Lithobid - Lithium Carbonate tablet, Film Coated, Extended Release prescribing information
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 (see DOSAGE AND ADMINISTRATION ).
DOSAGE AND ADMINISTRATION
Acute Mania
Optimal patient response can usually be established with 1800 mg/day in the following dosages:
| 1 Can also be administered on 600 mg TID recommended dosing interval. | |||
ACUTE MANIA | |||
Morning | Afternoon | Nighttime | |
LITHOBID ® Extended-Release Tablets 1 | 3 tabs (900 mg) | 3 tabs (900 mg) | |
Such doses will normally produce an effective serum lithium concentration ranging between 1.0 and 1.5 mEq/L. Dosage must be individualized according to serum concentrations and clinical response. Regular monitoring of the patient's clinical state and of serum lithium concentrations is necessary. Serum concentrations should be determined twice per week during the acute phase, and until the serum concentrations and clinical condition of the patient have been stabilized.
Long-Term Control
Desirable serum lithium concentrations are 0.6 to 1.2 mEq/L which can usually be achieved with 900 to 1200 mg/day. Dosage will vary from one individual to another, but generally the following dosages will maintain this concentration:
| 1 Can be administered on TID recommended dosing interval up to 1200 mg/day. | |||||||
LONG-TERM CONTROL | |||||||
Morning | Afternoon | Nighttime | |||||
LITHOBID ® Extended-Release Tablets 1 | 2 tabs (600 mg) | 2 tabs (600 mg) | |||||
Serum lithium concentrations in uncomplicated cases receiving maintenance therapy during remission should be monitored at least every two months. Patients abnormally sensitive to lithium may exhibit toxic signs at serum concentrations of 1.0 to 1.5 mEq/L. Geriatric patients often respond to reduced dosage, and may exhibit signs of toxicity at serum concentrations ordinarily tolerated by other patients. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.
Important Considerations
- Blood samples for serum lithium determinations should be drawn immediately prior to the next dose when lithium concentrations are relatively stable (i.e., 8 to 12 hours after previous dose). Total reliance must not be placed on serum concentrations alone. Accurate patient evaluation requires both clinical and laboratory analysis.
- LITHOBID ® Extended-Release Tablets must be swallowed whole and never chewed or crushed.
ADVERSE REACTIONS
The occurrence and severity of adverse reactions are generally directly related to serum lithium concentrations and to individual patient sensitivity to lithium. They generally occur more frequently and with greater severity at higher concentrations.
Adverse reactions may be encountered at serum lithium concentrations below 1.5 mEq/L. Mild to moderate adverse reactions may occur at concentrations from 1.5 to 2.5 mEq/L, and moderate to severe reactions may be seen at concentrations from 2.0 mEq/L and above.
Fine hand tremor, polyuria, and mild thirst may occur during initial therapy for the acute manic phase and may persist throughout treatment. Transient and mild nausea and general discomfort may also appear during the first few days of lithium administration.
These side effects usually subside with continued treatment or with a temporary reduction or cessation of dosage. If persistent, a cessation of lithium therapy may be required. Diarrhea, vomiting, drowsiness, muscular weakness, and lack of coordination may be early signs of lithium intoxication, and can occur at lithium concentrations below 2.0 mEq/L. At higher concentrations, giddiness, ataxia, blurred vision, tinnitus, and a large output of dilute urine may be seen. Serum lithium concentrations above 3.0 mEq/L may produce a complex clinical picture involving multiple organs and organ systems. Serum lithium concentrations should not be permitted to exceed 2.0 mEq/L during the acute treatment phase.
The following reactions have been reported and appear to be related to serum lithium concentrations, including concentrations within the therapeutic range:
Central Nervous System: tremor, muscle hyperirritability (fasciculations, twitching, clonic movements of whole limbs), hypertonicity, ataxia, choreoathetotic movements, hyperactive deep tendon reflex, 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. Cardiovascular: cardiac arrhythmia, hypotension, peripheral circulatory collapse, bradycardia, sinus node dysfunction with severe bradycardia (which may result in syncope), Unmasking of Brugada Syndrome (See WARNINGS and PATIENT COUNSELING INFORMATION ). 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, acne, chronic folliculitis, xerosis cutis, psoriasis or its 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. Thyroid Abnormalities: euthyroid goiter and/or hypothyroidism (including myxedema) accompanied by lower T3 and T4. 131 Iodine uptake may be elevated (see PRECAUTIONS ). Paradoxically, rare cases of hyperthyroidism have been reported. EEG Changes: diffuse slowing, widening of frequency spectrum, potentiation and disorganization of background rhythm. EKG Changes: reversible flattening, isoelectricity or inversion of T-waves. Miscellaneous: fatigue, lethargy, transient scotomata, exophthalmos, dehydration, weight loss, leucocytosis, headache, transient hyperglycemia, hypercalcemia, hyperparathyroidism, albuminuria, excessive weight gain, edematous swelling of ankles or wrists, metallic taste, dysgeusia/taste distortion, salty taste, thirst, swollen lips, tightness in chest, swollen and/or painful joints, fever, polyarthralgia, and dental caries.
Some reports of nephrogenic diabetes insipidus, hyperparathyroidism, and hypothyroidism which persist after lithium discontinuation have been received.
A few reports have been received of the development of painful discoloration of fingers and toes and coldness of the extremities within one day of starting lithium treatment. The mechanism through which these symptoms (resembling Raynaud's Syndrome) developed is not known. Recovery followed discontinuance.
DESCRIPTION
LITHOBID ® tablets contain lithium carbonate, a white odorless alkaline powder with molecular formula Li 2 CO 3 and molecular weight 73.89. Lithium is an element of the alkali-metal group with atomic number 3, atomic weight 6.94, and an emission line at 671 nm on the flame photometer.
Each peach-colored, film-coated, extended-release tablet contains 300 mg of lithium carbonate. This slowly dissolving film-coated tablet is designed to give lower serum lithium peak concentrations than obtained with conventional oral lithium dosage forms. Inactive ingredients consist of calcium stearate, carnauba wax, cellulose compounds, FD&C Blue No. 2 Aluminum Lake, FD&C Red No. 40 Aluminum Lake, FD&C Yellow No. 6 Aluminum Lake, povidone, propylene glycol, sodium chloride, sodium lauryl sulfate, sodium starch glycolate, sorbitol, and titanium dioxide. Product meets USP Drug Release Test 1.
HOW SUPPLIED
LITHOBID ® (Lithium Carbonate USP) Extended-Release Tablets, 300 mg, peach-colored imprinted “LITHOBID 300” NDC 62559-280-01 Bottle of 100