More than 3 pinhead red or purple spots on the gums, belly, or inner eyelid is a bloodwork case within 24 hours, not a wait-and-see. Bruises in cats rarely come from bumping into furniture; the skin is loose and the furniture is familiar. They usually mean one of 3 things: too few platelets, a clotting factor that is not working, or a toxin that removed the ability to clot at all. The exam is cheap and fast, and the answer changes what you do tonight.
Separate a bruise from pigment and from dirt
Flat orange-brown freckles on the nose, lips, and eyelids of an orange or tortoiseshell cat are lentigo: 1 to 3 mm, present since 1 to 2 years of age, unchanged for months, and harmless. A bruise is red to purple at hour 0 to 24, blue-green at 48 hours, and yellow-brown by day 5 to 7, and it fades when you press it. Dirt and flea feces wash off with a damp cloth; petechiae do not. Photograph the same 3 spots at 24 and 48 hours with a coin beside them, because the color timeline is diagnostic information your vet cannot recover later.
The 3-spot rule and where to look
Count in 3 places: the gum line above the upper canine, the midline of the belly between the last rib and the groin, and the inner surface of the ear pinna. Three or more spots in any one of those places, or any cluster that is new since last week, gets bloodwork. Two isolated specks in a cat that is eating and playing can be watched for 48 hours with photos. Also look at the whites of the eyes and the roof of the mouth, where petechiae show before the fur hides them. A bruise larger than 2 cm across with no known injury counts as 3 spots.
The panel that answers it in one visit
Ask for a CBC with a platelet count, not just a hematocrit. Normal platelets run 150,000 to 500,000 per microliter. Under 100,000 is abnormal, under 50,000 risks bleeding from everyday knocks, and under 30,000 is an emergency that can bleed into the brain or gut. Add PT and aPTT for the clotting factors, and a buccal mucosal bleeding time if the platelet number looks normal but the cat still bruises. Results are usually back within 1 to 24 hours, and the whole panel typically costs less than a dental cleaning.
| Finding | Test | Turnaround | What the number means |
|---|---|---|---|
| 3 or more petechiae | CBC with platelet count | 1 to 4 hours | Under 50,000 per microliter: bleeding risk today |
| Platelets under 30,000 | Repeat count plus smear review | 2 to 6 hours | Spontaneous bleeding, treat within 24 hours |
| Bruise with normal platelets | PT and aPTT | 2 to 24 hours | Prolonged PT: suspect rat bait or liver disease |
| Bleeding at 2 or more sites | BMBT plus factor screen | Same visit | Over 4 minutes: vessel or platelet function problem |
| Known bait exposure | PT at 48 and 96 hours | 2 to 24 hours each | Normal at 96 hours lowers the risk sharply |
The 5 questions that matter for a poisoning history
Vets ask in a set order for a reason. 1, What product, and is the active ingredient brodifacoum, bromadiolone, difenacoum, or chlorophacinone? Those second-generation anticoagulants block vitamin K recycling and can keep a cat bleeding for 4 to 6 weeks after one meal of bait. 2, When, to the hour, because decontamination is worth doing within 2 hours and mostly pointless after 6. 3, How much was in the box, and how much is gone. 4, Are there other pets, or dead rodents in or around the house, which is the same exposure by a different route. 5, Any human medication: 1 regular-strength aspirin tablet is enough to impair platelets in a 4 kg cat for 5 to 7 days, and ibuprofen or acetaminophen are worse.
When platelets drop on their own
Immune-mediated thrombocytopenia, FeLV or FIV infection, FIP, severe liver disease, and some cancers all produce the same skin picture as bait. That is why the panel comes before treatment: vitamin K1 given for a bait case does nothing for an immune case, and steroids given for an immune case do not fix a toxin. A cat with 3 or more bruises, a nosebleed, and a platelet count of 20,000 needs a plan built in hours, sometimes with plasma or a transfusion, not a supplement and a recheck in a month.
The thresholds that mean today
Go now for petechiae on the gums plus any bleeding from the nose, blood in the stool or vomit, blood in the urine (red or brown urine), a bruise wider than 2 cm, gums that are pale to white, a resting breathing rate above 40 per minute (the fast-breathing check), a seizure, or a platelet count under 30,000 from any lab. Go within 24 hours for 3 or more new spots, 2 or more bruises with no injury, or any possible bait contact in the last 14 days even if the cat looks normal; look the product up before you drive. Go within 72 hours for a single new spot plus poor appetite for 3 days.
What to bring and what to stop
Bring the bait box or a photo of the label, the exact times, a list of every medication in the house including supplements, and your 24 and 48-hour photos. Stop all aspirin, ibuprofen, and human painkillers immediately; a single 325 mg tablet is 80 mg per kg for a 4 kg cat, far past any safe dose. Do not induce vomiting at home, and do not start vitamin K on your own, because the dose is set by the PT result and the product's ingredient.
First 5 steps tonight
1. Count spots in the 3 checkpoint areas and photograph them beside a coin. 2. Press each spot for 3 seconds; if it does not blanch, it is blood. 3. Check the nose, stool, and gums for a second bleeding site. 4. Collect the bait box and write the hour of exposure. 5. Call and ask for a CBC with platelets plus PT and aPTT, not just a check-up.
Terms mentioned in this article
Frequently asked
Is a single bruise on a cat an emergency?
One isolated spot in a cat that eats, plays, and jumps normally can be photographed and watched for 48 hours. A bruise wider than 2 cm, 3 or more spots in one checkpoint area, or a second bleeding site such as the nose moves it to bloodwork within 24 hours. Growth over 24 hours is the sign that matters most.
Which blood tests actually find the cause?
A CBC with a platelet count is the first step, read against 150,000 to 500,000 per microliter. Add PT and aPTT for clotting factors, and a buccal mucosal bleeding time when platelets look normal but bruising continues. Results usually return within 1 to 24 hours, and the combination separates toxin, immune disease, and liver disease.
How long after rat bait can a cat still bleed?
Second-generation anticoagulants such as brodifacoum block vitamin K recycling, so bleeding can appear 2 to 7 days after a single meal and continue for 4 to 6 weeks without treatment. A PT at 48 and again at 96 hours is the standard check. Normal results at 96 hours make serious poisoning much less likely.