Lab value · SDMA
Cat SDMA levels, explained
SDMA is a newer kidney marker. Like creatinine, it is cleared by the kidneys, but it is less affected by muscle mass — useful for older, thinner cats.
What a higher sdma can mean
A higher SDMA suggests reduced kidney filtering. A single raised result is usually rechecked before drawing conclusions.
What a lower sdma can mean
A lower SDMA is generally reassuring and may reflect stable or improved kidney filtering.
Why it matters in kidney disease
- SDMA tends to rise earlier than creatinine as kidney filtering drops, so it can flag changes sooner.
- It is much less affected by muscle mass, which makes it useful in older or thin cats.
- IRIS suggests that an SDMA persistently above 14 µg/dL in a cat with normal creatinine may point to reduced kidney function, and that should be followed up.
- A single raised SDMA is usually repeated before conclusions are drawn.
IRIS reference bands
IRIS publishes reference bands for sdma in cats. A value in a band is not a diagnosis: these are reference ranges, not a stage. only your vet can stage ckd — in a cat that is clinically stable and well hydrated, using results from at least two occasions and the whole clinical picture.
Source: IRIS Staging of CKD (modified 2023) — iris-kidney.com; phosphate targets: 2026 iCatCare consensus guidelines.
What does my cat’s number mean?
- An SDMA of 12 µg/dL is in the range IRIS associates with Stage 1.
- An SDMA of 15 µg/dL is in the range IRIS associates with Stage 1. If it stays above 14 on repeat tests, IRIS suggests that can point to reduced kidney function even when creatinine is normal.
- An SDMA of 18 µg/dL is in the range IRIS associates with Stage 2.
- An SDMA of 20 µg/dL is in the range IRIS associates with Stage 2.
- An SDMA of 25 µg/dL is in the range IRIS associates with Stage 2.
- An SDMA of 30 µg/dL is in the range IRIS associates with Stage 3.
- An SDMA of 40 µg/dL is in the range IRIS associates with Stage 4.
Whatever the number, one result is a snapshot. Your vet will look at hydration, the trend over time and other tests together.
Questions to ask your vet
Ask your vet
- Do my cat’s SDMA and creatinine tell the same story?
- Should we repeat SDMA to confirm this result?
Decode your cat’s SDMA
Enter your cat’s values and get a plain-English summary, IRIS reference bars and questions for your vet.
Frequently asked questions
What is SDMA in a cat blood test?
SDMA is a newer kidney marker. Like creatinine, it is cleared by the kidneys, but it is less affected by muscle mass — useful for older, thinner cats.
What does a high sdma mean in cats?
A higher SDMA suggests reduced kidney filtering. A single raised result is usually rechecked before drawing conclusions.
What does a low sdma mean in cats?
A lower SDMA is generally reassuring and may reflect stable or improved kidney filtering.
What is a normal sdma level for a cat?
A typical feline reference interval is about Example only: 0 – 14 µg/dL. Use the range printed on your cat’s report — it differs between labs., but every lab sets its own range. The range printed on your cat’s report is the one to use.
What does an SDMA of 18 mean in a cat?
An SDMA of 18 µg/dL sits at the bottom of the range IRIS associates with Stage 2. It suggests kidney filtering may be reduced. Many vets will repeat the test, check creatinine and a urine sample, and look at the trend before drawing conclusions.
The KidneyPaw app
See every lab, decoded, and how the numbers change.
KidneyPaw decodes lab reports in plain English, looks up the phosphorus in any food, and keeps meds and fluids on track for the whole family. Free to start.