Johnson's Garlic Tablets for Cats and Dogs 200 Tablets Johnson's Garlic tablets for Cats and Dogs is a herbal, dietary supplement, suitable for both cats and dogs. Garlic is a natural conditioner and cleanser; it also aids circulation and supports your pet's natural defence system. This beneficial supplement also acts as a natural repellent against fleas and deters worm infestation. Caution: Garlic can be toxic to cats and dogs. Do NOT exceed the dosage stated by the manufacturer and contact them directly if you require further information.