chlortalidone at a glance
Medicine class
Long-acting thiazide-like diuretic
Main roles
High blood pressure, stable chronic heart failure, specific oedema and diabetes insipidus
Monitoring
Blood pressure, kidney function and blood electrolytes may require checks
What is chlortalidone used for?
The selected product is licensed for:
Arterial hypertension
Stable mild-to-moderate chronic heart failure
Ascites caused by cirrhosis in stable patients under close supervision
Oedema caused by nephrotic syndrome
Diabetes insipidus
How does chlortalidone work?
Chlortalidone blocks sodium and chloride reabsorption in the distal kidney tubule. More sodium and water leave in urine, reducing excess fluid. Reduced resistance in blood vessels helps maintain its blood-pressure effect.
chlortalidone preparations and strengths
Tablet
Route: Oral
Strengths: 12.5 mg, 50 mg
How to take chlortalidone
The tablet is taken by mouth. The selected tablet is unscored and contains lactose.
Swallow with water.
If dizziness occurs, avoid driving or using machinery until it has passed.
chlortalidone side effects
Common or expected effects
- Low potassium, sodium or magnesium
- Raised uric acid, blood glucose or blood lipids
- Dizziness or a fall in blood pressure on standing
- Skin rash or hives
- Reduced appetite or mild stomach upset
- Erectile difficulties
Get urgent medical advice
- Sudden eye pain, blurred vision or loss of vision
- Severe breathing difficulty or signs of a serious allergic reaction
- Irregular heartbeat, fainting, severe weakness or muscle spasms
- Yellow skin or eyes
- Severe upper abdominal pain
- Unusual infections, fever, mouth ulcers, bleeding or bruising
chlortalidone in pregnancy
Chlortalidone is contraindicated for hypertension during pregnancy in the selected product information. Diuretics are generally avoided for pregnancy-related hypertension or oedema, although a specialist may consider one for a serious maternal heart or kidney condition. Discuss pregnancy or pregnancy plans with the prescriber rather than stopping treatment independently.
chlortalidone while breastfeeding
Chlortalidone passes into breast milk, and the selected product information advises against breastfeeding during treatment. A prescriber or specialist breastfeeding service should review alternatives and the clinical need for treatment.
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.
Common questions about chlortalidone
Answers are fully visible for fast scanning and source review.
Does chlortalidone make you pass more urine?
Yes. It increases urinary loss of sodium and water.
Can chlortalidone cause dizziness?
Yes. Dizziness and a fall in blood pressure on standing are recognised effects. Rise slowly and do not drive or use machinery while affected.
Do I need blood tests?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.