Dosing and uses of Eskalith, Lithobid (lithium)
Adult dosage forms and strengths
tablet, extended release
- 300mg
- 450mg
tablet
- 300mg
capsule
- 150mg
- 300mg
- 600mg
solution
- 8mEq/5mL
Bipolar Disorder
Immediate release: 900-2400 mg/day PO divided q6-8hr
Extended release: 900-1800 mg/day PO divided q12hr
Lower initial dosage may be used to minimize adverse drug reactions
Serum lithium should be monitored 12 hours after dose, twice weekly until serum concentration and clinical condition stabilize, and every other month thereafter
Desirable range for serum lithium: 0.6-1.2 mEq/L; although higher serum concentrations may be needed, not to exceed 1.5 mEq/L
Huntington's Disease (Orphan)
Lithium citrate tetrahydrate (in reverse micelle formulation)
Orphan indication sponsor
- Medesis Pharma; L'Oree des Mas, 34 670 Baillargues, France
Administration
Preferably taken with food
Pediatric dosage forms and strengths
tablet, extended release
- 300mg
- 450mg
tablet
- 300mg
capsule
- 150mg
- 300mg
- 600mg
solution
- 8mEq/5mL
Bipolar Disorder (Off-label)
<6 years: Safety and efficacy not established
6-12 years: 15-60 mg/kg/day PO divided q6-8hr; not to exceed adult dosage
>12 years: Immediate release, 900-2400 mg/day PO divided q6-8hr; extended release, 900-1800 mg/day PO divided q12hr
Geriatric dosage forms and strengths
Dosing in elderly patients should be cautious, usually starting at low end of range
Elderly patients often respond to reduced dosage and may exhibit signs of toxicity at serum concentrations ordinarily tolerated by younger patients
Eskalith, Lithobid (lithium) adverse (side) effects
>10%
Leukocytosis (most patients)
Polyuria/polydypsia (30-50%)
Dry mouth (20-50%)
Hand tremor (45% initially, 10% after 1 year of treatment)
Confusion (40%)
Decreased memory (40%)
Headache (40%)
Muscle weakness (30% initially, 1% after 1 year of treatment)
Electrocardiographic (ECG) changes (20-30%)
Nausea, vomiting, diarrhea (10-30% initially, 1-10% after 1-2 years of treatment)
Hyperreflexia (15%)
Muscle twitch (15%)
Vertigo (15%)
1-10%
Extrapyramidal symptoms, goiter (5%)
Hypothyroidism (1-4%)
Acne (1%)
Hair thinning (1%)
Frequency not defined
Coma
Lethargy
Seizures
Renal toxicity
Warnings
Black box warnings
Toxicity is closely related to serum lithium concentrations and may occur at dosages close to therapeutic levels; monitor therapy by measuring serum lithium
Equipped facilities should be identified before initiation of therapy to provide prompt and accurate serum lithium concentration data
Contraindications
Documented hypersensitivity
Severe cardiovascular disease
Pregnancy in 1st trimester
Unstable renal function, sodium depletion, severe dehydration
Severe debilitation
Cautions
Cardiovascular disease; reports of possible association between lithium treatment and unmasking of Brugada syndrome (abnormal ECG and risk of sudden death)
Use with caution in patients with thyroid disease
Narrow therapeutic index
Risk of nephrogenic diabetes insipidus; such patients should be carefully managed to avoid dehydration with resulting lithium retention and toxicity; condition is usually reversible when lithium is discontinued
Lithium-sensitive patients may experience toxicity symptoms with serum lithium concentrations of 1-1.5 mEq/L
Lithium toxicity is closely related to serum levels and can occur at therapeutic dosages; if manifestations of toxicity occur, discontinue for 24-48 hours, then resume at lower dosage
Mainitain geriatric patients on dosages that produce serum lithium concentrations at lower end of desired range
May cause central nervous system (CNS) depression and impair ability to operate heavy machinery
Hypercalcemia reported with or without hyperparathyroidism; women and older patients are possibly at greater risk; onset does not appear to be associated with duration of therapy
Monitor changes in renal function; chronic therapy may diminish renal concentrating ability; usually reversible when lithium therapy discontinued
Use caution in debilitated patients; may increase risk of lithium toxicity
Use with caution in patients at risk for suicide
The risk of lithium toxicity is increased in patients with significant renal or cardiovascular disease, severe debilitation or dehydration, or sodium depletion, and for patients receiving prescribed medications that may affect kidney function, such as angiotensin converting enzyme inhibitors (ACE inhibitors), angiotensin receptor blockers (ARBs), diuretics (loops and thiazides) and NSAIDs; for these patients, consider starting with lower doses and titrating slowly while frequently monitoring serum lithium concentrations and signs of lithium toxicity
Cases consistent with nephrotic syndrome reported with use of lithium; discontinuation of lithium in patients with nephrotic syndrome has resulted in remission of nephrotic syndrome
Routine urinalysis and other tests may be used to evaluate tubular function (e.g., urine specific gravity or osmolality following a period of water deprivation, or 24-hour urine volume) and glomerular function (e.g., serum creatinine ,creatinine clearance, or proteinuria); during lithium therapy, progressive or sudden changes in renal function, even within normal range, indicate the need for re-evaluation of treatment
An encephalopathic syndrome (characterized by weakness, lethargy, fever, tremulousness and confusion, extrapyramidal symptoms, leukocytosis, elevated serum enzymes, BUN, and FBS) has reported in a few patients treated with lithium plus a neuroleptic, most notably haloperidol; in some instances, the syndrome was followed by irreversible brain damage; because of possible causal relationship patients receiving such combined therapy or patients with organic brain syndrome or other CNS impairment should be monitored closely for early evidence of neurologic toxicity and treatment discontinued promptly if such signs appear; encephalopathic syndrome may be similar to or the same as Neuroleptic Malignant Syndrome (NMS)
Lithium may prolong effects of neuromuscular blocking agents; neuromuscular blocking agents should be given with caution to patients receiving lithium
Pregnancy and lactation
Pregnancy category: d
Lactation: Drug is excreted in breast milk; use not recommended
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Eskalith, Lithobid (lithium)
Mechanism of action
Inhibits postsynaptic D2 receptor supersensitivity
Alters cation transport in nerve and muscle cells and influences reuptake of serotonin or norepinephrine
Inhibits phosphatidylinositol cycle second messenger systems
Absorption
Bioavailability: Immediate release, 95-100%; extended release, 60-90%
Onset: Initial antimanic effect, 5-7 days; full effect, 10-21 days
Peak serum time: Immediate release, 0.5-2 hr; extended release, 4-12 hr
Peak plasma concentration: 0.4-0.9 mEq/L
Steady-state therapeutic plasma concentration: 0.5-1.3 mEq/L
Distribution
Vd: Approximates total body water (0.7-1 L/kg)
Metabolism
Not metabolized
Elimination
Half-life: 18-24 hr; up to 36 hr with advanced age or renal impairment
Dialyzable: Yes (hemodialysis, 50-90 mL/min; peritoneal dialysis, 13-15 mL/min)
Renal clearance: 20-40 mL/min
Excretion: Urine (95-99%)
