hydrochlorothiazide + losartan: prescribing and clinical use
Focused clinical detail for use alongside current product information, local policy and patient-specific assessment.
hydrochlorothiazide + losartan: clinical details
Prescribing considerations
- This fixed combination is not intended as initial antihypertensive therapy; establish the suitability of both components.
- Correct intravascular volume or sodium depletion before initiation.
- Review renal or hepatic impairment, renal artery stenosis, heart failure, diabetes, gout, electrolyte disorders, previous angioedema, lupus and previous non-melanoma skin cancer.
- Counsel about sun and UV protection and reporting new or changing skin lesions.
- Consider clinical review during illness causing dehydration.
Contraindications and cautions
- Hypersensitivity to losartan, sulfonamide-derived substances or product excipients
- Therapy-resistant hypokalaemia, hypercalcaemia or hyponatraemia
- Symptomatic hyperuricaemia or gout
- Severe hepatic impairment, cholestasis or biliary obstruction
- Severe renal impairment or anuria
- Second or third trimester of pregnancy
- Aliskiren co-administration in patients with diabetes or qualifying renal impairment
- Previous hydrochlorothiazide-associated acute respiratory distress syndrome
Monitoring
- Blood pressure and symptoms of postural hypotension
- Renal function and volume status
- Potassium, sodium, calcium and other relevant electrolytes
- Glucose and uric acid where clinically relevant
- Lithium concentration, ECG or additional tests when interacting treatment requires them
- Skin examination for suspicious lesions; reconsider hydrochlorothiazide after previous non-melanoma skin cancer
Clinical pharmacology
Losartan selectively antagonises angiotensin II at AT1 receptors and has an active carboxylic-acid metabolite. Hydrochlorothiazide inhibits sodium and chloride reabsorption in the distal renal tubule. The combination produces additive antihypertensive activity.
Formulation and product differences
- The selected product is a white, circular, biconvex film-coated tablet marked “C” and “79”.
- It contains lactose monohydrate and should be swallowed whole.
- It may be supplied in PVC/PVDC blisters or an HDPE container; not every authorised pack size is necessarily marketed.
hydrochlorothiazide + losartan preparations and strengths
Tablet
Route: Oral
Strengths: 50 mg + 12.5 mg, 100 mg + 12.5 mg, 100 mg + 25 mg
hydrochlorothiazide + losartan interactions
Tell the prescriber or pharmacist about all medicines, supplements and salt substitutes. Important examples include:
Potassium supplements, potassium salt substitutes, potassium-sparing diuretics or trimethoprim
May increase blood potassium; combined use is generally inadvisable without clinical review and monitoring.
Lithium
May increase lithium toxicity risk, requiring avoidance or close monitoring.
NSAIDs such as ibuprofen
May weaken blood-pressure control and increase kidney impairment and potassium changes, especially during dehydration.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.