https://www.vetinfo.com/dog-chewing-tail.html
Dog chewing tail may be caused by stress, boredom, worms, fleas or tail fractures. The chewing of the tail can lead to infections, as the dog is able to cause wounds and bleeding. The tail chewing may be stopped by putting a lamp shade collar on the dog, but the cause of this behavior must be detected and treated, so that the chewing will stop also.
Causes of Dog Chewing Tail
The tail chewing behavior may be caused by different factors including:
Intestinal worms that may irritate the rectal area
Allergies to different pollens, grasses, dust mites, fabrics or chemicals
Boredom
Anxiety and stress
Fleas
Ticks
An object/insect that got tangled in the tail fur
Remaining fibrous tissues (in dogs with docked tails) which can lead to nerve pain and irritation
Trauma, involving the tail
Fractures in the tail area
Recognizing Tail Chewing
You will notice that your dog is preoccupied with chewing his tail and he may be fervently chewing and biting the area.
It may happen that your dog chews his tail in your absence (i.e. due to boredom while you are at work) so you may not even notice if your dog is chewing his tail. Watch out for symptoms such as wounds, scratches, bleeding or pus and foul odor in the tail area.
Diagnosing Tail Chewing
The causes of tail chewing may be difficult to detect; however, the vet will perform a few tests to rule out causes of tail chewing that may be easy to diagnose (i.e. internal worms, fleas or allergies).
The vet may also perform an x-ray to determine if there is a fracture in the tail area.
Behavioral problems, stress or boredom may be more difficult to diagnose.
Treatment for Tail Chewing
The treatment for tail chewing will greatly depend on the causing factor of the behavior.
If the causes of tail chewing haven’t been determined, the dog may receive a lamp shade collar which will stop him from chewing his tail and allow the wounds or the infection to heal; however, this is not a permanent solution; it may be used until you identify the factor causing the tail chewing.
The treatment may be made up of flea products or dewormers; make sure to apply these products and pills as indicated by the vet.
If the dog is bored, you should try to make sure he has toys while you are away and you should also offer more attention and play time, so that his energy won’t go towards chewing his tail.
Allergies may be managed with oral medication and topical ointments or if possible, by removing the allergen from the dog’s surroundings.
The stress trigger has to be identified and removed from the dog’s environment.
If the dog has caused serious damage to the tissues in the tail, these may have to be removed through surgery.
If there are infections caused by chewing, the dog should get some antibiotics.