotrigine
Indications
Used to prevent acute manic episodes (in maintenance treatment), but is NOT used to treat acute mania or hypomania
What drug class may be used as an adjunct for acute mania or hypomania treatments (never used on its own for mania)?
Benzodiazepines
