New moiety: Candesartan + Hydrochlorothiazide
The NHS BSA has added Candesartan + Hydrochlorothiazide to the dm+d dictionary (version 5.0.0). This is a fixed-dose combination of an angiotensin II receptor antagonist and a thiazide diuretic, used to manage chronic hypertension in patients already stabilised on both components.
What is it used for?
Candesartan + Hydrochlorothiazide is prescribed for hypertension maintenance only. Common doses are 16 mg/12.5 mg or 32 mg/12.5 mg once daily. It is not an acute-event medication and should never be initiated in the field.
Event medicine relevance
You may encounter patients on this combination at medical events, particularly older attendees or those with chronic conditions. Key points:
- Patients should continue their regular dose unless acute illness or significant fluid loss occurs.
- Dehydration is a major risk at events — it increases the risk of symptomatic hypotension and acute kidney injury.
- If a patient becomes hypotensive, develops signs of acute kidney injury, or reports severe dizziness, stop the dose and escalate to hospital.
- Monitor for signs of volume depletion, especially in hot conditions or during prolonged exertion.
Key cautions and interactions
Cautions: Renal impairment, hepatic impairment, diabetes, gout history, systemic lupus erythematosus, volume depletion, and elderly patients (increased hypotension sensitivity).
Important interactions:
- NSAIDs — increased risk of renal impairment and hyperkalaemia
- ACE inhibitors — avoid concurrent use (hyperkalaemia risk)
- Potassium-sparing diuretics and potassium supplements — hyperkalaemia
- Lithium — reduced clearance; levels must be monitored
- Alcohol — additive hypotensive effect
Common side effects: Dizziness, headache, fatigue, cough, hyperglycaemia, hypokalaemia, hyperuricaemia.
Serious side effects to watch for: Symptomatic hypotension, acute kidney injury, angioedema, syncope, severe electrolyte disturbance.
References
BNF: Candesartan with hydrochlorothiazide