Kidney transplant patients use several medications, which increases the risk of developing drug-related problems. This is a pre-post-intervention study, carried out in a transplant outpatient clinic in Belo Horizonte, Minas Gerais, Brazil, with post-transplant patients using tacrolimus. Pharmacy consultations were carried out in individual offices, and the initial and final status were measured between the first and the last consultation. Satisfaction with the pharmaceutical service was also assessed. Thirty-nine drug-related problems were identified, 64.3% of patients presenting at least one, of which 79.5% were resolved (p<0.001). The most frequent were “use of unnecessary medications” (26.5%), with omeprazole being the most prescribed medication for this situation. Polymedicated patients had more drug-related problems (p = 0.001). 49 interventions were performed, 51.02% were accepted. The most accepted interventions were recommendations for guidelines regarding the time of administration and reduction of adverse drug reactions (100%) and suspension of treatment (92.3%). In the end, the proportion of patients with stable clinical status increased from 35 .7% to 83.3% (p<0.001). Patients related the pharmaceutical service as very good, reporting the desire for its continuity. Comprehensive medication management positively impacted the patient's clinical situation, proved to be effective in solving drug-related problems, and was very well evaluated by the patients. It is recommended that polymedication is a priority criterion for this service.