Do Psychedelic Effects Become More or Less Intense With Age?

Sam Woolfe
11 min readApr 15, 2024

I have come across many accounts of psychonauts who say they prefer lower doses of psychedelics as they gain more experience with them. Perhaps this is because, as I’ve discussed before, psychedelics can feel more daunting as you get older. And this can be for several reasons: less fearlessness and risk-taking, more experience with the challenging side of psychedelics, and a greater desire to feel mentally stable and not do anything that might ‘rock the boat’.

However, there is another potential reason that doesn’t have to do with finding psychedelics daunting: dose requirements that change with age. Indeed, I have heard from psychonauts — whether they be educators like PsychedSubstance or those I interact with — who say they can reach the same place with psychedelics but with lower doses. This is a pretty common phenomenon, yet it is quite curious. Why does this kind of change occur? Is there any scientific evidence to validate these anecdotal reports?

I can propose some reasons, and use some metaphors, that can help clarify why many psychonauts notice this kind of change with age, but research is needed to uncover the reality (and mechanisms) of this phenomenon. As we will see, some studies seem to find the opposite holds true, which seems to match other psychonauts’ observations: less intense effects with age.

The Narrow Focus on High Doses

The psychonaut and lecturer Terence McKenna has become well known for recommending other psychedelic explorers to take five grams of dried psilocybin mushrooms in silent darkness. Other psychonauts have since come to repeat this ‘wisdom’ as if it is the superior way of using these compounds.

While taking a strong dose of shrooms in silent darkness, by oneself, has surely led to mystical and transformative experiences for many people, I’m sure it has also led people into some dark places. By ‘dark places’, I don’t just mean challenging experiences someone was able to navigate themselves; I mean unnecessarily intense and prolonged periods of distress they were unable to handle. McKenna’s advice does not include mention of harm reduction factors like music to guide and enhance the experience (as well as help people during difficult periods).

The ‘five grams in silent darkness’ strategy also misses out on protective factors like psychological support (from a trip sitter, guide, therapist, or shaman). The ‘McKenna protocol’ can come across as flippant. It does not take into account personal sensitivity to psychedelics or other personality factors, which can influence the likelihood of someone having a spiritual or challenging experience on a psychedelic.

I think McKenna’s advice can be used in a status- or competition-focused way; it often ignores or overlooks harm reduction considerations in favour of the desire to be the more intrepid or ‘authentic’ psychonaut. This can be a high-risk, high-reward approach to psychedelic use. It may lead to earth-shattering, life-changing experiences, but it can also put people in harm’s way. There are other ways of using psychedelics that are lower risk, and which don’t sacrifice potential benefits.

Experiencing Intense Psychedelic Effects With Low and Moderate Doses

Related to this discussion, the McKenna protocol for tripping leaves out the possibility that some people may be able to experience intense psychedelic effects with a lower dose than someone else, not only because of personality differences but also due to differences in people’s history of psychedelic use.

In other words, someone might not need five grams of shrooms to achieve desirable effects because they find they’ve found, with age, they can get to that place with a (sometimes significantly) lower dose. I should clarify here that it is not necessarily the age gap that determines this, as it is someone’s level of experience. It could be that age itself plays a role in how intense a trip is, but it appears that changes in dose requirements can occur after, say, several years of using psychedelics.

What this means is that whereas before, one might need a strong dose to achieve desired effects like ego dissolution, psychological insight, or emotional catharsis, in later years, these experiences can be had with lower doses. This can be quite surprising, as there are plenty of popular dosage charts that tell you what kind of experience you can expect from a particular dose. Levels of dosage are meant to be correlated with levels of experience. But of course, ‘set and setting’ play important roles, too, and previous experience with psychedelics can be one aspect of ‘set’ (or mindset).

For many people, low or moderate doses of psychedelics can induce profound and meaningful experiences, whereas the strong doses one used to take can start to feel too strong. High doses start to become unnecessarily overwhelming. This can be thought of as an increased sensitivity to psychedelics, which is distinct from people’s inherent, personality-driven sensitivity to these substances.

Perhaps some people still enjoy reaching those maximal states of stimulation and chaos from psychedelics as they get older. Others, however, become more intentional and mindful of what they specifically hope to gain from a psychedelic experience (e.g. insights, healing, personal growth), and if lower doses can deliver this, then they become preferable. There’s no point in increasing the risks of tripping (which happens when you increase the dose) if those greater risks aren’t felt to be matched by greater rewards.

