Can Cats Drink Cow’s Milk?

Mostly no. Many adult cats are lactose intolerant, so cow’s milk often leads to diarrhea or stomach upset. A rare small lick is usually fine, but water should be the drink of choice.

Adult cats often lack lactase, the enzyme needed to digest lactose in milk.
High lactose loads draw water into the gut, causing loose stools and gas.
Milk’s calories can displace balanced cat food and skew nutrition.
Creaminess rewards begging, reinforcing a daily habit that backfires later.
Individual tolerance varies; stress or recent diet changes can reduce tolerance.

Track: note date/time, milk amount, and any changes in stool (soft, watery), gas, vomiting, lethargy, or litter-box urgency within 24–48 hours. Log frequency if it repeats.
Portion rule: if you must test, start tiny—1 teaspoon of lactose-free cat-safe milk alternative or water-thinned plain lactose-free milk. Wait 48 hours. No symptoms? You may occasionally give up to 1–2 teaspoons for a 4–5 kg cat.
Routine: keep fresh water available in two to three locations; refresh twice daily. Offer wet food once daily to boost hydration if your vet says it fits the diet.
Environment: use a stable feeding spot away from litter and busy walkways; shallow, wide bowls reduce whisker stress and encourage drinking. A quiet water fountain can help some cats drink more.
Attention management: avoid rewarding meows with milk. Instead, redirect with play (5–10 minutes of wand toy), then a small portion of regular food. Set consistent feeding times to reduce begging loops.
Stability check: maintain any new routine for 10–14 days before judging results. If stools normalize and begging drops, keep the plan; if not, remove dairy entirely and continue the log.

Diarrhea, vomiting, or bloating lasting more than 24–48 hours after dairy.
Blood in stool, black/tarry stool, or sudden dehydration or lethargy.
Repeated GI upsets from very small amounts or from lactose-free products.
Kittens under 12 months with poor growth, after giving any milk substitute.
Cats with chronic conditions (pancreatitis, kidney disease, IBD) reacting to dairy.
Sudden change in thirst/urination or weight unrelated to diet treats.

This is general pet-care guidance, not veterinary advice; when in doubt, contact your vet.