Lithium Citrate Drug Information

Lithium is a mood stabilizing agent indicated as monotherapy for the treatment of bipolar I disorder: Treatment of acute manic and mixed episodes in patients 7 years and older Maintenance treatment in patients 7 years and older Lithium is a mood-stabilizing agent indicated as monotherapy for the treatment of bipolar I disorder: Treatment of acute manic and mixed episodes in patients 7 years and older Maintenance treatment in patients 7 years and older

Pre-treatment Screening

Before initiating treatment with lithium, renal function, vital signs, serum electrolytes, and thyroid function should be evaluated. Concurrent medications should be assessed, and if the patient is a woman of childbearing potential, pregnancy status and potential should be considered.

Recommended Dosage See Table 1 for dosage recommendations for acute and maintenance treatment of bipolar I disorder in adult and pediatric patients (7 to 17 years). Obtain serum lithium concentration assay after 3 days, drawn 12 hours after the last oral dose and regularly until patient is stabilized. Fine hand tremor, polyuria, and thirst may occur during initial therapy for the acute manic phase and may persist throughout treatment.

Nausea and general discomfort may also appear during the first few days of lithium administration. These adverse reactions may subside with continued treatment, concomitant administration with food, or temporary reduction or cessation of dosage. Table 1.

Lithium Dosing for Bipolar I Disorder contains 8 mEq lithium ion (Li + ) which is equivalent to the amount of lithium in 300 mg of lithium carbonate. See Table 2 for lithium carbonate and lithium oral solution dose conversion. Table 2.

Lithium Carbonate and

Serum Lithium Monitoring

Blood samples for serum lithium determination should be drawn immediately prior to the next dose when lithium concentration are relatively stable (i.e., 12 hours after previous dose). Total reliance must not be placed on serum concentrations alone. Accurate patient evaluation requires both clinical and laboratory analysis.

In addition to regular monitoring of serum lithium concentrations for patients on maintenance treatment, serum lithium concentrations should be monitored after any change in dosage, concurrent medication (e.g., diuretics, non-steroidal anti-inflammatory drugs, renin angiotensin system antagonist, or metronidazole), marked increase or decrease in routinely performed strenuous physical activity (such as an exercise program) and in the event of a concomitant disease. Patients abnormally sensitive to lithium may exhibit toxic signs at serum concentrations that are within what is considered the therapeutic range. Geriatric patients often respond to reduced dosage, and may exhibit signs of toxicity at serum concentrations ordinarily tolerated by other patients.

Dosage

Adjustments during Pregnancy and the Postpartum Period If the decision is made to continue lithium treatment during pregnancy, monitor serum lithium concentrations and adjust the dosage as needed in a pregnant woman because renal lithium clearance increases during pregnancy. Avoid sodium restriction or diuretic administration. To decrease the risk of postpartum lithium intoxication, decrease or discontinue lithium therapy two to three days before the expected delivery date to reduce neonatal concentrations and reduce the risk of material lithium intoxication due to the change in vascular volume which occurs during delivery.

At delivery, vascular volume rapidly decreases and the renal clearance of lithium may decrease to pre-pregnancy concentrations. Restart treatment at the preconception dose when the patient is medically stable after delivery with careful monitoring of serum lithium concentrations.

Dosage Adjustments for Patients with Renal Impairment

Start patients with mild to moderate impaired renal function (creatinine clearance 30 to 89 mL/min evaluated by Cockcroft-Gault) with dosages less than those for patients with normal renal function. Titrate slowly while frequently monitoring serum lithium concentration and monitoring for the signs of lithium toxicity. Lithium is not recommended for use in patients with severe renal impairment (creatinine clearance less than 30 mL/min evaluated by Cockcroft-Gault).

Clinical Trials Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in clinical practice. Pediatric Patients (7 to 17 years): Bipolar I Disorder: The following findings are based on an 8-week, placebo-controlled study for acute manic or mixed episodes of bipolar I disorder in pediatric patients 7 to 17 years (N=81). Common Adverse Reactions (incidence ≥ 5% and at least twice the rate of placebo): nausea/vomiting, polyuria, thyroid abnormalities, tremor, thirst/polydipsia, dizziness, rash/dermititis, ataxia/gait disturbance, decreased appetite, and blurry vision.