Why Might People Become More Sensitive to Psychedelics With Age?

I’m not the first person to think or say this, of course, but once the ‘doors of perception have been opened’, they stay open, in a sense. This doesn’t mean everything becomes psychedelic in sober life (except in cases of HPPD), but it can mean that it becomes easier to reach a certain kind of headspace or experience when subsequently taking psychedelics.

Mendel Kaelen, a psychedelic researcher at Imperial College London, has likened psychedelic therapeutic action to carving out new paths in the snow. He said:

Think of the brain as a hill covered in snow, and thoughts as sleds gliding down that hill. As one sled after another goes down, it will be drawn into preexisting trails, almost like a magnet. In time it becomes more and more difficult to glide down the hill on any other path or in a different direction. Think of psychedelics as temporarily flattening the snow. The deeply worn trails disappear and suddenly the sled can go in other directions, exploring new landscapes and, literally, creating new pathways.

This carving out of new pathways may translate not just into healthier ways of thinking about oneself, others, and the world — it might also carve neural pathways that are accustomed to the psychedelic state. After all, the more psychedelic experiences you have, the more familiar this state will become. Thus, taking a psychedelic again, even in a low dose, may make it easier to fall into those grooves.

The saying ‘less is more’, then, can start to become very real for experienced psychonauts. However, there may be other reasons why psychonauts require lower doses as they get older. Perhaps they have become more willing or able to let go and surrender, which can lead to more desirable or meaningful experiences. With age, one (hopefully) develops greater wisdom, which can translate into fewer or weaker ego defences, making it easier to give up resistance. This can make all the difference. Whereas before, high doses may have ‘forced’ one into a state of ego dissolution, a moderate dose and a more prepared mindset may achieve the same result.

In addition, as people become more experienced with psychedelics, they may start to more closely heed the wisdom of set and setting, that is, respecting how myriad inner and outer factors can affect the quality of psychedelic experiences. In this way, taking a lower dose in a more prepared set and setting can lead to intense and rich experiences.

Is Increased Sensitivity to Psychedelics a Scientifically Valid Concept?

While in the short term, psychedelics increase one’s tolerance and cross-tolerance (for a few days), in the long term, they might create a kind of reverse tolerance (also known as drug sensitisation). This is a well-known pharmacological phenomenon, describing people’s increased reaction (positive or negative) to a drug following its repeated use. This effect can occur in users of stimulants such as cocaine or amphetamines. On the other hand, this sensitisation does not occur with benzodiazepines, which only exhibit increased tolerance (drug desensitisation, or weakening of effect) with repeated use.

However, I have not come across research showing that psychedelics can lead to reverse tolerance on a pharmacological level. There is, in contrast, plenty of research on how psychedelic compounds cause short-term tolerance. Some misinformation on psychedelic-induced reverse tolerance exists, such as can be found in this psychology textbook. This text for psychology students claims:

One notable feature of hallucinogens is their persistence. Some amount of these drugs may remain in the body for weeks. If an individual ingests the hallucinogen again during this time period, the new dose of the chemical is added to the lingering amount, creating more profound and potentially dangerous effects. This effect is sometimes called reverse tolerance because the second dose may be less than the first but cause the same or greater effects.

However, this is complete misinformation. Trace amounts of a psychedelic may be detectable in urine for 2–3 days, with the drugs detectable in hair for 90 days. But the body does not contain a ‘dose’ of the drug that a new dose is added to, and which can somehow ‘reactivate’ weeks later, thereby creating a stronger-than-expected experience.

Instead, what may occur is reverse tolerance of a psychological kind. As users become more familiar with the altered states of consciousness induced by psychedelics, they can find it easier to enter those states with lower doses. This may be similar to how experienced shamans can enter a psychedelic state with lower doses than those used by most users. In fact, shamans may be able to obtain similar altered states without the use of any drugs at all, instead using methods like repetitive drumming and dancing. Similarly, psychonauts may find it easier to slip into altered states when meditating or doing psychedelic breathwork.

While only speculation at this point, it appears that many psychonauts could need lower doses of psychedelics once they are familiarised with the effects of these compounds. But perhaps what is being referred to as reverse tolerance or increased sensitivity is, in some cases at least, another aspect of set. For example, if you expect a psychedelic experience to be a certain way, then this can increase the likelihood of that type of experience occurring, even if you take a lower dose.

