Background Chronic myeloid leukaemia (CML) is a chronic myeloproliferative haematological disease that uses tyrosine kinase inhibitors (TKI) as treatment. The patients’ quality of life has improved satisfactorily, however, the use of them bring inherent risks. Drug interactions may compromise the patient’s direct safety which could be undesirable and even irreversible, causing harm to the patient’s health and even leading to death. More knowledge about these drug interactions are important in structuring a specified pharmaceutical service.

Purpose To analyse the potencial drug interactions (PDI) and its factors associated in patients with CML using TKI treated at a university hospital, aimed at improving patient safety.

Material and methods Cross-sectional analytical study with a sample of 101 patients. Data were collected in the patients’ charts and the outcome variable was the presence of PDI, inquired in Micromedex database. Multivariate regression was performed using the Poisson multiple regression model.

Results One-hundred and five PDI were identified with a prevalence of 53.5%. Of the 43 PDI involving TKI, 19 different pairs of drug-drug interactions were observed: 13 (68%) were severe and six (32%) were moderate. The main conduct was therapeutic drug monitoring. The most prevalent pair among the severe ones was Imatinib Mesylate with Domperidone (20%) and among the moderate ones was Imatinib Mesylate with Levothyroxine (50%). The occurrence of PDI has been shown to be associated with female sex, the chronic phase of the disease, the use of Dasatinib and the use of more than five drugs concomitant with TKI.

Conclusion Results revealed a significant number of PDI among patients with CML. In addition, they suggest associated PDI risk factors commonly reported in the literature: chronic disease, female sex and polypharmacy. An important finding was the use of TKI Dasatinib. Most interactions can compromise patient safety, which highlights the importance of this topic and the need to evaluate and monitor the cancer patient’s drug therapy.

Reference and/or acknowledgements Rodrigues A, Cruz A, Marialva M, et al. Clinical pharmacist contribution to profile and manage potential drug interaction in intensive care unit. Euro J Hosp Pharm: Sci Pract 2012;19:226.

No conflict of interest.