Important: This is informational content only. Always consult Dr. Ambrish Singal or your psychiatrist before starting, stopping, or changing any medication.
What is Lithium?
Lithium is the oldest and most well-established mood stabilizer. It remains the first-line treatment for bipolar disorder and is the only medication proven to reduce suicide risk in mood disorders. Requires regular blood level monitoring.
How It Works
The exact mechanism is not fully understood. It modulates neurotransmitter release, affects second messenger systems (inositol pathway), enhances serotonin function, and has neuroprotective effects. It influences gene expression through glycogen synthase kinase-3 (GSK-3) inhibition.
Uses
How This Drug Starts Working
Anti-manic effects begin within 5-7 days. Full mood stabilization takes 2-3 weeks. Suicide prevention effect may take months.
Week-by-Week Timeline
Day 1-3: Therapeutic blood levels being established. Common initial effects: nausea, fine tremor, increased thirst and urination.
Day 5-7: Manic symptoms beginning to reduce. Agitation decreasing. Sleep improving.
Week 2: Significant reduction in manic symptoms. Mood stabilizing. Irritability reducing.
Week 3-4: Full anti-manic effect. Mood within normal range. Side effects stabilizing.
Month 2+: Anti-suicidal and neuroprotective effects building. Long-term mood stability establishing.
What Changes First?
Sleep normalizes first, then agitation reduces, then elevated/irritable mood returns to normal, then judgment improves. Full prophylactic (prevention) effect takes 6-12 months to be properly assessed.
Why Does It Take Time?
Lithium works through multiple mechanisms: GSK-3 inhibition promotes neuroprotection, inositol depletion stabilizes second messenger systems, and gene expression changes strengthen mood-regulating circuits. These biological changes take time to fully establish.
Complete Dosage Guide
How to Take
Take in divided doses (usually twice daily) or as extended-release once daily. Take with food to reduce nausea. Take with a FULL glass of water.
Starting Dose
300mg 2-3 times daily (IR) or 450-900mg once daily (ER). Target is based on BLOOD LEVELS, not dose.
Dose Increases
Dose adjusted based on serum lithium levels drawn 12 hours after last dose. Target: 0.6-1.2 mEq/L for acute mania, 0.6-0.8 mEq/L for maintenance.
Maximum Dose
Determined by blood level, not mg dose. Levels above 1.2 mEq/L increase toxicity risk significantly.
When to Take
12-hour trough levels are the standard measurement. Take doses consistently so that blood tests are interpretable. Extended-release reduces peak-related side effects (nausea, tremor, frequency).
If You Miss a Dose
Take it as soon as you remember. If close to next dose, skip and continue. NEVER double up (toxicity risk). Consistent dosing is especially important for lithium because of its narrow therapeutic window.
Food & Drink
Maintain CONSISTENT salt and water intake. Sudden changes in sodium (low-salt diet, heavy sweating, diarrhea) can dramatically change lithium levels. Stay well-hydrated (2-3L water daily). Caffeine may reduce lithium levels slightly.
How Long to Take
Usually LIFELONG for bipolar disorder. Lithium is the most proven medication for preventing bipolar relapse and reducing suicide risk. Never stop without medical guidance.
Dosage by Age Group
adult
Start 300mg 2-3 times daily. Target serum level: 0.6-1.2 mEq/L (acute mania: 0.8-1.2; maintenance: 0.6-0.8).
child
Ages 12+: Weight-based dosing. Start low, target same serum levels.
elderly
Start 150-300mg daily. Lower target levels (0.4-0.6 mEq/L). Increased sensitivity.
Special Populations
Pregnancy
Category D. Associated with Ebstein's anomaly (cardiac defect). Avoid in first trimester if possible.
Kidney Conditions
CAUTION. Lithium is entirely renally excreted. Dose reduction needed. Avoid if possible in renal disease.
Liver Conditions
No specific adjustment needed (not hepatically metabolized).
Side Effects
Common
- Tremor
- Thirst (polydipsia)
- Frequent urination (polyuria)
- Weight gain
- Nausea
- Diarrhea
- Cognitive dulling
- Acne
Serious
- Lithium toxicity (narrow therapeutic window)
- Hypothyroidism
- Nephrogenic diabetes insipidus
- Renal impairment (long-term)
- Cardiac arrhythmias
- Ebstein's anomaly (if used in pregnancy)
What You Should Know
Overdose Risks
DANGEROUS. Lithium toxicity causes tremor, confusion, ataxia, seizures, renal failure, and cardiac collapse. Toxicity can occur at levels >1.5 mEq/L. Hemodialysis may be needed.
Safe Discontinuation
Taper over 2-4 weeks minimum. Abrupt discontinuation significantly increases relapse risk, especially for mania. Some evidence suggests relapse risk is higher after abrupt vs gradual discontinuation.