Lithium is a prescription pill that contains the active ingredients lithium carbonate and lithium citrate. It belongs to the mental health therapeutic class and is used primarily to manage mood disorders. In Hong Kong, lithium is regulated by the Department of Health’s Drug Office and is available in 300 mg tablets. Brand-name formulations such as Lithobid and Eskalith contain the same active components.
Lithium’s exact mood-stabilizing mechanism is not fully understood, but key actions include:
These actions help blunt the extreme highs (mania) and lows (depression) seen in bipolar disorder. Lithium is absorbed well from the gastrointestinal tract, reaches peak plasma concentrations within 2 - 4 hours, and has a half-life of approximately 24 hours, allowing once- or twice-daily dosing.
Lithium is the only medication approved by many regulatory agencies for the reduction of suicide risk in patients with mood disorders. In Hong Kong, its approved indications align with those of the United States FDA and the European EMA.
Off-label use requires medical supervision, individualized risk assessment, and ongoing monitoring for toxicity.
Absolute contraindications
Relative contraindications
Special populations
Patients should disclose all prescription drugs, over-the-counter medications, supplements, and herbal products before starting lithium.
Any new symptoms of tremor, polyuria, or cognitive changes should prompt an earlier laboratory review.
This article provides educational information about lithium and is not a substitute for professional medical advice. Treatment decisions, including use for unapproved indications, must be made under the guidance of a qualified healthcare provider. The content is intended for informational purposes and does not constitute medical recommendations. Always consult a physician before starting, stopping, or changing any medication regimen.
Carry the medication in its original labeled container, accompanied by a copy of the prescription and a doctor’s note stating the need for the drug. Keep the supply in your carry-on luggage to avoid temperature extremes and ensure easy access during security screening.
Lithium is not a controlled substance and does not appear on standard occupational or athletic drug-screen panels. However, disclosure to the testing authority is advisable if the test includes therapeutic drug monitoring.
Legitimate tablets are round, film-coated, and imprinted with “300 mg” and the manufacturer’s logo. Look for consistent color, clear imprint, and a dated expiration on the blister pack. If in doubt, compare with a pharmacy-provided sample or request verification.
Maintain a consistent sodium intake; abrupt reductions can raise lithium levels, while excessive salt can lower them. Avoid excessive caffeine and alcohol, as they may exacerbate dehydration and affect lithium clearance.
Both salts deliver elemental lithium, but lithium carbonate is the most common formulation worldwide. Lithium citrate is sometimes used in liquid preparations or in combination products; the therapeutic effect depends on total elemental lithium dose, not the salt type.
Lithium has a narrow therapeutic window; serum levels can change with renal function, hydration status, or interacting medications. Regular testing ensures the dose remains effective while avoiding toxicity.
Combination therapy (e.g., lithium plus valproate) is sometimes employed for refractory bipolar disorder but increases monitoring demands. Only a psychiatrist should decide on such regimens.
Severe tremor, confusion, slurred speech, ataxia, vomiting, diarrhea, or a rapid heart rate are warning signs. Seek emergency medical attention immediately if these symptoms appear.
Lithium can affect cardiac conduction, especially in high doses or in the presence of electrolyte imbalances. Patients with known cardiac arrhythmias should have baseline ECG evaluation and close monitoring.
For acute mania, improvement often begins within 5-7 days of reaching therapeutic serum levels. Maintenance benefits in preventing mood episodes may require several weeks of stable dosing.
