Abstract Introduction Chronic non-cancer pain (CNCP) affects 22–88% of older adults and is associated with a lower quality of life and polypharmacy. It thus puts these already very vulnerable patients at a greater risk of medication-related harm. Aim This feasibility study aimed to implement a multimodal clinical pharmacy intervention to improve CNCP-related care for older adult inpatients on hospital geriatrics wards. Method We conducted a single-arm feasibility study from January to May 2025, including patients aged 65 or older, hospitalised on the geriatrics ward of a tertiary hospital in Switzerland and previously diagnosed with CNCP. Feasibility was defined as the ability to perform the intervention as planned and approximated by recruitment and dropout rates. The intervention included semi-structured interviews about patients’ pain histories, collected patient-reported outcome measures (PROMs) and recorded therapy goals. Pharmacists then conducted medication reviews using a previously developed and validated trigger tool. The trigger tool was used as a standardised approach for identifying medication-related issues, comprising a set of previously validated quality indicators. Findings were discussed during interprofessional ward rounds. Final treatment decisions were made jointly with patients. We followed up with patients by telephone one month after hospital discharge. Results Of 253 screened patients, we included 48 patients: 28 (58%) were interviewed, and 18 (38%) had a follow-up telephone call. Pharmacists suggested 56 therapy changes, with 29 identified by the trigger tool and 27 identified by regular medication review. Therapy change acceptance rates by the care team were 78% and 41%, respectively. Pain frequency and the highest and lowest pain levels over the last seven days all decreased after hospital discharge, although these changes cannot be causally attributed to the intervention. Other pain-related PROMs showed no change or just a slight improvement or deterioration. Conclusion The present feasibility study showed that implementing a clinical pharmacy intervention for older adult inpatients was indeed feasible. However, the recruitment rates were relatively low, and dropout rates were relatively high. Using a standardised approach involving a trigger tool showed promising results for detecting medication-related problems. These are important first indicators that including pharmacists more closely in standard care could be beneficial to CNCP patients.