We appreciate Dr. Flanagan calling attention to a potentially important interaction between some orally administered medications and grapefruit juice. While outside the scope of the workshop reported on in our JADA article, practitioners who administer drugs that interact with grapefruit juice should be cognizant of the potential for more pronounced effects from inhibition of drug metabolism by the hepatic cytochrome pathway.
The potential for a clinically relevant interaction between orally administered triazolam and grapefruit juice is described by Dr. Flanagan1 and may be more pronounced for sublingual administration. He recommends that dental patients who will be sedated with oral medications such as midazolam, triazolam and diazepam should avoid grapefruit for at least two days before sedation.
Previous reports have demonstrated that sublingually administered triazolam results in greater peak plasma levels than does orally administered triazolam,2,3 resulting in greater central nervous system (CNS) effects from the drug.
A study in healthy volunteers reported a 1.5-fold increase in mean triazolam levels in the circulation, delayed the time to peak time of triazolam from 1.6 to 2.5 hours and increased CNS effects of a 0.25 milligram dose administered with grapefruit juice.4 Given the potential for even greater levels of sedation for triazolam when administered sublingually to patients who have recently ingested grapefruit juice, less predictable time to peak blood levels and enhanced CNS depression, dentists should avoid elective oral or sublingual sedation with a benzodiazepine in patients who have recently consumed grapefruit juice.