It is said that we are now in a 'psychedelic renaissance', where the myth-enshrouded and potent substances are again examined under the lens – or rather, examined in the brain scanner and in well-decorated treatment rooms all over the world. There is a growing body of research on the substances' consciousness-altering mechanisms of action and potential in the treatment of mental disorders, addiction, existential despair due to life-threatening illness (1), chronic pain conditions (2), and so forth. Decades of prohibition and scientific stigma have been replaced with enthusiasm, hope, and media coverage of ecstatic experiences and dramatic improvements from deep suffering. It's an exciting development that hopefully will benefit many in the long run. At the same time, the balance is demanding, and the well-known pendulum can sometimes swing too far in the opposite direction (3). Weaknesses in the research may be under-communicated, as well as risks for vulnerable groups, the demanding psychological processes, and less-known adverse effects (4). This is especially relevant for the use of psychedelics outside of clinical trials, where the same safety measures and professional follow-up are not in place. At Psykolyse, we are in contact with many users who experience various negative effects after the use of psychedelics, and in this article, we will describe some of this less-discussed landscape.
Frightening experiences and anxiety reactions
"Every exertion of my will, every attempt to put an end to the disintegration of the outer world and the dissolution of my ego, seemed so much wasted effort. A demon had invaded me, had taken possession of my body, mind, and soul… I was seized by the dreadful fear of going insane. I was taken to another world, another place, another time. My body seemed to be without sensation, lifeless, strange." This is how chemist Albert Hoffman describes the first-ever planned LSD experience, the substance he himself discovered, in the book LSD: My Problem Child. That the first-ever acid trip was a terrifying and psychologically demanding experience is interesting in itself. Even more interesting is the content of the experiences Hoffman describes, as they have proven to be far from unique and shed light on how psychedelic experiences sometimes create acute mental crises and persistent difficulties afterward.
(a*) He is said to have absorbed some LSD through the skin at an earlier time by accident, which motivated him to test the substance by ingesting what he mistakenly assumed was a low dose (250 micrograms).
The direct experience can be very frightening, and like Hoffman, many have felt a tremendous loss of control when faced with overwhelming internal reactions. A recurring theme is an experience of annihilation, a feeling that one is psychologically or actually about to die (5). In stark contrast to a euphoric dissolution of our usual self-experience that characterizes the classic mystical experience of unity. Other recurring themes are fighting a losing battle against enormous forces, ending up in 'endless' torment, or having inflicted permanent and irreparable damage. Psychedelic experiences are notoriously context-sensitive, where one in a vulnerable and extremely susceptible state can be strongly marked by chaotic and unpleasant events. It can also be unpredictable how one reacts at a given time, even with effort made in preparation and optimization of the setting. The specific content of such an experience can include everything from unexpected reactivation of previous traumas in their rawest form, to an experience of being possessed or invaded by dark forces or alien beings (6). Good examples are described here and here.
There is an ongoing discussion in many user groups about whether one should call difficult and frightening experiences with psychedelics 'challenging experiences' instead of the classic 'bad trips' (7). That is to say, demanding experiences that are not inherently negative but also offer the opportunity for insight and personal growth. Such a nuance fits well with studies on negative experiences, where most also found the experience to be educational and rewarding (8). However, our experience from talking with users is that there are also negative experiences that have been outright harmful without obvious bright spots afterward. Many who have struggled with this have felt an extra burden of being distrusted by friends with positive attitudes towards psychedelics, where a kind of idealization of the substances as necessarily therapeutic and harmless makes it difficult to speak openly about harmful aftereffects. Any negative effect is thus attributed to a fault with the person; they used it wrong, misunderstood the 'message', failed to integrate, or have poor disposition for psychological or spiritual development.
The most common symptoms are anxiety, episodes of panic attacks, nightmares, and poor sleep (9). Many describe the reactions as confusing, and the memory from the triggering experience as disjointed and invasive. For some, something difficult has happened along the way, such as being humiliated or ridiculed, while others have experienced a kind of persistent inner nightmare in a waking state. Afterward, some get lost in intense rumination and focus on the meaning of why it went wrong. It feels difficult to accept that it went so badly, or to move on with ordinary life after such an overwhelming event. At the same time, it is difficult to communicate with others about what one has actually experienced. A contributing element is often that the experience was so alien, so existentially confusing, or seemingly supernatural, that one can hardly just set it aside or categorize it with one's other experiences. A common pattern is also a fear that one has inflicted some kind of brain damage or will never be quite oneself again.
Depersonalisering, derealisering og HPPD
Depersonalization, derealization, and HPPD For some, there are persistent changes in conscious experience that linger after the psychedelic experience. This can involve so-called depersonalization and derealization. It's an extremely uncomfortable state of feeling out of touch with one's own body and person, or that the external world no longer feels real. One feels lifeless, alienated, disconnected; as if one mechanically performs actions in a pseudo-reality that has been robbed of its usual meaning. Research projects on negative experiences and effects from psychedelics find depersonalization and derealization (DP/DR) as a common complaint (10). Generally, DP/DR can occur as a reaction to severe stress, traumatic experiences, or other overwhelming circumstances. It is believed that a capacity for mental distancing can be useful in certain critical situations but becomes a problem when it persists beyond the event itself. Here psychedelics may possibly be a trigger due to the very intense and strange experiences, as well as how they acutely change our usual perception of ourselves as persons and the external reality.
