Macrodosing to microdosing with psychedelics: Clinical, social, and cultural perspectives

Microdosing psychedelics and the risk of cardiac fibrosis and valvulopathy: Comparison to known cardiotoxins

Though microdosing psychedelics has become increasingly popular, its long-term effects on cardiac health remain unknown. Microdosing most commonly involves ingesting sub-threshold doses of lysergic acid diethylamide (LSD), psilocybin, or other psychedelic drugs 2-4 times a week for at least several weeks, but potentially months or years. Concerningly, both LSD and psilocybin share structural similarities with medications which raise the risk of cardiac fibrosis and valvulopathy when taken regularly, including methysergide, pergolide, and fenfluramine. 3,4-Methylenedioxymethamphetamine, which is also reportedly used for microdosing, is likewise associated with heart valve damage when taken chronically. In this review, we evaluate the evidence that microdosing LSD, psilocybin, and other psychedelics for several months or more could raise the risk of cardiac fibrosis. We discuss the relationship between drug-induced cardiac fibrosis and the 5-HT2B receptor, and we make recommendations for evaluating the safety of microdosing psychedelics in future studies.

Culture, context, and ethics in the therapeutic use of hallucinogens: Psychedelics as active super-placebos?

Following decades of prohibition and widespread concern about their mind-altering properties, there is increasing public, scholarly, and clinical interest in the therapeutic potential of psychedelic substances. Serotonergic substances in particular (DMT, psilocybin, and LSD) are now being tested as treatments for such ailments as depression, anxiety, and substance use disorder. This thematic issue of Transcultural Psychiatry presents articles that investigate the cultural assumptions, political dimensions, and clinical and ethical implications that arise from this renewed interest. After reviewing ongoing debates on therapeutic mechanisms of action and the importance of context, we argue that psychedelics can be conceptualized as "active super-placebos"-that is, substances that enhance ritual, symbolic, and interpersonal therapeutic processes by increasing suggestibility and the influence of extra-pharmacological, "non-specific" factors. Rather than simply freeing up habitual constraints on perception, the articles in this issue support the claim that psychedelic encounters typically entail processes of sense-making, crystallization of meaning, and enculturation into contextually mediated assumptive worlds (or ideologies) and behaviours that necessarily install novel constraints with potentially maladaptive consequences. We highlight the importance of clinical and epistemic integrity in the framing of psychedelic therapies. The importance of structuring and providing oversight for the therapeutic context raises difficult questions about the search for appropriate forms of epistemic authority that are at once respectful of the plural cultural origins of psychedelic rituals and mindful of best practices and standards in clinical care.

Microdosing with classical psychedelics: Research trajectories and practical considerations

Microdosing-the intermittent ingestion of minute, sub-hallucinogenic amounts of psychedelic substances, repeatedly and over time-has become a widespread, albeit largely understudied, phenomenon. Regulations around using psychedelics at any dose-micro, mini, macro, or mega-pose all sorts of difficulties for those who wish to systematically study the effects of Schedule I drugs, especially in the United States. Microdosers commonly claim that taking a sub-hallucinogenic (pre-hallucinogenic or sub-perceptual) dose improves higher brain functions, including creativity, productivity, and mood. If true, these results would provide an important experimental edge in distinguishing psychosocial effects (e.g. caused by expectation) from those related to the active psychedelic ingredient. In this critical integrative synthesis, we explore the psychobiological science of dose amounts and how it informs microdosing with classical psychedelics (e.g. lysergic acid diethylamide [LSD] and psilocybin) to highlight and fuel research into questions (e.g. in cognitive neuroscience, consciousness studies, and metacognition). We sketch the hurdle-laden regulatory landscape and the procedures that shroud research with Schedule I drugs. Finally, we offer some future directions relevant to both scholars and clinicians in the social and behavioral sciences as well as in mental health and neurological science.