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      This is the catch-all forum for posts. Discuss anything related to Hallucinogen Persisting Perception Disorder (HPPD) here.

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      A place to introduce yourself to the community and what you hope to seek out on this site. New members may share their experience and onset of HPPD and what drug(s) triggered it.

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      What are the symptoms? What do you feel encompasses HPPD?

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      The place to discuss pharmacological and other treatment options.

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      This is a location to talk about anything except your symptoms. Be respectful of other users, but any topic within the rules are open for discussion.

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  • Hallucinogen Persisting Perception Disorder (HPPD) support forum - HPPD, flashbacks, drug-induced visual snow syndrome and depersonalization/derealization.

    Common HPPD symptoms: visual snow, palinopsia (trails/afterimages), increased BFEP, increased floaters, ghosting, halos, starbursts, macropsia/micropsia, geometric hallucinations, closed-eye visuals, flashbacks, depersonalization/derealization, anxiety, depression, brain fog, cognitive dysfunction, tinnitus.

  • Recently Active Topics

  • Latest Posts

    • Thanks man, I appreciate your excitement! I wasn't even specifically looking for it, it just came by as a coincidence. I remember in one paper from Dr. Abraham it was mentioned specifically to not call HPPD a "loss" of neurons yet since it wasn't evident enough, instead, calling it an inhibitory "deficit" or something like that. Another interesting aspect of HPPD is DP/DR. It is known that DP/DR is a common comorbidity of HPPD. DP/DR could be caused by disturbances in frontal cortex regions, while the visual symptoms of HPPD seem to evolve mainly from the visual cortex only. It makes me think that the brain dysfunction is not be isolated only to the visual cortex, but may be more widespread in the brain.   Here is a cell culture study: (@Fawkinchit this is exactly the thing you want to do, how great is that! :P) "Ecstasy induces apoptosis via 5-HT2A-receptor stimulation in cortical neurons" https://www.sciencedirect.com/science/article/abs/pii/S0161813X0700071X Here is another study related to the dentate gyrus: (the dentate gyrus is a region inside the hippocampus) "MDMA and Glutamate: Implications for Hippocampal GABAergic Neurotoxicity" https://etd.ohiolink.edu/apexprod/rws_olink/r/1501/10?clear=10&p10_accession_num=ucin1460444662  
    • Hppd is a condition that is in some ways similar to ptsd and in some ways different. For ptsd some research indicates that there are some autoimmune links or that it is driven or made worse by inflammation in the brain. Injecting drugs into the brains of mice (I don't know if they used a reasonable dosage or not) is likely to cause inflammation and neurological changes. If the dosages are reasonable it is likely the mice will recover, however I am not sure if this is connected to hppd directly. The changes might be stress related. If hallucinogens cause damage to certain brain cells (which I think is a possibility) it might be by altering how nerves fire. If you slow down or stop a neurons activation for a while  it might "gasp for air" and have a patter of activation and inactivation that is abnormal. I could see how this might be toxic for neurons or select for neurons that function in a slightly different way from normal neurons. Like, for example, uv rays might make dark patches of skin grow larger as they aren't as effected by sun light compared to other areas of skin. Hallucinogen flashbacks might indicate that taking hallucinogens changes gene expression, how some or all neurons function or the pattern of  connectivity in the brain. And then under certain circumstances this pattern is activated. Stress for some people can cause a flashback I have heard. The 5HT2A is likely a trigger for hppd I think however there may be multiple complex things going on, rather than just damaged neurons. 5ht2a receptor is present in immune cells also, so it is also likely that a hallucinogen could prevent the immune system from working properly which may prevent proper brain repair. I think people on this forum have had mixed results with this method: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8987195/ but it may give insight it to what might be causing hppd. Clonazepam up regulates the 5ht2a  receptor is certain parts of the brain and down regulates it in other parts. https://cris.tau.ac.il/en/publications/clonazepam-treatment-of-lysergic-acid-diethylamide-induced-halluc
    • It appears its possible https://www.frontiersin.org/articles/10.3389/fncel.2017.00423/full https://www.frontiersin.org/articles/10.3389/fncel.2022.827628/full Also more info on interneurons https://www.sciencedirect.com/topics/neuroscience/5-ht2a-receptor https://elifesciences.org/articles/66960
  • Recent Status Updates

    • thequestioner827  »  David S. Kozin

      Hi David, I was wondering if you had a full text version of the paper you posted here:
      I have university access to PubMed and Medline but I'm still unable to find a full-text version, only an abstract like what is posted here.
      Thanks in advance!
      · 0 replies
    • since92  »  David S. Kozin

      Hi Dave, I see in your profile pic one of your original posts from 1999, then I see that you joined this one in 2010.  Is it possible to see posts from the forum that we all used to message on - I'm presuming that you and I were on the same one forum?   It's because another user and I are looking for people we messaged with back in 2003 but I think though that I had a different user name in those days.  Do you know of that forum and whether we can access posts from those days?  I would like to see those early posts of mine because they had a lot of info about how my HPPD developed etc..  Many thanks.
      · 0 replies
    • David S. Kozin

      Haven't slept longer than 4 hours in three days.
      My HPPD is off the charts.   will not be available at all today. Please contact Jay1 for all of your needs. 
      · 0 replies
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