Lithium Carbonate

Aka: Lithium Carbonate, Lithium, Eskalith, Lithobid

1. Indication
   1. Bipolar Disorder
2. Contraindications
   1. Pregnancy
      1. Associated with Ebstein Anomaly when exposure in first trimester
3. Pharmacokinetics
   1. Lithium is a simple salt that is excreted and not metabolized
   2. Steady state reached in 5 days
      1. Check Lithium levels 5 days after starting dose or changing dose
   3. Therapeutic Trough levels
      1. Acute mania: 1.0 to 1.2 meq/L
      2. Maintenance Bipolar Disorder: 0.8 to 1.0 meq/liter
      3. Increasing dose 300 mg/day raises level 0.2 meq/L
4. Dosing
   1. Effective dose: 900 to 1800 mg per day divided twice daily (or 3-4 times daily)
   2. Start: 300 mg orally twice daily
      1. May adjust dose every 2-3 days as tolerated
5. Adverse Effects
   1. Polyuria
   2. Hypothyroidism
      1. Often reversible on stopping Lithium
      2. Higher Prevalence in women and with increasing age
   3. Weight gain
   4. Fine Tremor
   5. Withdrawal symptoms on stopping
      1. More common than with Valproate or Lamotrigine
6. Adverse Effects: Toxicity
   1. Nausea and Vomiting
   2. Diarrhea
   3. Ataxia
   4. Coma
   5. Death
7. Toxicity
   1. Precaution
      1. Toxicity is dose dependent and overdose can be lethal
   2. Pregnancy
      1. Highly Teratogenic
   3. Cerebellar Signs or symptoms
   4. Mechanism
      1. Poor therapeutic window
      2. Renal excretion
8. Drug Interactions
   1. Diuretics
   2. NSAIDs
   3. ACE Inhibitors
9. Monitoring
   1. Serum Lithium level
      1. Day 5 after starting Lithium
      2. Then every 1-2 weeks initially
      3. Then every 3-6 months
      4. Also check serum levels before and 5 days after dose changes
   2. Other labs
      1. Schedule
         1. Baseline
         2. Month 3
         3. Month 6
         4. Every 6 to 12 months thereafter
      2. Thyroid Stimulating Hormone (TSH)
      3. Renal Function tests
         1. Serum Creatinine
         2. Blood Urea Nitrogen