Drug Guide
Lithium Citrate
Classification
Therapeutic: Mood stabilizer, Antimanic agent
Pharmacological: Alkali metal, Salt of lithium
FDA Approved Indications
- Bipolar disorder (manic episodes, maintenance)
Mechanism of Action
Lithium's exact mechanism is unknown, but it is thought to influence reuptake of neurotransmitters such as norepinephrine and serotonin, and to modulate second messenger systems, stabilizing neuronal activity.
Dosage and Administration
Adult: Initial: 300 mg 2-3 times daily; titrate based on serum levels and clinical response. Typical maintenance dose: 900-1800 mg/day in divided doses.
Pediatric: Use is less common; dose initiation and adjustment should be guided by a pediatric psychiatrist.
Geriatric: Start with lower doses due to decreased renal function; careful monitoring required.
Renal Impairment: Use caution; dose adjustments needed, serum levels should be monitored closely.
Hepatic Impairment: No specific adjustments, but cautious use advised.
Pharmacokinetics
Absorption: Well absorbed from gastrointestinal tract.
Distribution: Widely distributed, crosses blood-brain barrier, minimal protein binding.
Metabolism: Not metabolized; excreted unchanged.
Excretion: Primarily via kidneys through glomerular filtration and tubular reabsorption.
Half Life: Less than 24 hours, varies with renal function.
Contraindications
- Renal disease, significant cardiovascular disease, dehydration, sodium depletion, pregnancy (due to fetus risk).
Precautions
- Monitor renal and thyroid function, hydration status, and serum lithium levels regularly. Use with caution in elderly and those on medications affecting lithium levels.
Adverse Reactions - Common
- Fine hand tremor (Common)
- Polyuria, thirst (Common)
- Gastrointestinal discomfort (Common)
Adverse Reactions - Serious
- Toxicity (levels above therapeutic range) (Serious)
- Nephrogenic diabetes insipidus (Rare)
- Thyroid dysfunction (hypothyroidism) (Less common)
- Serious neurological effects (seizures, coma) (Rare, but potentially fatal)
Drug-Drug Interactions
- Diuretics (especially thiazides), NSAIDs, ACE inhibitors, ARBs, certain antidepressants (SSRIs, SNRIs)
Drug-Food Interactions
- Dehydrating foods or excessive salt intake can affect lithium levels.
Drug-Herb Interactions
N/ANursing Implications
Assessment: Regularly assess mental status, mood, hydration, renal and thyroid function, and serum lithium levels.
Diagnoses:
- Risk for electrolyte imbalance, anxiety, altered thought processes.
Implementation: Administer with food to minimize gastrointestinal upset, monitor serum levels periodically, educate about maintaining consistent salt and fluid intake.
Evaluation: Therapeutic response indicated by mood stabilization, absence of manic/depressive episodes, and serum levels within therapeutic range.
Patient/Family Teaching
- Maintain consistent salt and fluid intake.
- Report signs of toxicity: nausea, vomiting, diarrhea, drowsiness, muscle weakness, tremor.
- Avoid dehydration and excessive sweating.
- Adhere to scheduled blood tests for lithium levels, renal, and thyroid function.
Special Considerations
Black Box Warnings:
- Lithium toxicity can be fatal if not detected early.
Genetic Factors: Genetic predisposition may influence susceptibility to toxicity.
Lab Test Interference: Lithium levels may be affected by serum glucose and protein levels.
Overdose Management
Signs/Symptoms: Nausea, vomiting, diarrhea, ataxia, tremors, drowsiness, seizures, coma.
Treatment: Discontinue lithium immediately, provide supportive care, consider gastric lavage, administer activated charcoal if ingestion was recent, correct electrolyte imbalances, and perform hemodialysis in severe toxicity.
Storage and Handling
Storage: Store at room temperature, away from moisture and heat.
Stability: Stable under recommended storage conditions for the duration of the expiration date.