Psychedelic researchers have pointed out this effect of psychedelics (thinking or hoping that something will happen, encouraging that very thing to happen). This can improve treatment outcomes, if this expectation effect is of a positive nature, but it does also mean clinical trial results may be somewhat biased. After all, trial participants (who carry positive or even highly inflated expectations) will know they’re in the drug group once the effects begin to take hold. Once this happens, expectancy effects can help encourage a powerful mystical experience (or perhaps lead to disappointment if such an experience doesn’t occur).

In any case, psychedelics may not cause psychological reverse tolerance but instead create certain expectations in psychonauts, which then influence their subsequent trips. It would be useful, however, to see research into this area. Studies could be carried out that compare the effects of psychedelics for naive users compared to experienced psychonauts. Questionnaires might be used to see what kinds of psychological factors may correlate with differences in subjective intensity between naive and experienced users (if such differences turn out to be statistically significant).

Earlier Trips Often Stand Out as the Most Intense

Despite increased sensitivity to psychedelics over time being a commonly reported phenomenon, there are other reports to the contrary. Many psychonauts find that their initial or earliest trips were the most intense ones. These are the experiences filled with the most elevated levels of novelty, awe, fascination, and shock (on an experiential, existential, and ontological level). This makes sense, of course. The first (or first few) psychedelic experiences are so novel — so unliked what is experienced in sober consciousness — that they cannot help but be intense. While subsequent trips may unearth new perceptual, emotional, and cognitive experiences, and many diverse mindscapes, one may still be desensitised to psychedelia in a general sense.

With age and experience, one gets used to the feeling of having their mind altered in a way that is radically different from sober consciousness. There may also come a point where subsequent trips really do feel repetitive: seeing the same kinds of visuals, having the same insights (which one still needs to integrate), and experiencing similar emotional challenges. One may also experience mystical or spiritual effects that used to feel earth-shattering because of how novel and special they seemed, but which may come to appear less so with repetition. After all, rarity is often psychologically tied to how intense, significant, and memorable an experience is.

The late Anthony Bourdain noted that when he was younger, he used LSD a lot and had very positive experiences with it. These experiences didn’t transform his philosophical views in any grand way, such as bestowing him with some grand unified theory of reality. But what he did find was that it offered him valuable alternate perspectives: “I think it just made me more open-minded. A willingness and even an eagerness to step into other people’s shoes, to look at the world from perspectives other than the ones I was raised with.” He then adds:

That said, I’ve never felt the urge to do it again. I feel that I kind of learned what I had to learn and beyond that it becomes more of a masturbatory experience rather than an enlightening one.

Increased Age May Be Linked to Less Intense Psychedelic Effects

A recent preprint from Hannes Kettner et al. also challenges the notion of increased sensitivity to psychedelics over time. The researchers compared the effects of psychedelics on younger and older adults who attended a guided group psychedelic session in a retreat setting. They found that, compared to younger adults, older adults had less intense trips.

Jacob Aday, an experimental psychologist at the University of Michigan, responded to this particular finding on Twitter, saying, “This is becoming a fairly well-established phenomenon in the psychedelic literature.” He noted a 2021 systematic review he carried out with fellow researchers, which found that “increased age and experience with psychedelics were individual differences related to generally less intense effects, indicating that users may become slightly less sensitive to the effects of the drugs after repeated usage.”

This result was replicated in his more recent study on ayahuasca: “participant age was negatively related to the occurrence of mystical-type experiences and awe, supporting literature indicating blunted psychedelic effects with increased age.” Aday speculates that this is possibly related to decreased 5-HT2AR binding (this is the serotonin receptor that classic psychedelics bind to, which mediates their acute effects). So far, then, it appears that the scientific literature goes against what many psychonauts report anecdotally.

I believe this kind of research is important not just for theoretical reasons but also for practical ones. As already alluded to, there are several factors that can influence people’s responses to psychedelics. What this means is that not everyone requires the same dose in order to obtain desirable states of consciousness. Therefore, if it turns out that previous experience with psychedelics is related to changes in dose preferences, then psychedelic clinics and retreats can take this into account.

Having more personalised plans for psychedelic sessions would be better from a harm reduction standpoint. This would also help people can trip as comfortably as possible and achieve states of consciousness that are desirable and beneficial.

Originally published at on April 15, 2024.



Sam Woolfe

I'm a freelance writer, blogger, and author with interests in philosophy, ethics, psychology, and mental health. Website: