Diagnostic tests are needed to recognize intestinal parasites. When a pet is ill with gastrointestinal symptoms, other tests may be needed to exclude other diseases, even if worms are obvious. These tests can include: A complete medical history and physical examination. This should involve questions about any vomiting, bowel movements, weight loss, health of littermates, previous deworming program, history of previous parasites and housing. Complete examination with abdominal palpation (feeling the abdomen) should be done.
Fecal analysis tests. The fecal sample is mixed with a solution that encourages microscopic ova (eggs) to float to the top and stick to a microscope slide for examination. A single fecal sample may not demonstrate the eggs in infected dogs in some circumstances. Some parasites-whipworms are a good example-shed ova intermittently. Some parasitic infections such as Giardia require a different approach to diagnosis (fresh sample of feces with examination of a saline smear under a microscope).
A complete blood count (CBC). In sick pets or those appearing anemic, a CBC can reveal anemia (as some worms cause intestinal blood loss) or elevated eosinophil count (common in parasitic infections). It is also helpful to screen for other infectious intestinal diseases (such as parvovirus).
Additional diagnostic tests may be recommend on an individual pet basis to exclude or diagnose other conditions or to better understand this disease's impact on your pet:
A test for parvovirus should be considered in puppies with acute or severe diarrhea or vomiting, especially when there is fever or blood in the stool. This infection is a very common cause of diarrhea in dogs. Worms are often shed with this condition (from pre-existing intestinal parasite infection).
Abdominal X-rays may be needed in some cases of severe vomiting or if the abdomen is abnormal to palpation.
The best course for managing intestinal parasites is prevention. Treatment of intestinal parasites must be individualized based on the severity of the condition and other factors that must be analyzed by your veterinarian. Treatment may include:
Deworming. Puppies are dewormed routinely for roundworms and hookworms at the time of "puppy shots, " but worms can also affect mature dogs. Regular stool examinations can detect intestinal worms in most cases. Some of the newer heartworm preventatives also prevent intestinal parasites (and some prevent fleas as well!).
Fecal exam. A yearly fecal sample is recommended for adult dogs. Adult dogs typically acquire worms when they lick up microscopic eggs present in contaminated soil or grass. Mature dogs develop resistance to most intestinal parasites, but the whipworm can still cause problems leading to signs of colitis. It is to detect this worm with a stool sample, but it responds to appropriate deworming medicine.
Drug therapy. Several drugs available concurrently prevent heartworm disease and prevent or treat intestinal parasites. See your veterinarian for details. These products include Interceptor® (Milbemycin), Heartguard Plus® (Ivermectin + pyrantel tartrate) and Revolution® (selamectin).
Treatment for parasites is often based the fecal analysis. Common treatments may include:
Roundworms (Toxocara infections)-pyrantel pamoate (Nemex®) or fenbendazole (Panacur®) is commonly used to treat roundworms and hookworms.
Hookworms (Ancylostoma caninum, Ancylostoma braziliense and Uncinaria Stenocephala)-pyrantel pamoate is commonly used to treat roundworms and hookworms.
Whipworms (Trichuris vulpis, T. Campanula, T. Serrata)-Dogs are treated once daily for three consecutive days and repeated in 3 weeks with fenbendazole (Panacur®). Some veterinarians recommend a third treatment in 3 months. This drug also treats roundworms, hookworms and tapeworms (Taenia spp.).
Physaloptera (stomach worm)-this can be treated with pyrantel pamoate.
Strongyloides-often treated with fenbendazole (Panacur®) or pyrantel pamoate (Strongid T®, Nemex®) for 5 days.
Tapeworms (Diplylidium caninum, taenia pisiformis)-praziquantel (Droncit®), epsiprantel (Cestex®) or febantel + praziquantel (Versom®); fenbendazole is effective for taeniid infection. Dipylidium infections also require prevention with flea control (fleas are the intermediate host). Prevent dogs from unsupervised hunting (rabbits are the intermediate host of Taenia pisiformis).
Coccidia-can be treated with sulfadimethoxine for 10 days or trimethoprim-sulfa for 7 days.
Giardia-can be treated with various drugs including metronidazole (Flagyl®) for 5 to 10 days.