About Severe Itching & Vomiting in Dogs

By Bethney Foster

Itching and vomiting are common symptoms exhibited by sick dogs. These symptoms, when separate from each other, can indicate a wide array of health problems. However, when the two symptoms occur at the same time, the field of possible causes narrows. If your dog is exhibiting itching or vomiting, or the two symptoms in combination, you should likely take your pet to a veterinarian for examination and diagnosis. Among the possible causes are parasites, allergies or skin cancer.


Tapeworms are a common parasite in dogs and can grow to be as long as 2 feet in length. They are made up of small segments that sometimes separate from the longer parasite and appear in your dog's stool, looking like a piece of rice. There are various types of tapeworms, but the type most common in dogs is contracted when the dog eats an infected flea. In addition to seeing the segment of the tapeworm in your dog's stool or around his anus, you may notice your dog biting or scratching at his anus or see him dragging his rump across the floor. If the worms move from the intestines to the stomach, the dog will vomit and there will likely be a tapeworm in the vomit. Treatment is a simple de-worming pill your veterinarian can provide. You may also want to examine your flea control measures and ensure they are adequate.

Flea Allergy

While fleas are a torment to nearly all dogs, some canines have such severe flea allergies that a single bite can cause symptoms that include vomiting and itching. The dog may severely scratch or chew himself, leading to large amounts of hair loss. There may even be open sores or scabs. The most common area on which you are likely to see these spots are just in front of the dog's tail on her back. Strict flea control is especially important to dogs with severe flea allergies. Your veterinarian can also give your pet an injection to ease her discomfort. Occasional medicated baths may also help.

Food Allergies

Like people, some dogs have severe allergic reactions to certain foods. Among the symptoms of food allergies are severe itching and vomiting and an inflammation of the ears. Canines commonly develop allergies to beef, pork, chicken, turkey and dairy products. Diagnosis and determination of what food is causing your dog's allergies are usually done through a prescribed hypoallergenic diet. The dog is fed the special diet exclusively for 8 to 12 weeks or even longer to conduct the test.

Salmon Poisoning

Salmon Poisoning Disease has been seen on the western coast of the United States. The parasite can make people, dogs and other animals sick if they eat trout, salmon or Pacific giant salamanders that are infected with a specific parasite containing the microorganism Neorickettsia helminthoeca. In addition to vomiting and itching, symptoms include lack of appetite, fever, diarrhea, weakness, swollen lymph nodes and dehydration. Symptoms usually begin 5 to 7 days after eating the fish, but it may be delayed by as long as 33 days. If not treated, death occurs in 90 percent of cases after 7 to 10 days. Treatment includes sulfonamides and supportive therapy to maintain hydration, electrolyte balances, nutrition and to control diarrhea.

Mast Cell Tumor

Mast cell tumor is a type of skin cancer. In addition to causing itching and vomiting in dogs, symptoms include a visible tumor, loss of appetite, bloody vomit, diarrhea, abdominal pain, dark or black feces, lethargy and various bleeding disorders. Treatment includes surgically removing the tumor, if possible. Sometimes radiation is used and, sometimes, the only treatment is palliative and not designed to extend the dog's life.