My 6-year-old dog hasn't eaten anything for two days — should I try a different food?

A dog who normally inhales his dinner and has eaten nothing for two days needs to be examined — not offered a different food. Appetite loss is one of the least specific and most reliable signs there is: nausea, pain anywhere (teeth, back, belly, joints), fever, an obstruction from something swallowed, kidney, liver or hormonal disease. Tempting him with roast chicken usually just means you find out a day later, and a dog with a sock in his gut is worse by then. Puppies, toy breeds and diabetic dogs crash faster; for them this is a same-day problem.

Before the appointment, gather what the exam cannot give you. Is he drinking and urinating? Has he vomited, even foam? When did he last pass stool, and does his belly look tucked up or feel tense? Look at his gums — they should be a healthy pink and moist. Take an inventory of what is missing from the house: a toy, a corn cob, a sock, underwear.

Bring a fresh stool sample and a list of anything new in the past week — a treat, a chew, a medication, a change at home.

Your vet will weigh bloods, x-rays and a watch-and-recheck against each other based on what the hands find, and that decision is a great deal better than a guess made across a screen. Do not wait at all if he starts vomiting repeatedly, becomes wobbly or unusually quiet, retches without bringing anything up, or his belly starts to swell.