Related Experiment Video
Updated: Jun 2, 2026

High-throughput Identification of Synergistic Drug Combinations by the Overlap2 Method
Published on: May 21, 2018
[Drug interactions with grapefruit]
Zoran Z Bojanić1, Novica Z Bojanić, Vladmila V Bojanić
1Institut za farmakologiju i toksikologiju, Medicinski fakultet, Nis. bojaniczoran@gmail.com
Introduction:
The concentration of many orally given medications may be affected by grapefruit or grapefruit juice consumption. It may result in numerous harmful effects.
Interaction Of Grapefruit With Drugs:
Taking only one cup of juice may induce interactions with different drugs even during the period of a few days. The effect is induced by suppression of cytochrome P450 isoenzyme CYP3A4 in the intestinal wall. The Latin name of grapefruit, Citrus paradisi, is quite opposite to the effects which could be induced by taking grapefruit and some medications at the same time. It is necessary to avoid taking grapefruit with the drugs whose pharmacokinetics could be altered by the active principles found in that fruit.
Discussion:
The coloured grapefruit contains less furanocoumarins, but there is no difference in induction and intensity of pharmacokinetic interaction with drugs related to its colour. Other citrus fruits (orange, lemon) do not have such effects, but some other fruits (pomegranate, stella fruit, banpeiyu, hassaku, takaoka-buntan and kinkan) exert inhibitory effects on the activity of cytochrome P450 isoenzyme.
Related Concept Videos
Pharmacokinetics: Drug–Food and Drug–Viral Interactions
Drug toxicity: Drug–Drug Interaction
Pharmacokinetics: Drug–Drug Interactions
Factors Affecting Protein-Drug Binding: Drug Interactions
Displacement interactions can have varying outcomes, ranging from toxicity to virtually...
Combined Effects of Drugs: Synergism
Such synergistic combinations...
Combined Effects of Drugs: Antagonism
The most common type is receptor antagonism, where one drug acts as an antagonist to block the effects of another drug by...