Adverse Reactions Occurring at an Incidence of 2% or More in Lithium-Treated Pediatric Patients: Adverse reactions associated with the use of lithium (incidence of 2% or greater, rounded to the nearest percent, and lithium incidence greater than placebo) that occurred during acute therapy (up to 8-weeks in pediatric patients with bipolar disorder) are shown in Table 3. Table 3: Adverse Reactions Reported in 2% or More or Pediatric Patients on Lithium and That Occurred at Greater Incidence Than in the Placebo Group in the 8-Week Acute Bipolar Trial Adult Patients: The following adverse reactions have been identified following use of lithium. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Central Nervous System: tremor, muscle hyperirritability (fasciculations, twitching, clonic movements of whole limbs), hypertonicity, ataxia, choreoathetotic movements, hyperactive deep tendon reflexes, extrapyramidal symptoms including acute dystonia, cogwheel rigidity, blackout spells, epileptiform seizures, slurred speech, dizziness, vertigo, downbeat nystagmus, incontinence of urine or feces, somnolence, psychomotor retardation, restlessness, confusion, stupor, coma, tongue movements, tics, tinnitus, hallucinations, poor memory, slowed intellectual functioning, startled response, worsening of organic brain syndromes, myasthenic syndromes (rarely). EEG Changes: diffuse slowing, widening of frequency spectrum, potentiation and disorganization of background rhythm. Cardiovascular: conduction disturbance (mostly sinus node dysfunction with possibly severe sinus bradycardia and sinoatrial block), ventricular tachyarrhythmia, peripheral vasculopathy (resembling Raynaud's Syndrome).

ECG Changes: reversible flattening, isoelectricity or rarely inversion of T-waves, prolongation of the QTc interval. Gastrointestinal: anorexia, nausea, vomiting, diarrhea, gastritis, salivary gland swelling, abdominal pain, excessive salivation, flatulence, indigestion. Genitourinary: glycosuria, decreased creatinine clearance, albuminuria, oliguria, and symptoms of nephrogenic diabetes insipidus including polyuria, thirst, and polydipsia.

Dermatologic: drying and thinning of hair, alopecia, anesthesia of skin, chronic follicullitis, xerosis cutis, psoriasis onset or exacerbation, generalized pruritus with or without rash, cutaneous ulcers, angioedema, drug reaction with eosinophilia and systemic symptoms (DRESS) Autonomic Nervous System: blurred vision, dry mouth, impotence/sexual dysfunction. Miscellaneous: fatigue, lethargy, transient scotoma, exopthalmos, dehydration, weight loss, leukocytosis, headache, transient hyperglycemia, hypermagnesemia, excessive weight gain, edematous swelling of ankles or wrists, dysgeusia/taste distortion (e.g., metallic or salty taste), thirst, swollen lips, tightness in chest, swollen and/or painful joints, fever, polyarthralgia, and dental caries.

• Drugs Having Clinically Important Interactions with Lithium Table 4: Clinically Important Drug Interactions with Lithium Diuretics Clinical Impact: Diuretic-induced sodium loss may reduce lithium clearance and increase serum lithium concentrations.
• Intervention: More frequent monitoring of serum electrolyte and lithium concentrations. Reduce lithium dosage based on serum lithium concentration and clinical response Non-Steroidal Anti-inflammatory Drugs(NSAID) Clinical Impact: NSAID decrease renal blood flow, resulting in decreased renal clearance and increase serum lithium concentrations.
• Intervention: More frequent serum lithium concentration monitoring.
• Renin-Angiotensin System Antagonists Clinical Impact: Concomitant use increase steady-state serum lithium concentrations.
• Serotonergic Drugs Clinical Impact: Concomitant use can precipitate serotonin syndrome.
• Intervention: Monitor patients for signs and symptoms of serotonin syndrome, particularly during lithium initiation. If serotonin syndrome occurs, consider discontinuation of lithium and/or concomitant serotonergic drugs.
• Nitroimidazole Antibiotics Clinical Impact: Concomitant use may increase serum lithium concentrations due to reduced renal clearance. Acetazolamide, Urea, Xanthine Preparations, Alkalinizing Agents Clinical Impact: Concomitant use can lower serum lithium concentrations by increasing urinary lithium excretion. Monitor patients for signs or symptoms of hypothyroidism. Reports of neurotoxic reactions in patients treated with both lithium and an antipsychotic, ranging from extrapyramidal symptoms to neuroleptic malignant syndrome, as well as reports of a encephalopathic syndrome in few patients treated with concomitant therapy.

