Oral antineoplastic agent interactions with medicinal plants and food: an issue to take into account.

Objective: To review interactions between oral antineoplastic agents (OAAs) for the treatment of solid and hematological tumors and common food and medicinal plants.

Materials And Methods: All potential interactions between OAAs, medicinal plants and food were reviewed. OAAs were considered to be drugs for oral administration that have direct antitumor activity and were approved by the European Medicines Agency in April 2015. We performed the literature search in Pubmed(®) considering only medicinal plants and food. In addition, available data were analyzed from each OAA in secondary data sources taken from Thomson Micromedex(®) and Lexi-comp(®), as well as in the summary of product characteristics.

Results: Fifty-eight OAAs were analyzed. We found interactions in 60.3 % of OAAs. Those with most interactions described were: imatinib and procarbazine (4 interactions) and erlotinib, vemurafenib, pomalidomide, medroxyprogesterone and methotrexate (3 interactions).

Medicinal Plants: We found 39 interactions (74.4 % important). St. John's wort was the medicinal plant with most interactions (92.6 % were considered important). The rest were: important (ginseng-imatinib, methotrexate-cola and tobacco-erlotinib and tobacco-pomalidomide) and moderate (caffeine-vemurafenib/medroxyprogesterone, medroxyprogesterone-ruxolitinib/St. John's wort, garlic-anagrelide and ginseng-procarbazine).

Foods: Twenty-six interactions (61.5 % important). Grapefruit had most interactions (82.4 % were considered important). The rest were: important (alcohol-procarbazine) and moderate (dairy-estramustine, methotrexate-ethanol, procarbazine-tyramine, vitamin A-tretinoin/bexarotene and grapefruit-bexarotene/etoposide/sunitinib).

Conclusion: A review of interactions of medicinal plants and food should be taken into account in the management of OAAs, since more than half have interactions with MPs and food, of which 70.3 % are considered important. The most relevant are HSJ, grapefruit, ginseng and tobacco. This review is intended to serve as a support to all healthcare professionals at the time of prescribing or dispensing OAAs.