Investigation of drug interactions in oncology patients

Cancer patients use many different drugs along with chemotherapy drugs; this leads to drug-drug interactions that increase morbidity and mortality (2,3). In two of the drug-drug interaction studies, it was concluded that 27-58% of all patients receiving chemotherapy treatment had at least one drug-drug interaction (3,5). In this thesis, based on the studies on drug interaction worldwide and in our country, drug-drug interactions in oncology patients will be examined, contribution will be made to studies on behalf of our country, and awareness will be raised on drug-drug interactions. The files of 250 patients who received cancer treatment in the Medical Oncology Department were retrospectively analyzed with Medscape and Drugs.com online databases in terms of drug interactions. 55.6% of the patients are male and 44.4% are female. According to Medscape and Drugs.com, the number of patients with drug interactions is; 223 (85.2%); 238 (95.2%). According to Medscape and Drugs.com, the number and rate of patients with major interactions in these interactions is 28 (11.2%), 67 (26.8%), respectively. A total of 99 drug pairs prolong the QT interval. According to Medscape; A total of 298 QT prolonging drug interaction pairs were observed in 77 patients in 52 (20.8%) patients and in 136 (54.4%) patients on Drugs.com. Chemotherapeutics (Cisplatin, doxorubicin), granisetron, tramadol and antidepressants (escitalopram, citalopram) are the most common drugs that cause major interactions. Granisetron, Oxaliplatin, Doxorubicin, Omeprazole, lansoprazole, famotidine, Escitalopram, citalopram, 63 Foromoterol, albuterol, Hydrochlorothiazide, furosemide, indapamide, Alfuzosin, nebivolol and tramadol are common drugs that prolong the QT distance. While prescribing these drugs, they should be carefully examined in terms of drug interaction. One of the important limitations of our study is that it is retrospective. It has been a preliminary study for a prospective, multi-center study that can be intervened in therapy, can be followed up and will be designed by reaching a wider patient population. Keywords: Oncology, Drug Interaction, QT