Ginkgo biloba interacts with midazolam
In addition to interacting with midazolam (Versed for sedation and anxiety), researchers from the FDA and the NIH studied ginkgo’s effect on the combination of lopinavir/ritonavir (Kaletra, Aluvia for HIV/AIDS).
But only the midazolam interaction with ginkgo biloba appeared to be significant for patients.
First, the details.
- The effect of 2 weeks of ginkgo biloba treatment was studied in 14 healthy volunteers given lopinavir/ritonavir.
- In addition, single doses of midazolam and fexofenadine (Allegra) were administered prior to and after 4 weeks of ginkgo biloba to assess its influence on CYP3A and P-glycoprotein.
- CYP3A is a drug metabolizing enzyme.
- P-glycoprotein is a cell transport pump, which protects against harmful substances in the body.
And, the results.
- Lopinavir/ritonavir blood levels were not significantly affected by ginkgo biloba.
- However, ginkgo biloba decreased midazolam blood levels relative to the start of the study.
The bottom line?
The results suggest that ginkgo biloba increases the activity of the drug metabolizing enzyme CYP3A, and this lead to lower midazolam blood levels.
There was no change in lopinavir blood levels. This was thought to occur because the ability of ginkgo to increase the activity of CYP3A4 was offset by ritonavir, which is an inhibitor of CYP3A4.
The lopinavir + ritonavir combined product received FDA approval in 2000 for treatment of HIV in adults and children age 6 months or older.
2/15/08 15:37 JR