Related guidance: Hypertension in adults: diagnosis and management NICE guideline (NG136 August 2019, updated March 2022)

Chronic heart failure in adults: diagnosis and management NICE guideline (NG106 September 2018)

See NHS Somerset formulary Useful links for NHS Somerset sick day rules.

Therapeutic AreaFormulary ChoicesCost for 28
(unless otherwise stated)
Rationale for decision / comments
Loop diureticsFurosemide20mg tablets: £0.63
40mg tablets: £0.66
Furosemide is included in the formulary for use
Heart failure: to provide relief of symptoms. Patients’ who do not respond to 80mg/day will require further specialist advice.
Hypertension: For treatment of resistant hypertension at Step 4 where BP remains sub-optimally controlled despite standard therapies.
Potassium-sparing diuretics (aldosterone antagonists)Spironolactone25mg tablets: £1.37
50mg tablets: £2.25
Spironolactone is included in the formulary for:
Heart failure: second line for specialist initiation in heart failure due to left ventricular systolic dysfunction. Closely monitor potassium and creatinine levels, and eGFR.

Hypertension: For treatment of resistant hypertension at step 4 if blood potassium is ≤ 4.5mmol/l

Monitor electrolytes—discontinue if hyperkalaemia occurs (in severe heart failure monitor potassium and creatinine 1 week after initiation and after any dose increase, monthly for first 3 months, then every 3 months for 1 year, and then every 6 months).

MHRA alert (Feb 2016) includes the following reminder:
•Concomitant use of spironolactone with ACEi or ARB is not routinely recommended because of the risks of severe hyperkalaemia, particularly in patients with marked renal impairment
•Use the lowest effective doses of spironolactone and ACEi or ARB if coadministration is considered essential
•Regularly monitor serum potassium levels and renal function
•Interrupt or discontinue treatment in the event of hyperkalaemia

Eplerenone25mg tablets: £4.07
50mg tablets: £5.68
As an alternative to spironolactone, where sex hormone mediated adverse effects experienced when used, in addition to standard therapy, to reduce the risk of cardiovascular mortality and morbidity after recent myocardial infarction in stable patients with left ventricular dysfunction and clinical evidence of heart failure.
Thiazides and related diureticsIndapamide2.5mg tablets: £0.96
1.5mg MR tablets: £3.40 (30)
Hypertension: indapamide 2.5mg daily is considered the optimal dose for hypertension.
Low dose indapamide 1.5mg SR has been shown to control hypertension as effectively as 2.5mg (IR) with lower incidence of hypokalaemia.
Bendroflumethiazide2.5mg tablets: £0.66NB People treated with bendroflumethiazide whose blood pressure is stable & well controlled should continue on bendroflumethiazide
Heart failure: bendroflumethiazide may have a limited role in mild heart failure or where patients are intolerant of loop diuretics.
as Xaqua®
5mg tablets: £110.00 (20)
NHS Somerset classify Metolazone as Amber as per Traffic light guidance.
Prescribers and dispensers should use caution if switching patients between different metolazone preparations as the rate and extent of absorption of metolazone are formulation dependent. This can impact the bioavailability of the product. Follow good practice in prescribing medicines by considering the licensed formulation (Xaqua) in preference to unlicensed imported metolazone preparations in new patients. The product information for Xaqua has been updated to clarify that references to comparative bioavailability with other metolazone products relate specifically to Metenix and not to any other metolazone preparations. See MHRA Drug Safety Update (January 2023) for Xaqua (metolazone) 5mg tablets: exercise caution when switching patients between metolazone preparations.