How to measure your cat’s blood sugar at home

When Manishka was diagnosed with diabetes in October 2025, I still had to learn how to measure your cat’s blood sugar at home: I knew how to read server graphs but had no idea how to get a drop of blood from a cat. At the clinic, blood sugar is often measured from a vein: the cat yowls, stress pushes glucose up — this is called stress hyperglycemia, and it is described in the ISFM (2015) and AAHA (2026) consensus statements — and you cannot build an insulin plan from a single reading like that.

At home it is much simpler: a lancet, a test strip, a glucose meter, a few seconds — closer to a human fingertip prick than to a blood draw. For the first week I spent more time preparing than the procedure itself took. Then my hand got used to it, and so did Manishka. Home readings matter not for their own sake: they show the vet how the treatment is working in the cat’s usual environment — that is covered in more detail in the overview article on diabetes in cats (/blog/diabetes-in-cats/). This one is about technique: where to take the sample, how to get the drop, and what to do when it doesn’t work. Which meter to buy is a separate topic: a glucose meter for cats.

Ear or Paw Pad

Two spots: the edge of the ear and the paw pad. According to the consensus statements, these sites are interchangeable — you can sample from either. In practice the ear is usually easier: the edge is thin, the vessels are close to the surface, the drop comes faster, the ear warms up more easily in your palms, and the cat is less likely to flinch when the strip is already in the meter. It is no accident that the iCatCare 2025 video shows the measurement taken from the ear, and AAHA 2026 lists the lateral edge of the ear pinna first among the sampling sites. The technique itself is described in the open guidelines: ISFM 2015, AAHA 2026, and that same iCatCare 2025 video.

The paw pad is thicker, the cat stands on it, and after a prick it may limp or lick the spot. It is a fallback for when the ear won’t give a drop or the cat won’t let you touch its head — and only if the vet has shown you how. Some cats actually give their paw more calmly — that’s temperament, not a mistake. Agree on the spot with the vet once and stick to it: readings can only be compared with each other if the method stays the same.

Step by Step

Before bringing the cat over, I lay everything out: meter on, strip in, fresh lancet, cotton pad within reach, log open. Otherwise she will be gone before I’m ready. I settle her where she sits anyway: the kitchen didn’t work — too bright and slippery — a blanket on the couch is better.

A cold ear barely bleeds. I hold the ear between my palms, rub the edge, sometimes press a warm — not hot — cloth against it for half a minute. The ear should turn pink, not red from rubbing. The prick goes on the inner side of the edge, close to the rim where the cartilage is thinnest: not toward the center and not toward the base, where it is thicker. A finger behind the ear keeps the edge from folding under — and keeps me from stabbing my own hand. The prick is short, perpendicular to the edge, no sawing. The lancet is single-use: a dulled needle on a second prick takes longer and hurts more.

Sometimes the drop appears on its own. If not, I gently massage the edge from the base toward the prick. You must not squeeze hard: AAHA 2026 explicitly warns that a drop should not be forced out by repeatedly squeezing the puncture site — such a drop will not be reliable. I bring the drop to the strip, not the strip to the ear: in most meters the blood is drawn in from the end of the strip, and the drop must cover the window completely. Not enough blood — I don’t smear a second drop over the first: new strip, start over. I press the site with a cotton pad, let the cat go, and write it down immediately: time, sugar, whether she ate, whether she got her shot. Without a record a reading is nearly useless — the vet needs data points, not recollections. A log makes the record-keeping easy — Diabnostic, for example: time, sugar, food and shot in a single entry.

When It Doesn’t Work

No blood — I don’t re-prick the same spot. I warm the ear again, try another spot or the other ear, switch lancets. After two or three attempts with no drop, I stop: today’s reading can be repeated in an hour. In my first month I had to learn not to chase the number at any cost. And the main thing: a home reading is data for a conversation with the vet, not a reason to change anything in the treatment. You do not touch the dose based on your own readings — that’s a rule, not overcaution.

First-Month Mistakes

Manishka struggled not because of the pain: I chased her around the apartment, restrained her too harshly, and was tense myself. A cat reads that faster than I can say “it’s okay.” Things improved when I stopped setting ambushes and started calling her onto the blanket instead. A second person sometimes helps — one holds, one pricks — and sometimes gets in the way if they fuss.

Strips failed more often than I expected: too little blood, smeared, damp, expired, the meter rejected the lot code, I touched the window with my finger. I burned through strips by the pack, got angry — the cat walked away. The right response to a failed strip is a pause and a breath, not “again, faster, before she runs off.”

The measurement became a stressor when I tied it to leaving for work: alarm goes off, no cat in sight, I’m already in my jacket, the lancet is nowhere to be found. Better to skip a reading than to fight for a number on adrenaline — mine and the cat’s: stress sugar almost always lies in one direction, upward, both at the clinic and at home. And a missed or questionable shot is no reason to improvise: agree with your vet in advance what to do in that situation. How insulin for cats works and what to do in the first days (your cat has been diagnosed with diabetes) are covered in separate articles.

The cat has the right to walk away once the drop is on the strip. At first I held her until the number appeared on the screen — she scratched, I gripped harder. Now, once the drop is on the strip, the cat is free; the number catches up on its own. How it worked out for us — in Manishka’s story.

Sources

1. Sparkes AH, Cannon M, Church D, et al. ISFM Consensus Guidelines on the Practical Management of Diabetes Mellitus in Cats. J Feline Med Surg. 2015;17(3):235–250 — stress hyperglycemia; home monitoring as the preferred method of control.
2. iCatCare Consensus Guidelines on the Diagnosis and Management of Diabetes Mellitus in Cats. J Feline Med Surg. 2025;27(11) — including a video demonstration of glucose sampling from the ear tip.
3. AAHA Diabetes Management Guidelines for Cats. J Am Anim Hosp Assoc. 2026;62:65–93 — blood sampling sites and home measurement technique.