What Flea Prevention Is Safe For Pregnant Dogs. Prescribed by vets, revolution is a topical flea and heartworm medication that's considered a safe flea control for pregnant dogs. Generally, topical flea medications are acceptable treatments for pregnant dogs.
Add more every three weeks. Frontline flea and tick preventative contains fipronil, an active ingredient. The following flea and tick products are tested for safety during pregnancy and lactation in dogs: