Section 02 · Monograph
Lithium
Reviewed Nov 2026FDA label
Lithobid / genericMood stabilizer
- Forms
- Cap: 150, 300, 600mg | ER tab: 300, 450mg
- Dose
- Cluster prevention (off-label): 600-900mg/day; target level 0.4-0.8 mEq/L
- MOA
- Mechanism unclear; modulates second-messenger signaling
Black Box Warning
- Lithium toxicity is closely related to serum lithium levels and can occur at doses close to therapeutic levels; facilities for prompt and accurate serum lithium determinations should be available before initiating therapy
Indications
- Bipolar disorder (acute mania and maintenance)FDA-labeled
Off-Label Uses
- Cluster headache prophylaxisOff-label
- Hypnic headacheOff-label
Mechanism of Action
- Mechanism not fully established; modulates second-messenger signaling (inositol, GSK-3) and neurotransmission
Full Dosing
Adult / usual
- Cluster prophylaxis: commonly 600-900mg/day in 2-3 divided doses; target serum level about 0.4-0.8mEq/L (sample 12 hours after last dose)
- Titrate slowly; maintain consistent hydration and sodium intake
Contraindications
- Significant renal or cardiovascular disease, severe debilitation or dehydration
- Sodium depletion and concomitant diuretic use (relative)
- Hypersensitivity
Drug Interactions
- NSAIDs, ACE inhibitors, ARBs and thiazides raise lithium levels
- Verapamil, diltiazem, carbamazepine and phenytoin: neurotoxicity even at normal levels
- Caffeine lowers levels
Adverse Effects
- Tremor, polyuria and polydipsia
- Hypothyroidism, nephrogenic diabetes insipidus
- Nausea, diarrhea, weight gain
- Lithium toxicity (coarse tremor, ataxia, confusion, seizures)
- Chronic kidney disease
Monitoring Parameters
- Serum lithium level, creatinine/eGFR, TSH and calcium
- Baseline ECG in at-risk patients
Pregnancy & Lactation
- Cardiac malformation risk (Ebstein anomaly); dosing changes are needed during pregnancy
- Excreted in milk; breastfeeding generally not recommended