Heartworm treatment is an intensive process that causes significant short-term welfare impact while preventing the long-term harm of progressive cardiovascular disease.
Heartworm treatment requires owners to understand and accept a period of significant dog discomfort in service of long-term welfare. The melarsomine injections cause muscle soreness and pain at injection sites that affects mobility and comfort for several days. Enforced exercise restriction causes frustration in active dogs. The risk of pulmonary embolism from dying worm fragments dying in the lungs requires careful monitoring. Despite these treatment challenges, the welfare calculus strongly favors treatment: untreated heartworm causes progressive heart failure, chronic respiratory compromise, and eventual death in a prolonged decline of significant suffering. The access and cost barriers to treatment mean many dogs in underserved communities receive inadequate care, representing a significant welfare equity issue.