Throughout medical history, scientists have often overlooked women’s biology. They ignored how menstruation, reproduction, and menopause might affect—or be affected by—drugs.

Until 1993, women were not even required in clinical trials. That changed with the National Institutes of Health Revitalization Act, which mandated their inclusion.

Psychedelic research has made major advances in healthcare and therapy. Yet when it comes to women’s unique needs, the field mirrors the rest of medical research—we still know very little about how psychedelics interact with women’s biology.

Hormonal Influence on Psychedelic Effects

Beyond their psychological impact, psychedelics may be influenced by the menstrual cycle. Hormones could change the strength and quality of the experience.

Classical psychedelics—such as LSD, psilocybin, and DMT—bind to 5-HT2A receptors, which normally respond to serotonin. In the 1990s, rodent studies showed that oestrogen increased the number of 5-HT2A receptors in the brain. Later research found that impaired oestrogen signalling reduced 5-HT2A activity.

Because 5-HT2A activity drives many psychedelic effects, high oestrogen levels may make experiences more intense. This means menstrual cycle phases could matter when determining dosage.

Synergy Between Hormones and Psychedelics

The interaction doesn’t stop there. Oestrogen and progesterone may work together with psychedelics to shape brain activity.

Both high levels of these hormones and psychedelics increase communication between the brain’s hemispheres. This could amplify psychoactive effects.

Oestrogen also boosts dopamine synthesis and function. Since dopamine influences psychedelic effects—especially with LSD—hormone shifts could change the experience by altering the dopamine system.

Psychedelics’ Impact on Hormones

The relationship works both ways. Psychedelics may also change hormone levels.

One study found that blocking 5-HT2A reduced the release of luteinizing hormone-releasing hormone (LHRH), which regulates ovulation and reproductive hormones. By activating 5-HT2A, psychedelics might boost LHRH release.

Psychedelics can also affect stress hormones like prolactin and cortisol. These hormones suppress reproductive function and can disrupt menstrual cycles. Effects may vary by substance:

• Psilocybin lowered prolactin in healthy volunteers.

• LSD raised prolactin in cells by activating certain dopamine receptors.

Since high stress hormones are linked to irregular or absent periods, psychedelics that lower prolactin and cortisol could help prevent—or even reverse—these conditions.

The Need for Women-Specific Psychedelic Research

Understanding this two-way interaction between psychedelics and hormones is critical. It could influence public health and the future of psychedelic therapy.

At Hystelica, we are addressing this gap. We partner with clinical and observational trials to collect women-specific data—covering menstruation, hormone cycles, and beyond.