Can dogs drink milk?

Puppies produce lactase to digest their mother's milk. After weaning, production typically falls, and by adulthood many dogs have too little to digest a large drink of milk. Undigested lactose draws water into the gut and ferments, causing wind, bloating, and loose stools.

Cow's milk contains about 4.7 g of lactose per 100 ml.

To see whether your dog tolerates milk, give a tablespoon for a small dog or a few tablespoons for a large one. Watch for gurgling, gas, or soft stools over the next 12 hours. Dogs that are fine can have a small splash occasionally, but milk still adds calories, about 65 per 100 ml for whole milk.

Lactose-free milk is gentler on the gut but still adds fat and calories.

Do not give cow's milk to young puppies as a substitute for their mother's milk. It has a different balance of nutrients and often causes diarrhea. Orphaned or underweight puppies need a puppy milk replacer, and your vet should guide the amount and schedule.

Weaned puppies eating a complete puppy food do not need milk at all.

Chocolate milk, coffee drinks, and milkshakes bring chocolate, caffeine, sugar, or sweeteners that are not safe. Condensed milk is very high in sugar. Stick to plain water as your dog's everyday drink. Goat milk, kefir, and plant milks each come with their own considerations, so check before swapping one for another.