DMT and ayahuasca

DMT vs ayahuasca: what is the difference?

DMT is a defined chemical. Ayahuasca is a plant decoction whose make-up varies with the species used and how it is prepared [2] [3].

• Plants. The best-known recipe combines the vine Banisteriopsis caapi, which supplies the harmala alkaloids (harmine, harmaline and tetrahydroharmine), with leaves of Psychotria viridis, which supply the DMT [2].
• Why they are combined. Swallowed alone, DMT is broken down by the enzyme MAO in the gut and liver; the harmala alkaloids inhibit MAO-A and let it reach the bloodstream [3] [4].
• Duration. Given intravenously, DMT acts within seconds and wears off within minutes [5]. Ayahuasca takes longer to start and its effects last about four hours [6] [7].
• Risks. Because it contains MAO inhibitors, ayahuasca carries interaction risks that inhaled or injected DMT does not share to the same degree [8].

So findings for one cannot simply be carried over to the other.

How are study sessions run?

Sessions take place in hospital or research settings, after a medical assessment and under continuous supervision.

• Ayahuasca. A single dose in a quiet, dimly lit room with music chosen in advance; investigators close by and a further psychiatric assessment at the end [7].
• Intravenous DMT. An overnight hospital stay, preparation with two therapists the day before, a short infusion with the therapists present, and integration sessions over the following days and weeks [9].
• Medication. Psychiatric medicines are stopped weeks before the session, with a longer gap for MAO inhibitors [9].
• Other forms. Inhaled DMT [8] and continuous infusion, which extends the experience [20], are also being studied.

Which conditions are they being researched in?

Depression is the most researched area, with both ayahuasca and DMT. The studies are still small and short.

In the controlled trials, symptoms improved more than with placebo over the following days and weeks [7] [9]. A secondary analysis also reported less suicidal ideation, which needs confirming [21].

What are the risks and interactions?

In clinical settings, side effects were mostly short-lived. The most serious risk is ayahuasca interacting with antidepressants.

• Ayahuasca. Nausea and vomiting are common [7]; blood pressure may rise slightly [6].
• Intravenous DMT. Pain at the infusion site, nausea, short-lived anxiety and transient rises in blood pressure and heart rate, with no serious adverse events in the trial [9] [15].
• Interactions. Combined with serotonergic antidepressants, the MAO inhibitors in ayahuasca can cause serotonin syndrome, which may be serious [22]. Any medicine or supplement should be reviewed by a doctor.
• Who is left out. Studies exclude people with psychosis or bipolar disorder (personal or family history), pregnancy, significant physical illness or suicide risk; safety in these groups is unknown [7] [9] [23].
• Outside clinical settings. In a large international survey, most people who had drunk ayahuasca reported acute physical effects, mainly vomiting, and a small minority later needed medical care [24]. In a brew prepared outside a study, the make-up is unknown [3].

What is the legal status?

DMT is a controlled substance internationally and in Portugal. No medicine containing DMT or ayahuasca is authorised in the European Union.

• International. DMT is in Schedule I of the 1971 Convention [14] [25]. Plants and brews made from them, such as ayahuasca, are not under international control, but the control board has recommended that governments consider controlling them nationally [26].
• Portugal. DMT is listed in Table II-A of Decree-Law 15/93 [27]. How the law applies to a drink containing DMT is a legal question this page does not settle. Decriminalising personal use does not make the substances legal [28].
• European Union. No medicine containing DMT or ayahuasca is authorised or under evaluation at the European Medicines Agency (checked October 2026) [10].
• Brazil. Religious use of ayahuasca has had its own rules since 2010; this is not a medicines authorisation [29].

What is still being researched

The next studies aim to confirm the early results and answer practical questions.

• Whether the results hold up in larger, longer trials [7] [9].
• How long any benefit lasts [9].
• How much of the effect reflects expectation, since the effects are hard to mask [30].
• What part psychological support plays in the outcome [9].
• Whether what is learnt from pure DMT applies to ayahuasca, whose composition varies [3].
• How both behave in people currently excluded from studies and in those taking other medicines.