Thiazide diuretic
Hydrochlorothiazide
Adult dose
Dose: 12.5–50mg OD (mostly used as a fixed-dose component in UK)
Route: PO
Frequency: OD
Clinical pearls
- Often combined with ARB/ACEi; chlortalidone or indapamide preferred per NICE NG136 in UK
- MHRA: non-melanoma skin cancer risk — sun protection
Contraindications
- Severe renal/hepatic impairment
- Refractory hyponatraemia/hypokalaemia
- Symptomatic hyperuricaemia
- Pregnancy/breastfeeding
Side effects
- Hypokalaemia
- Hyponatraemia
- Hyperuricaemia
- Hyperglycaemia
- Photosensitivity
- Skin cancer risk (MHRA — recently associated with non-melanoma skin cancer)
Interactions
- NSAIDs (reduce effect)
- Lithium (toxicity)
- ACEi/ARB (additive hypotension)
- Other K+-lowering drugs
Monitoring
- U&E
- Glucose
- Skin checks
Reference: BNF; NICE NG136; MHRA Drug Safety Update; https://bnf.nice.org.uk/drugs/hydrochlorothiazide/. Verify against your local formulary and the latest BNF before prescribing.
Related
Curated clinical cross-links plus same-class fallbacks.
Pathways
- Acute Heart Failure · ESC 2021 Heart Failure Guidelines; NICE NG106
- NSTEMI / Unstable Angina · ESC 2020 NSTEMI Guidelines; NICE NG185
- New-Onset Atrial Fibrillation · ESC 2020 AF Guidelines; NICE NG196
- Hypertensive Emergency · ESC/ESH 2018 Hypertension Guidelines; NICE NG136
- Bradycardia Management · Resuscitation Council UK ABCDE; ESC 2021 Pacing Guidelines
- Ventricular Tachycardia / Fibrillation · Resuscitation Council UK ACLS; ESC 2022 Ventricular Arrhythmia Guidelines