Lithium carbonate (IR/SR)

Alkali metal cation·Psychiatry - Mood Stabilisers

Bipolar I disorder (mania and maintenance), prevention of recurrent depression

PBSMOOD STABQuilonum SR (450 mg), Lithicarb (250 mg)250 mg tabletS4+1

Target Range

0.6–0.8 mmol/L

Half-life

24 h

Toxicity Risk

HIGH

Renal Adj.

MANDATORY

Rapid Summary

Overview

The absolute gold standard mood stabiliser. Dramatically reduces suicide rates in Bipolar Disorder. Incredibly narrow therapeutic index. Treated like a toxic heavy metal by the kidneys.

Maximum Dose

Titrated strictly via Therapeutic Drug Monitoring (TDM).

Clinical Focus

The kidneys cannot tell the difference between Lithium and Sodium. If a patient gets dehydrated (low sodium), the kidney will hoard Lithium, causing fatal toxicity in days.

Bottom Line

Lithium carbonate (IR/SR) is the gold-standard mood stabiliser for bipolar disorder with unique anti-suicidal properties, but has an extremely narrow therapeutic index requiring regular serum level, renal, and thyroid monitoring.

Formulation & Access

Brand Names

Quilonum SR (450 mg), Lithicarb (250 mg)

Oral Routes

Tablets IR (250 mg). Tablets SR (450 mg).

Prescribing & PBS

Unrestricted General Benefit (S4).

Indications & Use

Primary

PBSTGA

Bipolar I disorder (mania and maintenance), prevention of recurrent depression.

Clinical Place

Unmatched efficacy in true Bipolar disorder. The only psychiatric drug definitively proven to prevent suicide.

Quick reference

Class & Role

Alkali metal cation — The absolute gold standard mood stabiliser.

Route / Formulation

Tablets IR (250 mg). Tablets SR (450 mg). (Quilonum SR (450 mg), Lithicarb (250 mg))

Usual Dose & Max

Start PO 250 mg (IR) BD or 450 mg (SR) OD. Titrate carefully over weeks. Target blood level: 0.6 - 0.8 mmol/L (Maintenance) or up to 1.0 mmol/L (Acute Mania). Titrated strictly via Therapeutic Drug Monitoring (TDM).

Key Indication Doses

Bipolar Maintenance: Start PO 250 mg (IR) BD or 450 mg (SR) OD. Titrate carefully over weeks. Target blood level: 0.6 - 0.8 mmol/L (Maintenance) or up to 1.0 mmol/L (Acute Mania). Renal Impairment: Excreted 100% by the kidneys. Avoid entirely in severe renal failure. If eGFR drops, dose MUST drop.

Best Uses

Avoid / Cautions

Severe renal impairment, uncorrected sodium depletion/dehydration. Pregnancy Category D. Causes Ebstein's anomaly (severe fetal cardiac defect).

Key Risks

Neurological (Toxicity): Coarse tremor, ataxia, confusion, seizures, coma, permanent cerebellar damage (SILENT syndrome). Renal: Nephrogenic Diabetes Insipidus (polyuria, extreme thirst), chronic interstitial nephritis leading to permanent CKD. Endocrine: Hypothyroidism (competes with iodine in the thyroid), hyperparathyroidism/hypercalcemia. Gastrointestinal: Nausea, diarrhea (often early signs of toxicity).

Key Interactions

NSAIDs, ACEi/ARBs, and Thiazide Diuretics. All three of these completely destroy the kidney's ability to excrete Lithium, doubling blood levels and causing lethal toxicity. DO NOT prescribe Ibuprofen, Perindopril, or HCTZ to a Lithium patient.

Monitoring

TDM (Serum Lithium Level) checked strictly 12 HOURS post-dose. Must wait 5-7 days after a dose change to check. Target 0.6-0.8 mmol/L. 6-monthly U&E, eGFR, TFTs, and Calcium levels for life. 'Sick Day Rules': If the patient gets gastro/vomiting, they must stop Lithium immediately and go to hospital. Dehydration = Toxicity.

Clinical Pearl

A patient on stable Lithium takes Nurofen (Ibuprofen) for a sprained ankle for 3 days. The NSAID restricts renal blood flow. The Lithium spikes to 2.5 mmol/L. The patient seizes and dies. Always check the medication list.

Access

Quilonum SR (450 mg), Lithicarb (250 mg)250 mg tablet

Brand: Quilonum SR (450 mg), Lithicarb (250 mg)
Formulation: Tablets IR (250 mg)