An even more distinctive phenomenon is what's called Hallucinogen Persisting Perceptual Disorder (HPPD). It refers to changes in perception, that is, how we perceive reality, that continue long after the experience. Primarily these are visual changes, where one may experience disturbing visual phenomena such as double vision, wavy or melting objects, afterimages, white-grained dotting, frequent changes in size (11). For a closer impression of how this can manifest, examples can be seen here. While many experience mild and transient visual phenomena in the very nearest time after a psychedelic experience, they become very persistent and dominant in HPPD (12). The changes assume such a strong intensity that one can experience function and well-being as significantly reduced. For many, it will be frightening and one can become marked by anxiety for mental health, where also shame and self-blame are common. HPPD often occurs simultaneously with depersonalization/derealization, which collectively gives an unpleasant experience of being trapped in a negatively altered state of consciousness for an indefinite time. This feels isolating in itself and is amplified by the fact that there is little help and understanding to be had among health personnel who are unfamiliar with the problems, or that it is difficult to be open about issues from illegal experimentation.
Severe negative reactions
Probably the most discussed concern with the use of psychedelics is that it can trigger psychoses. That is, a more fundamental break with reality is provoked, either in particularly vulnerable individuals or in persons without particular risk beforehand. Within clinical studies, people with a history of such symptoms or close family with psychotic disorders have so far been excluded. This is based on a lesson from the early research period from 1940-1970. Clinical studies from this period show that people with schizophrenia and bipolar disorder experienced a worsening of symptoms, including persistent psychosis symptoms, suicide attempts, and completed suicides (13). Another important finding is that when healthy parents and healthy siblings of schizophrenic patients were given LSD, 50% experienced psychosis symptoms that lasted up to 6 weeks (14).
There is as yet no consensus on how great this risk really is, but based on the research that has been done, we encourage everyone, and especially those with extra vulnerability factors, to take a precautionary approach with psychedelic substances. In this connection, it is worth mentioning that there is a long academic tradition of identifying similarities between psychedelic and psychotic experiences (15), and that it is not an uncommon issue in acute psychiatric clinics or as reported cases in medical journals (16). The same is probably true for bipolar disorder, where research suggests an increased risk of manic episodes after psychedelics (17).
Fortunately, it is rare, but sometimes dramatic and destructive episodes occur in connection with the intake of psychedelics. This usually concerns serious actions committed during acute confusion, where the inner chaos is acted out or accidents can occur. The horror stories about LSD being like Russian roulette or fatal jumps out of windows in the firm belief of one's own flying skills are definitely exaggerated, but not entirely without basis in real events (9). In a large study on recreational users' most difficult psychedelic experience, 11% reported putting themselves or others in physical danger (8). There are conflicting findings regarding increased suicide risk and the risk of worsening mental disorders (18), where it may be worth noting that influential studies in recent times have controlled for, among other things, a history of depression (19). This makes sense if one wants to clarify if psychedelics themselves are associated with increased risk, but it means we know less about how risky it is for people with greater vulnerability. The truth is nuanced There is probably a complex picture regarding what leads to negative experiences and aftereffects. Personal vulnerability, unfortunate immediate context, lack of preparation, difficult life situations, excessive dosages, mixed use, little social support, and not least outright bad luck are likely important. At the same time, we cannot completely disregard the qualities of the substances themselves. A common feature of both positive and negative psychedelic experiences is that they are destabilizing (20). Usual patterns of self-understanding and perception of reality are broken down, which, for example, can lead to radical shifts in philosophical and religious beliefs (21). Our experience of what is normal, real, and true is challenged (22) – and so are the control strategies that usually keep emotional wounds ‘in check’. The brain and mind are more receptive and susceptible to impressions; the mental filter is less stable, and strong emotions are more accessible both during the experience and afterwards. Such an opening can be for better or for worse. Neuroplasticity (the brain's malleability) is in principle a neutral process, and one should be cautious with assumptions that the substances have inherently good properties. It is also strongly recommended to have a solid dose of common sense and skepticism regarding the flourishing underground market of self-declared therapists, shamans, and radical groupings (23). For more on difficult psychedelic experiences, Ecstatic Integration | Jules Evans | Substack is a very interesting newsletter, covering both new research and theoretical perspectives. Regarding specific conditions, for instance, HPPD is Nonprofit - The Perception Restoration Foundation is a good resource. We therapists at Psykolyse have extensive experience in offering conversations for users who experience negative effects after use, and you can be assured that you can talk to us about your psychedelic use and experiences after use. In addition, we educate healthcare professionals about these topics. In the case of severe negative reactions or sudden worsening of mental condition – such as psychosis, mania, suicidality – we recommend that you contact the emergency room or the acute team at your local DPS.
For more on difficult psychedelic experiences, Ecstatic Integration | Jules Evans | Substack is a very interesting newsletter, covering both new research and theoretical perspectives. Regarding specific conditions, for instance, HPPD is Nonprofit - The Perception Restoration Foundation is a good resource. We therapists at Psykolyse have extensive experience in offering conversations for users who experience negative effects after use, and you can be assured that you can talk to us about your psychedelic use and experiences after use. In addition, we educate healthcare professionals about these topics. In the case of severe negative reactions or sudden worsening of mental condition – such as psychosis, mania, suicidality – we recommend that you contact the emergency room or the acute team at your local psychiatric treatment services.
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