What are SGLT2 inhibitors, and how do they protect the kidneys?
SGLT2 inhibitors are a class of tablet originally developed to lower blood sugar in type 2 diabetes. They work on the kidney, reducing the amount of glucose and sodium reabsorbed from urine, which lowers the pressure inside the kidney filters. The Agency for Care Effectiveness, which was set up by the Ministry of Health, states that for patients with chronic kidney disease the improvement in kidney and heart outcomes is independent of the blood-sugar-lowering effect — which is why they are used in kidney disease whether or not you have diabetes.
How much difference do these kidney drugs actually make?
In its 2023 clinical guidance on chronic kidney disease, the Agency for Care Effectiveness reports that SGLT2 inhibitors, compared with placebo, produced a 28 to 39 per cent reduction in composite kidney outcomes — a measure combining doubling of creatinine, worsening kidney function, onset of kidney failure, and death from kidney or cardiovascular causes — in patients with chronic kidney disease with or without diabetes. ACE inhibitors and ARBs are described as the mainstay treatment where there is albuminuria, for their effect in reducing both major cardiovascular events and kidney failure. These are trial averages, not a promise for any one person.
Can these drugs help me avoid dialysis?
They can slow the decline, and slowing the decline is what pushes dialysis further away. The Agency for Care Effectiveness frames the goal of treatment as delaying progression and reducing cardiovascular complications rather than curing the disease. How much time that buys any individual varies widely, and no one can put a number on it for you in advance. What is clear from the guidance is that starting earlier matters.
Do I need to have diabetes to be prescribed an SGLT2 inhibitor?
No. They were first marketed as diabetes medicines, but the Agency for Care Effectiveness states that the kidney benefits were seen in patients with and without diabetes, and recommends adding an SGLT2 inhibitor for patients with chronic kidney disease and persistent albuminuria regardless of diabetes status. What matters is your kidney function and whether protein is leaking into your urine.
Which medicine comes first?
There is a recommended order. The Agency for Care Effectiveness advises starting an ACE inhibitor or ARB for patients with chronic kidney disease and albuminuria, titrated up to the maximum dose you tolerate, and adding an SGLT2 inhibitor if albuminuria persists. It also advises against combining an ACE inhibitor with an ARB, because the evidence of benefit is limited and the risk of low blood pressure and high potassium goes up.
Are kidney protection drugs subsidised in Singapore?
Several are. The Agency for Care Effectiveness dosing tables mark which ACE inhibitors and ARBs appear on the government subsidy list, and SGLT2 inhibitors have been added to national subsidy. What you pay depends on your own circumstances, so ask us when you book, including about CHAS and Healthier SG.
How do I know if my kidneys are failing? I feel fine.
You very likely would feel fine — that is the problem. Early chronic kidney disease has almost no symptoms. It is picked up by testing, not by how you feel: a blood test for eGFR, which estimates how well the kidneys filter, and a urine albumin-to-creatinine ratio, which detects protein leaking into the urine. The Agency for Care Effectiveness recommends both at least annually for everyone with chronic kidney disease. Both are simple, and we can do them here.
Who should be screened for chronic kidney disease?
Testing is aimed at people whose risk is already raised — those with diabetes, high blood pressure, obesity or cardiovascular disease, and those with a family history of kidney failure. Diabetes and high blood pressure are the two conditions most strongly associated with kidney damage in Singapore. If any of those apply to you, ask us about testing at your next visit.
Is it too late if my kidney disease is already advanced?
No. But there is a reason to act early that many people find surprising: the Agency for Care Effectiveness notes that in Singapore, people detected at the earliest stages were losing kidney function faster each year than those at later stages — which is precisely why its guidance concentrates on early-stage management. Advanced disease still warrants treatment, and often shared care with a kidney specialist.
My kidney function dropped slightly after starting the medicine. Should I stop?
Usually not, and it is worth knowing the numbers before it happens. For SGLT2 inhibitors, the Agency for Care Effectiveness states that an acute dip may occur 2 to 4 weeks after starting, and that a rise in creatinine of up to 30 per cent is not associated with long-term loss of kidney function and is not a reason to discontinue. For ACE inhibitors and ARBs, treatment need not be stopped if the fall in eGFR is under 25 per cent from baseline. Above those thresholds, it does need review — which is why we recheck your bloods after starting.
What are the side effects of SGLT2 inhibitors?
The Agency for Care Effectiveness names two in particular: an increased risk of recurrent urinary and genitourinary infections, and an increased risk of euglycaemic ketoacidosis — a serious problem that can occur even when blood sugar readings look normal. Good hygiene and adequate fluids reduce the infection risk. Seek medical attention promptly if you feel unwell with nausea, vomiting, abdominal pain or rapid breathing.
Should I stop my kidney medicine if I am unwell?
Sometimes, yes — and this is the single most useful thing to know. The Agency for Care Effectiveness lists medicines that should be stopped during acute illness and restarted on recovery, under the memory aid SADMANS: sulfonylureas and other secretagogues, ACE inhibitors, diuretics and direct renin inhibitors, metformin, ARBs, NSAIDs, and SGLT2 inhibitors. If you are vomiting, have diarrhoea, cannot keep fluids down, are fasting for a procedure or are seriously unwell, contact us. Outside those situations, do not stop them on your own.
Can I take these if I am pregnant or planning a pregnancy?
ACE inhibitors and ARBs must not be taken in pregnancy — they can harm the developing baby, and they are normally changed to something else before conception rather than after a positive test. Tell us early if you are planning a pregnancy so we can plan the switch. SGLT2 inhibitors are also not used in pregnancy.
Do the medicines mean I can stop worrying about diet and lifestyle?
No. The Agency for Care Effectiveness treats lifestyle as a complement to medication, not an optional extra, and names physical activity, a healthy diet and stopping smoking. On salt it is specific: the general-population recommendation of less than 2g of sodium a day — under a teaspoon of salt — has been adopted for kidney patients in recent guidelines. It also cautions against drastic restriction. Blood pressure and blood sugar targets matter too, with under 130/80 mmHg and an HbA1c of 7 per cent or below used for most patients with early-stage disease.
Are there medicines I should avoid?
Yes, and some are sold over the counter. The Agency for Care Effectiveness advises reviewing home medications and educating patients about over-the-counter products that may be toxic to the kidneys, singling out NSAID painkillers, including combination products, and some supplements and herbal products. It also notes that more than two-thirds of prescription medicines are cleared by the kidneys and may need dose adjustment when kidney function falls. Bring everything you take to your appointment.
How often should my kidneys be checked once I am on treatment?
It depends on your stage. The Agency for Care Effectiveness suggests roughly every 6 to 12 months for the mildest combinations of filtering rate and protein leak, every 3 to 6 months as those worsen, and every 1 to 4 months for the most severe early-stage category. eGFR and urine ACR are recommended at least annually for everyone with chronic kidney disease.
Do I need to see a kidney specialist, or can a GP manage this?
Much of it belongs in primary care — the Agency for Care Effectiveness guidance is explicitly written for healthcare professionals including those in primary care. But it also lists situations calling for shared or specialist care: later-stage disease, a suspected specific cause such as glomerulonephritis, nephrotic syndrome, the need for a biopsy, rapidly progressive disease, acute kidney injury, anaemia related to kidney disease, resistant high blood pressure, persistent high potassium, or bone and calcium problems. We will tell you plainly which side of that line you are on.
