Management of concomitant medication interactions

The manuals converge on the need for a structured review of concomitant medicines and related substances before and during psychedelic treatment. Across the extracts, they emphasise checking prescribed, over the counter, herbal, supplement, and rescue medication use, documenting changes over time, and using this information to protect safety and study integrity.

Several sources also agree that medication compatibility matters because some agents may increase risk, alter psychedelic effects, or confound outcomes, so review is tied to screening, session preparation, and ongoing monitoring. They also overlap on specific interaction concerns, especially serotonergic agents and the risk of serotonin syndrome or serotonin toxicity. The psilocybin and LSD protocols both name serotonergic medicines as restricted or potentially exclusionary, and the psilocybin studies add washout or taper timing, including a minimum 5 half-life washout for intermittent or PRN serotonergic agents in one protocol. The ibogaine case report differs somewhat in focus, placing more weight on avoiding additive cardiac risk from other QTc-prolonging substances, while the MDMA study gives broader operational detail about confirming medication data, reviewing changes before each experimental session, and documenting medicines used for adverse events or withdrawal effects.

Sources differ most in the drug classes they foreground.