Assessment of Awareness and Knowledge of Food-Drug Interactions Among Healthcare Professionals and Patients in India

INTRODUCTION

Food-Drug Interactions (FDIs) are defined as situations when food constituents affect the therapeutic efficacy and safety of medications used to treat medical conditions, including when the desired therapeutic response is not achieved at the best drug dosage regimen of a patient who is adherent (Rahman et al., 2022; Vuong et al., 2023). There are several mechanisms by which FDIs occur, such as gastrointestinal physiology changes following food intake, changes in drug dissolution, and effects on drug metabolizing enzymes and transporters (Deng et al., 2017). These changes may lead to delayed, decreased, or increased absorption of drugs, especially when the margin for error is small (Koziolek et al., 2019; Tsume et al., 2023; Choi et al., 2017). This is true of chronic conditions like hypertension, anticoagulant therapy, cancer, and organ transplantation (Rahman et al., 2022). Studies have proven that certain patient groups, i.e., the elderly, recipients of several drugs, and patients suffering from certain illnesses, appear to have an increased risk of suffering from adverse FDI (Vranckx et al., 2018; Petric et al., 2020, Veerman et al., 2020). In past studies, inadequate knowledge about FDIs by patients and Healthcare Professionals (HCPs), including pharmacists, nurses, and physicians, have been reported (Beirão et al., 2025; Kuźbicka et al., 2024). Although these HCPs show awareness about the usual interactive phenomena, knowledge gaps exist about less obvious and newly developing FDIs (Elshenawi et al., 2020; Zaidi et al., 2021). Patient-related issues, like education level and exposure to healthcare, also contributed to awareness and practice (Zawiah et al., 2020; Radwan et al., 2018). Despite the clinical importance of FDIs, studies assessing these in terms of awareness among patients as well as HCPs in Indian clinical settings are very few. Hence, this study aimed to assess the level of FDI-related awareness, doubts and knowledge among HCPs as well as patients, along with associated factors.

MATERIALS AND METHODS

Study design, Study participants and Sample size

An observational cross-sectional design, conducted over a period of six months. The required sample size was determined based on a conventional formula for cross-sectional design studies, considering a confidence level of 95% and precision level of 5%. Consequently, it was determined that the study design required at least 1,000 participants for sufficient statistical power to support the analysis, as suggested by (Bujang, 2021). A total of 1,011 participants, comprising 781 patients and 230 healthcare professionals, were included in STROBE flow diagram (Figure 1).

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Questionnaire Validation and Pilot Testing

Questionnaires for patients and HCPs were adapted from a previously published article and were pre-tested for validity by conducting face-validity with the aid of experts in the department of medical education (Benni et al., 2012). A pilot study was carried out to check the clarity of questions, and modifications were made according to the feedback from the pilot testing. The linguistic expert checked the Marathi translations to ensure accuracy.

Data Analysis

The Statistical Package for the Social Sciences (SPSS) version 25 was used for data analysis. Descriptive statistics were used to summarize the data. Association between categorical variables were assessed using the Chi-square test. All statistical tests were two-tailed and a p-value≤0.05 was considered statistically significant.

Ethical Considerations

The study was approved and reviewed by the Institutional Ethics Committee of Deenanath Mangeshkar Hospital and Research Centre (PharmD_2024_Sept_NS_18; dated 14 Oct 2024). The study was conducted in accordance with the Helsinki Declaration and its subsequent amendments. All the participants gave informed consent prior to conducting the study.

RESULTS

Participant demographics

A total o1f 1011 participants were included, comprising 781 patients aged ≥50 years with almost equal distribution of males (50.3%) and females (49.7%). Among 230 HCPs, the largest population belonged to the pharmacy practice department followed by general medicine and pediatrics. Most HCPs had 0-4 years of professional experience and nearly half of them held post-graduate qualifications (Table 1).

Knowledge level among participants

The association between patient characteristics and knowledge of food-drug interactions showed age, education level, healthcare-related occupation, and family healthcare exposure were significantly associated with knowledge level. Gender (p=0.088) and presence of chronic disease (p=0.095) were not significant associated with knowledge level (Table 2).

Pharmacy practice demonstrated the highest mean knowledge score among departments followed by pediatrics and general medicine whereas community practice and orthopedics showed comparatively lower scores (Figure 2). Similarly, clinical pharmacists and interns exhibited higher mean knowledge compared with doctors, while nurses showed lower mean knowledge scores (Figure 3). Knowledge scores also increased with higher educational attainment with postgraduates demonstrating higher mean scores compared with graduates and diploma holders (Figure 4).

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Among healthcare professionals, the department of pharmacy practice was significantly associated with knowledge level, but not years of experience. Clinical pharmacists, postgraduates, and interns scored higher, while nurses and diploma holders scored lower (Table 3). Having a family member working in healthcare was also significantly associated with better knowledge (OR= 2.213, p=0.001). Clinical pharmacists and interns demonstrated higher odds of good knowledge compared with doctors, although these findings did not reach statistical significance (Table 4).

DISCUSSION

This study highlights persistent gaps in awareness and knowledge of food-drug interactions (FDIs) among both patients and HCPs. Among patients, demographic factors such as age, education, occupation, and family involvement in healthcare were significantly associated with FDI knowledge, consistent with prior findings that education and occupational background influence awareness (Osuala et al., 2021). However, unlike earlier reports linking chronic disease status to higher awareness (Zaidi et al., 2021), our study found no such association. In contrast, research from eThekwini reported no significant relationship between patient demographics and FDI knowledge (Osuala et al., 2022). For HCPs, professional role, training level, years of practice, and departmental setting shaped knowledge, whereas earlier studies suggested that age, gender, and experience were not predictive (Couris et al., 2000). Patient perceptions of drug timing and treatment outcomes also enhanced understanding, aligning with practice-based habits reported in South Africa (Elajez et al., 2024). Awareness among patients remained limited, with fewer than half recognizing common FDIs such as drug-caffeine interactions, and only 71% aware of warfarin-cranberry juice interactions (Meng et al., 2018). Among HCPs, clinical pharmacists scored highest, followed by interns, Doctors and other cadres, while nurses demonstrated the lowest knowledge levels. These findings mirror previous reports of nurses competence in drug-food timing for common medications but gaps in less frequent interactions (Afrooz et al., 2017; Balaban et al., 2025). Pharmacists consistently showed strong knowledge of warfarin-vitamin K interactions, whereas physicians and nurses struggled with identifying less obvious dietary sources (Couris et al., 2000; Khong et al., 2024). Prior literature indicates that only one-third of HCPs possess comprehensive FDI knowledge, with notable deficiencies in administration timing, directly impacting patient safety and therapeutic outcomes (Koziolek et al., 2019). Senior academic staff generally demonstrated greater mastery compared to postgraduate trainees and interns (Benni et al., 2012; Osuala et al., 2022; Khong et al., 2024).

Overall, our findings reinforce the need for structured educational interventions and integration of FDI training into clinical practice. As emphasized in prior studies, targeted strategies are essential to strengthen decision-making and reduce preventable FDIs (Balaban et al., 2025; Khong et al., 2024).

CONCLUSION

The study revealed a poor level of knowledge regarding FDIs among patients and professionals. Although pharmacists had a high level of knowledge, a knowledge deficit was noted among other professional groups and patients. The study verifies the importance of education on FDIs and the need to provide tools to address FDIs to promote a safe drug regimen.