Giardia is a parasite that resides in the intestine of humans and animals. In dogs, it is found more frequently in older dogs than in puppies. Giardia is transmitted from dog to dog through infected faeces or through food, water or other substances that have been contaminated with infected faeces. Giardia causes vomiting and diarrhoea, and over a long period of time can contribute to weight loss and poor health. Fortunately, Giardia can be treated with several types of medication.
Options for Treatment
Metronidazole is a long-standing and popular choice for the treatment of Giardia. It is generally administered in 25 to 30 mg/kg doses over a five- to seven-day period. However, Metronidazole can be harmful to foetuses, so it should not be given to a pregnant dog. Side effects of Metronidazole include vomiting and anorexia, and in some dogs, liver toxicity and neurological problems can also occur.
Fenbendazole, known by the brand name Panacur, is a medication that is approved for treating roundworms, hookworms and whipworms, which are varying forms of intestinal parasites. Fenbendazole has been found to be effective in treating Giardia as well and is generally administered in 50 mg/kg doses daily for three days. It is safe for use in dogs over 6 weeks of age.
According to Drs. Foster & Smith, albendazole is effective in destroying Giardia. But despite being 50 times more effective than metronidazole, it has not been approved for use in dogs. Albendazole should be administered in two 25 mg/kg doses over a period of two days to cure Giardia. However, albendazole can cause serious side effects that include bone marrow injury and birth defects, so it should be used with caution.
Two other treatment options are tinidazole and Furazolidone. Tinidazole is given in 44 mg/kg doses daily for seven days, and furazolidone is given in 4 mg/kg doses once per day for seven days.
If you suspect that your dog has Giardia, make an appointment with your veterinarian. He can take a stool sample to confirm the diagnosis of Giardia, and make appropriate treatment recommendations.
Giardia can sometimes be difficult to cure, so you may need to make follow-up appointments with your veterinarian. There is no vaccination against Giardia, so follow through with treatment of infected areas and preventive measures to prevent another infestation.
Treat and prevent future Giardia infestations by cleaning up after faeces. Remove or conceal locations where water can collect and pool, and avoid areas where puddles and water run-off form. Clean and reseal concrete surfaces, and replace gravel. Use a combination of 1 per cent bleach and 99 per cent water to clean and disinfect infected areas.
Giardia can be transferred to humans, so take care when cleaning up infected areas. Wear gloves, don't touch your face, and change clothes and wash your hands thoroughly after being in infected areas or handling a dog that has or is thought to have Giardia.