Increasing Behavioral Health Treatment Act This bill repeals restrictions that generally prohibit federal payment under Medicaid for services provided in institutions for mental diseases (IMDs) for individuals under the age of 65. (Currently, states may receive payment for such services through certain mechanisms, such as through a Medicaid demonstration waiver.) The bill also requires state Medicaid programs that cover IMD services to improve patient access to outpatient and community-based behavioral health care, expand crisis stabilization services, facilitate care coordination between providers and first responders, and report specified information relating to IMD utilization and costs.