I am not sure where these numbers came from, but in all my pharmacology training, every study that has been reviewed has show miniscule elevations for psych meds with normal grapefruit ingestion. I have never met a pharmacologist or psychiatrist who worries about grapefruit. I guess I would only worry about this if someone started a new med that was heavy on 3A4, and the person was just starting a grapefruit diet. The problem with stable kinetics and dynamics studies of any sort is that they are invitro and do not account for the incredible dynamics of a living system. Someone who eats grapefruit for breakfast daily will have upregulated prodiction of the needed enzymes, which will increase clearance of grapefruit and allow for equilibrium if another med or substance needs those enzymes.