Doxycycline Compounded Oral Liquid for Dogs and CatsDescription Description Doxycycline is a tetracycline antibiotic prescription medication used to treat infections caused by several different microorganisms in dogs, cats, and small animals. The drug is often prescribed to dogs for heartworm disease, Lyme disease, anaplasma (tick borne), periodontal disease (teeth and gum) Toxoplasma, and Neorickettsia helminthoeca (salmon poisoning). Doxycycline is a broad spectrum antibiotic, which means it can