Do we know that jabara is a Japanese citrus that is similar to yuzu and is consumed as an anti-allergic functional food in Japan and worldwide?
We have previously discussed how grapefruit juice interacts with medications (drugs). A question arises: does jabara also interact with drugs?
Guess what? It has been shown that narirutin in jabara is a ‘paradoxical’ inhibitor of both small intestinal uptake transporters (OATP1A2 and OATP2B1) and efflux transporter (Pgp) yet jabara juice itself is an inhibitor of Pgp! FYI, uptake transporter brings drug into our body while efflux transporter kicks the drug back to the intestinal lumen.
A logical question arises: If a drug (e.g antihistamine fexofenadine) is a substrate of both small intestinal OATP uptake and Pgp efflux transporters, what will happen to its systemic absorption when jabara juice is co-administered?
It has been shown that the inhibition of jabara juice against Pgp supersedes narirutin’s inhibition of OATPs. Consequently, there is an increase in absorption and systemic exposure of fexofenadine in mice (AUC is increased 1.8-fold).
Is this the end of the interaction story implicating jabara?
Not really! It has been further reported that hepta- and hexa-methoxyflavone in jabara juice yields time-dependent inhibition of CYP3A4!
Taken together, what are the implications guys?
This means that for drugs that are both substrate of Pgp and CYP3A4 (e.g. selected protease inhibitors, calcium channel blockers, statins, immunosuppressants, benzodiazepines, anticancer agents, antibiotics and antifungals), the oral absorption, bioavailability (F) and systemic exposure (AUC) of these drugs may increase when co-administered with jabara juice. An increase in exposure may lead to concentration-dependent adverse effects!
Next time when we wish to take jabara juice leisurely or as an anti-allergic functional food, please ENSURE that we are not taking drugs that are substrate of Pgp and CYP3A4! If unsure, please ask our friendly pharmacists or doctors!
Read also:
- Food-Drug Interactions on Drug Safety & Efficacy
- Dietary Reference Intakes for Vitamin C (Ascorbic Acid)
Resource Person: Eric Chan, PhD