PPGx is a curated scientific knowledgebase focused on psychedelic pharmacology and pharmacogenomics. It provides information on drug-drug and drug-gene interactions and pharmacology-informed predictions. It integrates evidence from human studies (priority) and other relevant pharmacology evidence to support research and education. The database links psychedelics, conventional medicines, metabolic enzymes, transporters and receptors, highlighting mechanisms of action, interaction risks and genotype-informed variability where available. Evidence is transparently sourced, summarised and graded to allow users to assess both strength and limitations of the data. PPGx is designed for researchers, clinicians and students seeking a structured, evidence-based overview of psychedelic drug-drug and drug-gene interactions, with the long-term aim of supporting the development of precision-medicine approaches in the field.