Service animals play a vital role for people with disabilities, and the IRS recognizes that by allowing related expenses as a medical deduction. The cost of buying, training, and maintaining a service animal is deductible as a medical expense when the animal is needed to help a person with a physical or mental disability. Deductible costs include food, veterinary care, and grooming for the animal. Like all medical deductions, you need to itemize and your total medical expenses must exceed 7.5 percent of your adjusted gross income. Emotional support animals may not qualify since they are not trained to perform specific tasks for a disability, so there is a distinction between a service animal and a comfort pet.