Which medications are contraindicated in patients with diabetic nephropathy, and what alternatives should I consider?

In patients with diabetic nephropathy, certain medications and substances are contraindicated or should be used with caution:

• Salt substitutes containing potassium chloride should not be used by people with diabetes, kidney disease, or those taking angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) ¹,². Instead, advise salt reduction in these groups ¹,².
• Indiscriminate chronic use of over-the-counter (OTC) Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) is associated with a higher risk of kidney failure and should be discouraged ¹,². It is recommended to review and limit the use of OTC medicines and dietary or herbal remedies that may be harmful for people with chronic kidney disease (CKD) ¹,².
• A combination of renin-angiotensin system antagonists (e.g., ACE inhibitors and ARBs together) should not be offered to adults with CKD ³.
• Renin-angiotensin system antagonists should not be routinely offered to adults with CKD if their pretreatment serum potassium concentration is greater than 5.0 mmol/litre ³. If hyperkalaemia prevents their use, assess and treat any other factors that promote hyperkalaemia and recheck serum potassium concentration ³.
• ACE inhibitors and ARBs should not be used in pregnant or breastfeeding women or women planning pregnancy unless absolutely necessary, with potential risks and benefits discussed ⁴.

Alternative treatments and considerations for patients with diabetic nephropathy include:

• Angiotensin-converting enzyme (ACE) inhibitors or angiotensin-receptor blockers (ARBs) are offered to adults, children, and young people with CKD who have hypertension and an albumin-to-creatinine ratio (ACR) over 30 mg/mmol ³. For adults with CKD and diabetes (type 1 or type 2), offer an ARB or an ACE inhibitor if ACR is 3 mg/mmol or more, titrated to the highest licensed dose that the person can tolerate ³,⁵.
• Sodium–glucose cotransporter‑2 (SGLT‑2) inhibitors are recommended for adults with CKD and type 2 diabetes if they have an estimated glomerular filtration rate (eGFR) of 20 ml/min per 1.73 m² or more ¹,². They are also offered in addition to an ARB or ACE inhibitor if ACR is over 30 mg/mmol and the person meets marketing authorisation criteria ⁵.
• Finerenone is an option for treating stage 3 and 4 CKD (with albuminuria) associated with type 2 diabetes in adults, only if it is an add-on to optimised standard care (including highest tolerated licensed doses of ACE inhibitors or ARBs, and SGLT-2 inhibitors unless unsuitable) and the person has an eGFR of 25 ml/min/1.73 m² or more ¹,².
• Statin treatment is recommended for all people with CKD ¹,². For people aged 18-49 years, statins are recommended if they have diabetes mellitus, known coronary disease, prior ischemic stroke, or an estimated 10-year incidence of coronary death or non-fatal myocardial infarction over 10% ¹,².
• Lifestyle measures such as stopping smoking and drinking alcohol in moderation should be advised ¹,².
• Provide education and information tailored to the severity and cause of CKD, associated complications, and risk of progression ¹,².