• Pregnancy Risk Summary: Lithium may cause harm when administered to a pregnant woman. Early voluntary reports to international birth registries suggested an increase in cardiovascular malformations, especially for Ebstein's anomaly, with first trimester use of lithium. Subsequent case-control and cohort studies indicate that the increased risk for cardiac malformations is likely to be small; however, the data are insufficient to establish a drug-associated risk. There are concerns for maternal and/or neonatal lithium toxicity during late pregnancy and the postpartum period. Published animal developmental and toxicity studies in mice and rats report an increased incidence of fetal mortality, decreased fetal weight, increased fetal skeletal abnormalities, and cleft palate (mouse fetuses only) with oral doses of lithium that produced serum concentrations similar to the human therapeutic range. Other published animal studies report adverse effects on embryonic implantation in rats after lithium administration. Advise pregnant women of the potential risk to a fetus. The background risk of major birth defects and miscarriage for the indicated population(s) is unknown. In the U.S. general population, the estimated background risk of major birth defects and miscarriage in clinically recognized pregnancies is respectively.
• Clinical Considerations: Dose Adjustments During Pregnancy and the Postpartum Period: If the decision is made to continue lithium treatment during pregnancy, serum lithium concentrations should be monitored and the dosage adjusted during pregnancy. Two to three days prior to delivery, lithium dosage should be decreased or discontinued to reduce the risk of maternal and/or neonatal toxicity. Lithium may be restarted in the post-partum period at preconception doses in medically stable patients as long as serum lithium levels are closely monitored.
• Fetal/Neonatal Adverse Reactions: Lithium toxicity may occur in neonates who were exposed to lithium in late pregnancy. A floppy baby syndrome including neurological, cardiac, and hepatic abnormalities that are similar to those seen with lithium toxicity in adults have been observed. Symptoms include hypotonia, respiratory distress syndrome, cyanosis, lethargy, feeding difficulties, depressed neonatal reflexes, neonatal depression, apnea, and bradycardia. Monitor neonates and provide supportive care until lithium is excreted and toxic signs disappear, which may take up to 14 days. Consider fetal echocardiography between 16 and 20 weeks gestation in a woman with first trimester lithium exposure because of the potential increased risk of cardiac malformations.

Pediatric Use The safety and effectiveness of lithium for monotherapy treatment of acute manic or mixed episodes of bipolar I disorder and maintenance monotherapy of bipolar I disorder in pediatric patients ages 7 to 17 years of age have been established in an acute-phase clinical trial of 8 weeks in duration followed by a 28-week randomized withdrawal phase. The safety and effectiveness of lithium has not been established in pediatric patients less than 7 years of age with bipolar I disorder.

Lithium is contraindicated in patients with known hypersensitivity to any inactive ingredient in the lithium citrate products. Known hypersensitivity to any inactive ingredient in the drug product.

The toxic concentrations for lithium (≥1.5 mEq/L) are close to the therapeutic concentrations. At lithium concentrations greater than 3 mEq/L, patients may progress to seizures, coma, and irreversible brain damage. Treatment: For current information on the management of poisoning or overdosage, contact the National Poison Control Center at 1 -800-222-1222 or www.poison.org No specific antidote for lithium poisoning is known.

Mild symptoms of lithium toxicity can usually be treated by reduction in dose or cessation of the drug. In severe cases of lithium poisoning, the goal of treatment is elimination of this ion from the patient. Administration of gastric lavage should be performed, but use of activated charcoal is not recommended as it does not significantly absorb lithium ions.

Hemodialysis is the treatment of choice as it is an effective and rapid means of removing lithium in patients with severe toxicity. As an alternative option, urea, mannitol and aminophylline can induce a significant increase in lithium excretion. Appropriate supportive care for the patient should be undertaken.

Patients with impaired consciousness should have their airway protected and it is critical to correct any volume depletion or electrolyte imbalance. Patients should be monitored to prevent hypernatremia while receiving normal saline and careful regulation of kidney function is of utmost importance. Serum lithium concentrations should be closely monitored as there may be a rebound in serum lithium concentrations as a result of delayed diffusion from the body tissues.

Likewise, during the late recovery phase, lithium should be re-administered with caution taking into account the possible release of significant lithium stores in body tissues.