LITHIUM CARBONATE

(li'thee-um)

Eskalith, Eskalith CR, Lithane, Lithobid, Lithonate, Lithotabs
LITHIUM CITRATE
Cibalith-S
Classifications: psychotherapeutic agent; mood stabilizer;
Therapeutic: mood stabilizer; antimanic and antidepressant
Pregnancy Category: C first trimester; D second and third trimester

Availability

Lithium Carbonate: 150 mg, 300 mg, 600 mg capsules; 300 mg, 450 mg sustained release tablets

Lithium Citrate: 300 mg/5 mL syrup

Action

The lithium ion behaves in the body much like the sodium ion; but its exact mechanism of action is unclear. Competes with various physiologically important cations: Na⁺, K⁺, Ca⁺⁺, Mg⁺⁺; therefore, it affects cell membranes, body water, and neurotransmitters. At the synapse, it accelerates catecholamine destruction, inhibits the release of neurotransmitters and decreases sensitivity of postsynaptic receptors.

Therapeutic Effect

Inhibits neurotransmitters; decreases over-activity of receptors involved in stimulating manic states. Effective response evidenced by changed facial affect, improved posture, assumption of self-care, improved ability to concentrate, improved sleep pattern.

Uses

Control and prophylaxis of acute mania and the acute manic phase of mixed bipolar disorder.

Unlabeled Uses

Acute and recurrent depression (unipolar affective disorder), schizophrenic disorders, disorders of impulse control, alcohol dependence, antineoplastic drug-induced neutropenia, aplastic anemia, SIADH, cyclic neutropenia.

Contraindications

History of ACE inhibitor induced angioedema; significant cardiovascular or kidney disease, brain damage, severe debilitation, dehydration or sodium depletion; patients on low-salt diet or receiving diuretics; pregnancy (category C in first trimester, category D in second and third trimester), lactation, children <12 y.

Cautious Use

Older adults; thyroid disease; epilepsy; concomitant use with haloperidol and other antipsychotics; cardiac disease, cardiac arrhythmias, dehydration, diarrhea; older adults; fever, hyponatremia, hypothyroidism, concurrent infection; leukemia; mental status changes, organic brain syndrome, parkinsonism; psoriasis; renal disease, renal impairment; seizure disorder, sick sinus syndrome, sodium restriction, suicidal ideation, thyroid disease, urinary retention; diabetes mellitus; severe infections; urinary retention.

Route & Dosage

Mania
Adult: PO Loading Dose 600 mg t.i.d. or 900 mg sustained-release b.i.d. or 30 mL (48 mEq) of solution t.i.d. PO Maintenance Dose 300 mg t.i.d. or q.i.d. or 15–20 mL (24–32 mEq) solution in 2–4 divided doses (max: 2.4 g/d)
Child: PO 15–60 mg/kg/d in divided doses

Administration

Oral

Give with meals.
Ensure that sustained release tablets are not chewed or crushed; must be swallowed whole.
Protect from light and moisture.

Adverse Effects (≥1%)

CNS: Dizziness, headache, lethargy, drowsiness, fatigue, slurred speech, psychomotor retardation, giddiness, incontinence, restlessness, seizures, confusion, blackout spells, disorientation, recent memory loss, stupor, coma, EEG changes. CV: Arrhythmias, hypotension, vasculitis, peripheral circulatory collapse, ECG changes. Special Senses: Impaired vision, transient scotomas, tinnitus. Endocrine: Diffuse thyroid enlargement, hypothyroidism, nephrogenic diabetes insipidus, transient hyperglycemia, glycosuria, hyponatremia. GI: Nausea, vomiting, anorexia, abdominal pain, diarrhea, dry mouth, metallic taste. Musculoskeletal: Fine hand tremors, coarse tremors, choreoathetotic movements; fasciculations, clonic movements, incoordination including ataxia, muscle weakness, hyperreflexia, encephalopathic syndrome (weakness, lethargy, fever, tremors, confusion, extrapyramidal symptoms). Skin: Thought to be toxicity rather than allergy: Pruritus, maculopapular rash, hyperkeratosis, chronic folliculitis, transient acneiform papules (face, neck, intertriginous areas), anesthesia of skin, cutaneous ulcers, drying and thinning of hair, allergic vasculitis. Hematologic: Reversible leukocytosis (14,000 to 18,000/mm³). Urogenital: Albuminuria, oliguria, urinary incontinence, polyuria, polydipsia, increased uric acid excretion. Body as a Whole: Edema, weight gain (common) or loss, exacerbation of psoriasis; flu-like symptoms.

Interactions

Drug: Carbamazepine, haloperidol, phenothiazines increase risk of neurotoxicity, extrapyramidal effects, and tardive dyskinesias; diuretics, nsaids, methyldopa, probenecid, tetracyclines decrease renal clearance of lithium, increasing pharmacologic and toxic effects; theophyllines, urea, sodium bicarbonate, sodium or potassium citrate increase renal clearance of lithium, decreasing its pharmacologic effects.

Pharmacokinetics

Absorption: Readily absorbed from GI tract. Peak: 0.5–3 h carbonate; 15–60 min citrate. Distribution: Crosses blood–brain barrier and placenta; distributed into breast milk. Metabolism: Not metabolized. Elimination: 95% in urine, 1% in feces, 4–5% in sweat. Half-Life: 20–27 h.

Nursing Implications

Assessment & Drug Effects

Monitor response to drug. Usual lag of 1–2 wk precedes response to lithium therapy. Keep physician informed of progress.
Lab test: Periodic lithium levels (draw blood sample prior to next dose or 8–12 h after last dose); periodic thyroid function tests.
Monitor for S&S of lithium toxicity (e.g., vomiting, diarrhea, lack of coordination, drowsiness, muscular weakness, slurred speech when level is 1.5–2.0 mEq/L; ataxia, blurred vision, giddiness, tinnitus, muscle twitching, coarse tremors, polyuria when >2.0 mEq/L). Withhold one dose and call physician. Drug should not be stopped abruptly.
Monitor older adults carefully to prevent toxicity, which may occur at serum levels ordinarily tolerated by other patients.
Be alert to and report symptoms of hypothyroidism (see Appendix F).
Weigh patient daily; check ankles, tibiae, and wrists for edema. Report changes in I&O ratio, sudden weight gain, or edema.
Report early signs of extrapyramidal reactions promptly to physician.

Patient & Family Education

Be alert to increased output of dilute urine and persistent thirst. Dose reduction may be indicated.
Contact physician if diarrhea or fever develops. Avoid practices that may encourage dehydration: hot environment, excessive caffeine beverages (diuresis).
Drink plenty of liquids (2–3 L/d) during stabilization period and at least 1–1? L/d during ongoing therapy.
Avoid self-prescribed low-salt regimen, self-dosing with antacids containing sodium, and high-sodium foods (e.g., prepared meats and diet soda).
Do not drive or engage in other potentially hazardous activities until response to drug is known. Lithium may impair both physical and mental ability.
Use effective contraceptive measures during lithium therapy. If therapy is continued during pregnancy, serum lithium levels must be closely monitored to prevent toxicity.

Common adverse effects in italic, life-threatening effects underlined; generic names in bold; classifications in SMALL CAPS; Canadian drug name; Prototype drug

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