chlortalidone: prescribing and clinical use
Focused clinical detail for use alongside current product information, local policy and patient-specific assessment.
chlortalidone: clinical details
Prescribing considerations
- Use particular caution in older people and in hepatic or renal impairment because fluid and electrolyte disturbances may have greater consequences.
- Assess volume status and concurrent medicines that alter electrolytes, renal function or blood pressure.
- Nephrotic-syndrome oedema requires close supervision without baseline potassium or volume depletion.
Contraindications and cautions
- Hypersensitivity to chlortalidone, product excipients or other sulfonamide derivatives
- Anuria or severe renal or hepatic failure
- Refractory hypokalaemia, hyponatraemia or hypercalcaemia
- Symptomatic hyperuricaemia, including gout or uric-acid stones
- Hypertension during pregnancy
- Untreated Addison's disease
- Concomitant lithium treatment
Monitoring
- Blood pressure and clinical volume status
- Serum sodium, potassium, magnesium and calcium
- Kidney function
- Blood glucose in people with diabetes or metabolic risk
- Uric acid where gout or uric-acid stones are relevant
- Symptoms of acute visual disturbance
Clinical pharmacology
Chlortalidone inhibits the sodium-chloride cotransporter in the distal renal tubule. It accumulates in erythrocytes through carbonic-anhydrase binding, contributing to slow elimination and prolonged action. Most absorbed chlortalidone is eliminated unchanged, principally through the kidneys.
Formulation and product differences
- The selected product is a white, circular, convex, unscored tablet.
- It contains lactose monohydrate and is unsuitable for certain rare hereditary disorders affecting lactose or galactose handling.
- It is supplied in blister packaging.
chlortalidone preparations and strengths
Tablet
Route: Oral
Strengths: 12.5 mg, 50 mg
chlortalidone interactions
Important interactions include:
Lithium
Chlortalidone reduces lithium clearance and can rapidly raise lithium concentrations. Concomitant use is contraindicated for the selected product.
Other blood-pressure-lowering medicines
Blood-pressure lowering may be increased, causing dizziness or hypotension.
NSAIDs, such as ibuprofen or indometacin
They may weaken its effects and worsen kidney function in susceptible people.
Digoxin and other digitalis medicines
Low potassium or magnesium can increase the risk of digitalis-related arrhythmias.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.