Background: Medication related problems (MRPs), occur due to improper use of prescribed drugs. Patients on antibiotics may experience MRPs from the prescribed antibiotics, omission of prescription of necessary antibiotic or through drug interactions and adverse reactions. There is paucity of local data on MRPs in antibiotic use.

Objectives: This study aimed to investigate the prevalence and types of medication related problems among patients on antibiotics in the medical wards at Kenyatta National Hospital.

Methodology: Cross sectional study design was adopted for this study and patients were recruited from the medical wards between September and November 2018. The Hepler and Strand tool (2012) was used to abstract data and classify the types of MRPs. Analysis was done descriptively and inferentially using STATA version 13.

Results: A total of 94 participants were recruited. Drug-drug interactions (13.8%), improper drug selection (13.8%) and over dosage (12.8%) were the most prevalent MRPs. Marital status (p=0.025), decreased estimated glomerular filtration rate, (p=0.016), use of ceftriaxone (p=0.015), carbapenems (p=0.033) and ceftazidime (p=0.001) were significantly associated with the occurrence of MRPs. Participants who were treated with ceftazidime had a higher odds of experiencing MRPs compared to those who were treated with other antibiotics, OR: 5.62 (95% CI: 1.34,23.5). Participants with a lower eGFR, had a higher odds of experiencing MRPs compared to those who had higher eGFR OR: 5.22 (95% CI: 1.18,23.0).

Conclusion: The prevalence of MRPs was high. Measures should be put in place to address these so as reduce the rising burden of antimicrobial resistance.

Keywords: Medication related problems, Antibiotics, Glomerular filtration rate, Medical wards