Manic Episode:
- 1 week of abnormal and persistently elevated mood. inflated self-esteem, irritability, decreased need for sleep, flights of ideas, poor attention span, high-risk behaviors.
- Bipolar 1: one or more manic or mixed episodes and major depressive episodes
- Bipolar 2: one or more major depressive episodes accompanied by at least one hypomanic episode
- Cyclothymic disorder: Periods of hypomania and depression that don’t meet criteria
- Rapid cycling: Four episodes of mania or depression in one year.
Lithium:
- Lithium is the gold standard for bipolar 1. Not good for unipolar depression, but has anti-suicidal effects in bipolar. Effects take 1-2 weeks. Most use antipsychotics or benzos during this period.
- Initial lithium dose is 600-900mg/day in divided doses and then titrate.
- Lithium has a narrow therapeutic index: 0.8-1.2 mEq/L. A 300 mg increase can increase by 0.3 mEq/L.
- >1.5 is toxic (GI complaints, tremor, altered mental status)
- >2 can be lethal
- Get trough 12 hours after last dose and every 1-2 weeks for 2 months and then every 3-6 months.
- Get CBC, eletrolytes, renal function, thyroid function, urinalysis, ECG, and pregnancy test before starting. Renal function test, thyroid test and urinalysis every 6-12 months
- Lithium toxicity: lethargy, coarse tremor, confusion, seizures, coma and death
- Renal impairment can increase dose
- Avoid in pregnancy
- Drug/Drug Drug/Food Interactions
- Increase Lithium Concentrations: SSRIs, NSAIDs, ACE inhibitors/ARBs, Diuretics: thiazides, spironolactone, furosemide, metronidazole, tetracyclines, topiramate, medicines that affect electrolyte balance
- Decrease Lithium Concentrations: theophylline, caffeine, Sodium bicarbonate and sodium chloride containing products, psyllium or ispaghula husk, urea, mannitol, acetazolamide, salt in food
- Aggravate neurotoxicity: haloperidol, risperidone, clozapine, phenothiazines, SSRIs, sumatriptan, tricyclic antidepressants, Calcium channel blockers, Carbamazepine, phenytoin, Methyldopa
- Lithium can prolong the effects of Neuromuscular blocking agents
- Anything that affects sodium or the kidneys affects lithium
- Adverse effects: weakness, tremor, nausea, acne, hypothyroid, renal issues, polydipsia, hypercalcemia, parathyroid issues, calcium imbalance, confusion, leukocytosis, alopecia, weight gain, slurred speech, seizures
- Lithium alternatives: carbamazepine (rapid cycling), oxcarbazepine (avoids some carbamazepine side effects), valproate without lamotrigine or lamotrigine with divalproex.