As expressive and loving as dogs are, they can’t tell you when they feel sad or blue. But like people, they can get depressed, and often for some of the same reasons.

Dogs may feel intense pain, for example, over their owners' divorce, kids departing for college or a death in the family, according to Dan Teich, DVM, owner of District Veterinary Hospital in Washington.

Some dogs, such as rescue dogs, may also be dealing with stress or past trauma, including abuse. And others may simply be suffering from lack of attention and exercise.

“Depression in dogs is real, although it can be attributed to many different causes,” says Teich. “It’s very difficult to prove a bonafide chemical imbalance in a dog. The main course of treatment that we will attempt first is determining whether the dog is receiving adequate attention and exercise.”

“More than half the cases I see involve latchkey dogs from working families who are out of the house 8 or more hours a day and the dog is left alone,” he adds.

Related: Is Your Dog Stressed Out?

Warning signs of dog depression

How do you know if your pooch is depressed?

“Obvious changes in mood and low energy level that doesn’t go away are signs of depression,” says Linda Brodzik, who directs In Relation with Dogs, a Minneapolis dog-training facility specializing in canine behavior modification.

Here are some other signs your dog may be suffering from depression, according to Teich.

No energy and constant sleeping. Most dogs sleep a lot, but much of their snoozing occurs when you’re out of the house. If your dog still sleeps when you return and pays little to no attention to you, there may be a problem.

Hiding and irritability. If your dog spends an unusual amount of time hiding, say, under the bed or in a closet, she may be depressed, says Teich. Becoming withdrawn and wanting to be left alone are often signs of an underlying emotional issue.

Indifference and listlessness. Your dog won’t cry, like some people do when they’re depressed, but she might become sluggish and lethargic, losing interest in having fun. Rare is the dog who suddenly loses interest in regular activities — retrieving a ball, going for a walk and of course, chasing squirrels. If she’s no longer excited by her favorite activities, she may be depressed, says Teich.

Incessant paw-licking. If your dog is licking and chewing her paws more more than usual, this may be a sign of psychological issues. Licking paws is comforting for dogs, in much the way toddlers will suck their thumb for comfort.

A limp tail. Dogs reflexively wag their tails to show excitement, happiness and interest in an activity. If your dog’s tail droops limply toward the ground and seldom moves, it could be a sign of depression, says Teich.

Indoor “accidents.” A well-trained dog will not ordinarily start relieving itself indoors. Accidents will happen, but if this is a sudden and recurring behavior, it could indicate a psychological or medical issue.

Changes in appetite. A depressed dog may lose weight from not eating. On the other hand, some dogs, like people, seek comfort in food and overindulge, leading to weight gain, Teich says.

Since dogs are so empathetic, responding to owners’ moods and often reflecting them, Teich suggests doing a mood check on yourself. If you are depressed, he says, this could be rubbing off on your pet, who can sense your change in mood.

Exercise and attention go a long way

Don’t assume depression is the cause of your dog’s woes; have her checked out by a veterinarian to rule out any medical problems. But if your vet agrees Rover has the blues, what should you do to help your canine back to his normal fun-loving self? Here’s what Teich and Brodzik recommend.

Related: 13 Health Symptoms Dog Owners Should Never Ignore

Get your dog outside and active. “Increase activity, play and walking: That’s what we do,” says Brodzik. “When dogs are anxious or depressed, they may not have much interest in play. But getting them out there, getting them active, it’s what you need to do. Get the dog out walking more.”

Consider hydrotherapy for a disabled pooch. If pain and immobility from arthritis, cancer or a car accident makes it hard for your dog to romp around or even walk, that may affect his spirits. Look into a water therapy clinic, in which he can exercise safely in warm water, says canine rehabilitation specialist Nicole Rosell of Holistic Veterinary Care in Oakland, California.

Related: Hydrotherapy for Dogs: Could It Help Your Pooch?

Lavish attention on your pooch. “Spend more time with your dog. Animals respond to that extra attention and care,” says Brodzik.

Look into a companion for your dog. If you can't take your dog to work and have to leave him home all day alone, consider a dog walker, doggie day care or simply another dog in your home. Having a canine friend in the house might take care of the depression. “If dogs are social with other dogs, that may help,” says Brodzik.

Consider a pet behavior specialist. In the absence of physical problems, you may want to consider taking your dog to a canine behavioral specialist or even a pet psychologist. Asks lots of questions, Brodzik advises, since the field is unregulated. “If you’re thinking of working with someone, check out their credentials in terms of education and get references,” she says.

Antidepressants should be a last resort, says Teich. “Ideally, if you have a very willing pet family to work through the problems with training and increasing activity, we try to avoid medications.” These drugs can cause dependence, he says.

If a pet family needs extra help, vets can try an antidepressant, usually generic Prozac, says Teich. “There are usually no major side effects,” he says, adding that “in rare cases, a very small percentage of dogs get too excited from the medication.”

Remember, only a licensed vet can prescribe these medications. Unless drugs are the only recourse, Teich says, love, patience and good care may be the best Rx for overcoming dog depression.

Steve Evans, MA, is an award-winning journalist with more than 20 years experience in daily news, investigative, health and business journalism. Among other jobs, he has served as managing editor of the Central Virginia Newspaper Group, as a senior writer for SNL Financial and as a staff writer for The Progress Index and the Richmond Times-Dispatch.