Ibogaine can affect the heart's electrical rhythm, which worries regulators. The FDA may issue formal written safety requirements that anyone using ibogaine in a clinical program must have their heart tested first. This would slow down at least one current ibogaine program by at least 18 months because they'd have to add new testing requirements and get FDA approval for the changes.
FDA has legitimate safety signal basis from QT prolongation and arrhythmia data. However, 'formal guidance' is a specific regulatory action requiring significant institutional process. FDA more commonly issues clinical holds or requests protocol amendments rather than standalone guidance documents on a single compound. A clinical hold or protocol amendment requiring cardiac screening is more likely than formal published guidance. The delay prediction is plausible but the specific mechanism (formal guidance document) is less certain. Confidence reduced from 0.81.