Are therapy sessions for someone diagnosed with sensory processing disorder a deductible medical expense?

Deductible medical expenses include the cost of treatment for the purpose of affecting any structure or function of the body. While the IRS has not ruled on your specific condition, having a medical diagnosis and obtaining treatment for it would seem to meet the tax law requirements for deductibility. Of course, itemizing is required, and only total medical costs in excess of the applicable threshold (10% for most taxpayers; 7.5% for those age 65 and older).