What are the current deworming recommendations for cats, including indoor-only cats?

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Year-round broad-spectrum parasite control is recommended for all cats, including indoor-only cats, regardless of lifestyle. The protocol should provide efficacy against heartworms, intestinal parasites, and fleas as a baseline for every patient, with tick control added based on individual risk assessment.14 Indoor-only cats carry genuine parasite risk and should not be exempt from routine deworming. Infectious agents can be introduced via fomite transmission on owners' clothing, shoes, or body, and indoor cats may be exposed to pathogens during veterinary visits.2 Even cats described as strictly indoor may be at risk for parasitic infections, and negative fecal testing does not rule out infection.1 For kittens and newly acquired cats with unknown medical history, prophylactic broad-spectrum treatment is prudent at the time of acquisition. This approach eliminates existing infections and reduces the risk of further infestation. Canine and feline housemates should be treated concurrently when a new kitten or cat is introduced to the household.1 Risk stratification should guide deworming frequency beyond the baseline recommendation. The three highest-risk behaviors identified in cats are hunting, catching prey, and contact with children or the elderly.6 Using European Scientific Counsel Companion Animal Parasites (ESCCAP) risk groupings, 33–68% of cats fall into the highest risk category (Group D) depending on country, and the majority of cats in that group require monthly deworming — yet cats average only 2.2 deworming treatments per year across surveyed populations, well below the four-times-per-year frequency demonstrated to reduce zoonotic Toxocara spp. egg shedding.6 Deworming should not delay vaccination in parasitized kittens. There is no current evidence that endoparasite burden impairs feline vaccinal immune responses, and protection against life-threatening viral disease takes priority.7 Environmental hygiene complements pharmacologic control. Preventing cat