Cardiovascular Risks

Urgent help first

Chest pain, fainting, a racing or irregular heartbeat, severe shortness of breath, a seizure or collapse are emergencies. In the US call 911. For a possible poisoning, Poison Help is 1-800-222-1222 (see poisoning: what to do first). This page is education only and never advises starting, stopping or changing a medicine.

The short answer

The heart risks of psychedelic and related substances are substance-specific. Classic psychedelics such as psilocybin raise blood pressure and heart rate temporarily. Esketamine does too, and its label sets out who should not receive it. Ibogaine is different: it has been linked to a heart-rhythm problem called QT prolongation and to deaths. Evidence labels used: approved medicine, established, mixed, insufficient evidence, evidence of harm.

Classic psychedelics (psilocybin and relatives)

NIDA lists high blood pressure and rapid heartbeat among short-term effects of these drugs. [1] A 2026 narrative review of psilocybin found that in supervised studies pooled blood pressure rose by about 19.0 mmHg (systolic) and 8.7 mmHg (diastolic), most clearly 60 to 90 minutes after dosing and generally settling within 4 to 6 hours. Serious acute cardiovascular events were uncommon in selected participants, and average QTc effects at standard exposure were small. A valve-damage concern linked to serotonin 2B receptors remains biologically plausible with chronic exposure, but clinical valve injury has not been established. The review stresses that trial participants are medically selected and monitored, and that mushroom products can vary in active content by more than an order of magnitude, so it does not support general cardiovascular reassurance. [2]

A 2025 review groups the risks into three areas: electrical effects and arrhythmia, structural effects and valve disease, and vascular effects including high blood pressure and reduced blood flow. It calls for studies in people with existing heart disease, on drug interactions, and on repeated long-term exposure including microdosing. [3] Label: established for temporary blood pressure rise; insufficient evidence for people with heart disease and for repeated exposure.

DMT

A 2025 review of five early-phase trials in healthy volunteers and people with depression reported that intravenous trials showed systolic blood pressure rises of up to 25.7% and heart-rate increases at higher doses, resolving quickly, with no serious adverse events. The trials were few and mostly in healthy volunteers. [4]

Esketamine (Spravato) and ketamine

The US label for esketamine says it raises systolic and/or diastolic blood pressure at all recommended doses, with a peak about 40 minutes after administration and lasting about 4 hours. In the first 1.5 hours after a dose, 3% to 19% of treated patients and 1% to 4% of placebo patients had a rise of at least 40 mmHg systolic and/or 25 mmHg diastolic at least once in the first 4 weeks. It is contraindicated where a rise in blood pressure or pressure inside the skull poses a serious risk, such as aneurysmal vascular disease. [5] Label: approved medicine (US FDA). NIDA also says ketamine may change blood pressure and heart rate. [6]

MDMA

MDMA is an entactogen, not a classic psychedelic. A systematic review of supervised treatment studies found one serious adverse event: an increase in premature ventricular contractions during MDMA administration that needed brief hospitalization. [7]

Ibogaine: QT prolongation and arrhythmia

Ibogaine is a compound from the West African shrub Tabernanthe iboga; it is not the same thing as the whole plant or traditional preparations, which have their own pages. See ibogaine. The UK poison-service paper cited below says it is not licensed in the UK; its US regulatory status was not verified for this page.

• A toxicology review identified 27 reported deaths after ibogaine and eight case reports suggesting it caused ventricular tachyarrhythmias (dangerous fast rhythms from the heart's lower chambers). Its main breakdown product, noribogaine, stays at clinically relevant levels for days. [8]
• A review of 19 deaths between 1.5 and 76 hours after taking ibogaine found that advanced pre-existing conditions, mainly cardiovascular, and/or other commonly abused substances explained or contributed to death in 12 of the 14 cases with adequate postmortem data. [9]
• UK poison service data (2012 to 2022) covered seven patients. Six showed features of cardiotoxicity, including cardiac arrest, torsade de pointes and QT prolongation, and the authors note it is not licensed in the UK. [10]
• A case report described QTc prolongation and torsade de pointes after ibogaine bought from an internet supplier. [11] Another measured a QTc of 647 ms with several arrhythmias, and QTc prolongation lasting 12 days, long after ibogaine levels were low. [12]
• In 14 people with opioid use disorder given ibogaine in a study, how fast the body cleared it varied greatly and was strongly related to CYP2D6 genotype (a liver enzyme gene), and QTc prolongation tracked ibogaine blood levels. [13]
• A 2026 review says these events are rare but clinically significant, occurred at therapeutic doses and in people without known heart disease, and recommends that any future ibogaine treatment occur only under medical supervision with CYP2D6 genotyping and cardiac monitoring. [14]

Label: evidence of harm (case reports, poison data, toxicology reviews). Because reports mix settings, products and other substances, the real frequency is unknown.

Next steps

Anyone with heart or blood pressure conditions, or who takes heart-active medicines, should talk with a clinician: existing conditions and talking with a health professional. See also iboga vs ibogaine.