Dogs that develop anxiety usually do so around the onset of social maturity.

This happens somewhere around 12 to 36 months of age. Anxiety also seems to accompany normal declines in thinking, learning, and memory for many dogs in their senior years. It’s fairly normal for an aging, or senior dog to especially develop separation anxiety as they begin to lose their hearing and eyesight. But fear and anxiety often get increasingly worse in old age (what that depends on the breed/size of the dog).

Anxiety usually starts quietly and escalates.

Some signs of building chronic anxiety include your dog chewing on her paws, licking body parts obsessively, or increasing whining for no apparent reason. As it gets worse, she might start trembling, tuck her tail, withdraw socially, sleep excessively, or slip away into another room and hide out from her humans. Anxiety rarely appears suddenly, though certain events can provoke it—like fireworks or arguing, or violent outbursts from humans. A dog forced into an unfamiliar and frightening experience can experience acute anxiety. Acute anxiety usually shows up as panic. She might bolt, bark excessively, or chase her tail obsessively. Though it might seem harmless albeit annoying to a human, it’s quite scary and upsetting to the dog going through it. At it’s worse, sheer panic anxiety can cause a response from the sympathetic autonomic nervous system, including diarrhea and vomiting. In the long term, it can show up as lesions or sores from your dog licking and biting herself.

Anxiety according to the experts.

In addition to aging, scientists have found a profound link between infectious disease (primarily viral infections in the central nervous system) and toxic conditions (such as lead poisoning) when trying to identify the source of anxiety. Illness can exacerbate fear and anxiousness. When a dog doesn’t feel good, you should expect to see some classical signs of anxiety like fearfulness, hiding, and whining. Some other causes of anxiety include:

• Social and environmental deprivation at an early age (dogs taken from the litter to early). Dogs isolated up to 14 weeks of age can become habitually fearful of other dogs or humans.
• Researchers have also found that phobias and panic attacks (both forms of anxiety) can result from an inability to escape or get away from the stimulus causing the phobia and panic, such as being locked in crate for hours on end with no human interaction (another reason to not get a new puppy if you have a fulltime job and there is no one else around to care for her, or you can’t afford to take her to daycare).
• Repeated abandonment. Dogs who have had multiple owners, have been rehomed more than once, or experienced prior neglect, can lead to serious separation anxiety. More rehoming could make this condition worse.

What can you do to help with your dog's anxiety?

Book an appointment with a veterinarian and have your dog evaluated for conditions that might be causing the behavior, such as brain or thyroid disease. Blood tests will rule out or confirm several neurological possibilities. If your veterinarian diagnoses a basic early stage anxiety, they may recommend medication—but usually they’ll want you to try some behavior modification first. Incidentally, profound fear and anxiety has been genetically linked to certain dog breeds, including the Bernese Mountain Dog, Border Collie, Chesapeake Bay Retriever, German Shorthaired Pointer, Great Pyrenees, Greyhound, Siberian Husky, and Standard Poodles, among others. Try these too:

• Music. The latest research shows that dogs respond well to classical music. It certainly worth a try, especially if you run in on a loop sound system when you aren't home.
• Bach Flower Remedies. One of the most powerful calming therapies for dogs is Rescue Remedy. Many rescue groups consider it the number one go-to for anxious pups in transition. Dr. Bach created 38 different flower essence remedies to address a wide range of emotional body imbalances. It may sound foo-fooish, but it works. Rescue Remedy is made from a blend of impatiens—a flower essence that helps with impatience, irritability and agitation; clematis—a remedy for spaciness or faintness, and detachment; Rock Rose, a remedy for terror and panic; Cherry Plum—for loss of self control; and Star of Bethlehem—a flower essence that addresses trauma or grief.
• Pheromones for anxiety. Chemical substances produced and released into the environment by an animal, especially a mammal or an insect, can affect the behavior or physiology of others of its species. Dogs use them to communicate (hence the constant need to check the “pee mail” on bushes and sign posts). The vomeronasal organ is located between the nose and mouth, and is highly sensitive to pheromones. Certain pheromones, called calming or appeasing pheromones, can sometimes help relieve stressed pets. Pet pheromone products are said to mimic natural dog pheromones and come in various forms, including sprays, plug-in diffusers, wipes, and collars.
• Get Your Dog Outside. Exercise not only works to alleviate depression and anxiety in humans but is essential for the mental health of dogs as well. Walk her daily. Twice daily is even better.
• Thunder Shirts/Coats. It is said that these anxiety-reducing wraps were inspired by Temple Grandin. The well-known autism-awareness-advocate invented a “hug machine” for humans with autism after noticing the way a light squeeze calmed cows before slaughter. The Thundershirt (also called a Thunder Coat by some) uses deep pressure to help relieve anxiety. There isn’t enough research to prove they work, but anecdotal evidence suggests they’re worth a try. They definitely won’t hurt your dog, though your budget may take a hit.
• Reduce Your Own Stress. If you’re experiencing a lot of stress in your life, some of it is going to just naturally rub off on your emotional sponge dog. Find ways to reduce stress in your own life, and think twice before raising your voice in anger when your dog is nearby. Literally, take loud angry arguments outside, or to a friend or therapist.