Treatment and Relief through Emerging and Accessible Therapy for PTSD Act or the TREAT PTSD Act This bill requires the Department of Veterans Affairs (VA) and the Department of Defense (DOD) to furnish stellate ganglion block to certain veterans or members of the Armed Forces (including reserve components) diagnosed with post-traumatic stress disorder (PTSD). Blocking the stellate ganglion (a group of nerves at the base of the neck) by injecting a local anesthetic is a treatment that may alleviate PTSD symptoms. The bill authorizes this treatment for any veteran or member of the Armed Forces who (1) is enrolled in the VA health care system or TRICARE program, (2) has been diagnosed with PTSD, and (3) has elected to receive stellate ganglion block after being informed by a physician of the risks and benefits. Such treatment may be furnished at a VA medical center, DOD medical facility, or through health care provider under the Veterans Community Care Program or TRICARE health insurance program. The bill also requires the VA and DOD to update the VA/DOD Clinical Practice Guideline (CPG) for the Management of PTSD to ensure that information about stellate ganglion block is included.