Wow this is incredible. I’ve suffered from hppd for almost 4 years now and I’ve just discovered I have antibodies to my GABA-B receptors. This means I have autoimmune encephalitis and there is treatment for it. I had a suspicion if others with hppd also had a form of autoimmune encephalitis and this confirms at least some others do. Having anti achr antibodies means you have autoimmune encephalitis and it could be paraneoplastic. Please look on Autoimmuneencephalitis.net and look under the antibodies of autoimmune encephalitis section. It talks about all of them. To treat I’ve started doing IVIG therapy and will move onto a therapy called Rituximab which is an immunosuppressant. I’ve noticed some slight improvements from the IVIG but I have just started treating so nothing major yet. How did you hppd begin?