Diatomaceous Earth and Dogs

Diatomaceous earth is a substance composed of diatoms, fossilized single-cell algae. Most commercially diatomaceous earth, or DE, is made of amorphous silicon dioxide and may contain small amounts of crystalline silicon dioxide. The substance can be used to protect dogs, both internally and externally, from parasites.

Adult Golden Retriever  Scratching fleas
Dog itching
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Dead Diatoms

Phytoplankton that exist in huge numbers in large bodies of water, diatoms usually bloom to enormous populations once annually, sometimes twice. When the massive colonies perish, their remains settle in a layer and eventually fossilize. As with other types of fossils, diatomaceous sediment is excavated today from land masses that once were covered by water. This is ground into DE and sold for various purposes.

External Uses in Dogs

Diatomaceous earth, also referred to as fossil shell flour, is usually administered in powder form. According to the National Pesticide Information Center, food-grade DE is nonpoisonous; you can safely rub it on dogs, and you can sprinkle it in dog kennels and on bedding, to protect against ticks, fleas, spiders and other parasitic insects. The powder grains have sharp edges that slice open their innards and dry them out.

Internal Uses in Dogs

When mixed with food, DE works as a strong yet safe abrasive that removes intestinal parasites, including worms, from dogs’ digestive tracts. DE also has the ability to absorb bacteria and fungi. Dosage is based on the size of your dog and what you’re treating -- seek your vet's input. DE starts working within a week, though the duration of DE treatment varies on the type of parasite and level of infestation. Your vet is a good source of information for specific treatment guidelines.

DE in the Home

Sprinkle DE on your carpet, leave it overnight, then vacuum. Outside, spread DE on your lawn. The amount you’ll need to use varies based on the product, the humidity of your environment, weather conditions and the severity of infestation. For best results, read and follow manufacturer’s guidelines.

Side Effects

Inhaled, DE has the potential to irritate mucous membranes in the mouth and nose. Apply it to dogs in a well-ventilated area, steering clear of the face and eyes. Wear a dust mask to protect yourself. Have your vet's approval and his dosage suggestion before you administer DE or any substance to your pet. The vet should give an exam before you start DE, too: If your pup has health problems or a severe parasite or infestation problem, veterinary care may be the preferable treatment.

DE Cautions

Pet owners may choose DE over other forms of chemical pest removal and prevention because it’s a natural product, but not every available type of DE on the market is safe. Some contain toxic elements -- for example, DE pool filter formulas. Always look for food-grade products to ensure safety.