The incidence of over-the-counter medication use in patients with midgut neuroendocrine tumors.

Recent increases in the use of over-the-counter (OTC) medicines and the underreporting of the use of these medications to physicians have sparked interest in the number and types of "supportive" therapies used by patients with neuroendocrine tumors (NETS). Patients with NETS are of special interest as a result of the potential interactions/interferences between tumor-associated peptide and amine production and OTC supplements. A prospective analysis of patients with primary small bowel NETS between 1998 and 2012 was conducted to define and catalog each patient's prescription and OTC medication use at each clinic visit. The most recently recorded patient medications were used for this analysis. Three hundred sixty-two patients with small bowel primary NETS were studied. One hundred eighty-seven patients (51.6%) were taking nutritional supplements. Of these taking supplements, the per cent of patients taking one, two, three, or more than three supplements was 28.3, 24.1, 22.5, and 25.1 per cent, respectively. Females (n = 109) were more likely to take supplements in comparison to males (n = 78; P = 0.037). Fifty one patients (14.1%) took proton pump inhibitors and 31 patients (8.6%) took loperamide. OTC supplements were used by 50 per cent of patients with primary small bowel NETS in this study. Over one-third of our patients reported using three or more OTC medicines daily. These medicines have the potential to interact with the metabolism of prescribed medicines, modify ability to clot during surgery, exacerbate NET symptoms, and alter NET markers. Given the prevalence of OTC medications and their potential actions, it is important to carefully catalog their use.