Potential drug interactions in adults and the older people in the hospital environment





Objective: to determine the prevalence of potentially serious and contraindicated drug interactions in adult and older people patients in public, mixed and private hospital settings. Methods: cross-sectional study with prescriptions for 27,088 patients over 18 years of age, divided into the “Adults” and “Older people” groups, from six public hospitals and five mixed and private hospitals in three regions of Brazil in February 2023. Data were collected from NoHarm platform, a tool used to organize the clinical pharmacist’s work process, and analyzed potential serious and contraindicated drug interactions. Results: a total of 128,143 prescriptions were included in the study, 47.8% from the adults group and 52.2% from the older people group. The presence of at least one potential interaction in the prescription in the total population was 22.3%, being higher in the elderly population (24.5% vs. 19.9%, P < 0.001) in male patients (24.7% vs. 20.2%, P < 0.001), in prescriptions for patients in a 100% public hospital (27.8% vs. 16.1%, P < 0.001) and with a greater number of prescription items (18 vs. 3 items, P < 0.001). The total number of drug interactions found was 71,047, the most prevalent being among psychoactives and drugs that act on the gastrointestinal system, both in the adults group (32.9%) and in the older people group (22.4%). Conclusion: this study identified a high prevalence (22.3%) of drug interactions in hospitalized patients, more prevalent among older people and in public hospitals. The drug classes involved in the interactions varied between the adult and older people groups.


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Organização Mundial da Saúde. Medication Without Harm - WHO Global Patient Safety Challenge. Geneva: WHO; 2017. Disponível em: https://www.who.int/initiatives/medication-without-harm. Acesso em: 13 de maio de 2023.

Instituto para Práticas Seguras no Uso de Medicamentos. Desafio global de segurança do paciente sem danos. Boletim ISMP Brasil; 2018. [acesso em 2023 Mai 12]. Disponível: https://www.ismp-brasil.org/site/wp-content/uploads/2018/02/ISMP_Brasil_Desafio_Global.pdf. Acesso em: 13 de maio de 2023.

Ministério da saúde. Interações medicamentosas: Formulário Terapêutico Nacional. Textos Básicos de Saúde. Brasília (Brasil). 2010. Disponível em: https://bvsms.saude.gov.br/bvs/publicacoes/formulario_terapeutico_nacional_2010.pdf. Acesso em: 29 de março de 2023.

Daunt, R., Curtin, D., & O’Mahony, D. Polypharmacy stewardship: a novel approach to tackle a major public health crisis. The Lancet Healthy Longevity. 2023;4(5):e228-e235. DOI:10.1016/S2666-7568(23)00036-3

Mannucci PM, Nobili A, Pasina L, et al. Polypharmacy in older people: lessons from 10 years of experience with the REPOSI register. Intern Emerg Med. 2018;13:1191-200. DOI: 10.1007/s11739-018-1969-1.

World Health Organization. Medication Safety in Polypharmacy. Geneva: World Health Organization; 2019. (WHO/UHC/SDS/2019.11). Disponível em: https://apps.who.int/iris/bitstream/handle/10665/325454/WHO-UHC-SDS-2019.11-eng.pdf?ua=1

Cahir C, Wallace E, Cummins A, et al. Identifying Adverse Drug Events in Older Community-Dwelling Patients. Ann Fam Med. 2019;17(2):133-140. DOI: 10.1370/afm.2359.

American Geriatrics Society Beers Criteria® Update Expert Panel. American Geriatrics Society 2019 Updated AGS Beers Criteria® for Potentially Inappropriate Medication Use in Older Adults. J Am Geriatr Soc. 2019;67(4):674-694. DOI: 10.1111/jgs.15767.

National Institute for Health and Care Excellence (NICE). Multimorbidity and polypharmacy. 2017. Disponível em: https://www.nice.org.uk/advice/ktt18/chapter/Key-points-from-the-evidence. Acesso em: 29 de março de 2023.

Deguchi M, Nishida K, Enokiya T, et al. Risk factor analysis of the decrease in gait speed among Japanese older outpatients with polypharmacy. J Pharm Health Care Sci. 2019;5:1-18. DOI: 10.1186/s40780-019-0152-4.

Da Silva Pereira GJ, Sette IMF, de Farias Belém L, et al. Estudo de utilização de medicamentos na clínica médica. Rev Bras Farm 2008;89:3.

Correr CJ, Pontarolo R, Ferreira LC, et al. Riscos de problemas relacionados com medicamentos em pacientes de uma instituição geriátrica. Rev Bras Ciênc Farm. 2007;43(1):55-62. DOI: 10.1590/S1516-93322007000100007

Bhagavathula AS, Berhanie A, Tigistu H, et al. Prevalence of potential drug-drug interactions among internal medicine ward in University of Gondar Teaching Hospital, Ethiopia. Asian Pac J Trop Biomed. 2014;4(Suppl1):S204-8. DOI: 10.12980/APJTB.4.2014C1172.

Fattinger K, Roos M, Vergères P, et al. Epidemiology of drug exposure and adverse drug reactions in two Swiss departments of internal medicine. Br J Clin Pharmacol. 2000;49(2):158-167. DOI: 10.1046/j.1365-2125.2000.00132.x

Yamagata AT, Barcelos Júnior RMC, Galato D, et al. Perfil dos estudos de interações medicamentosas potenciais em hospitais brasileiros: revisão integrativa da literatura. Rev Bras Farm Hosp Serv Saúde. 2018;9(4):1-9. DOI: 10.30968/rbfhss.2018.094.003.

ZHENG, Wu Yi et al. Drug-drug interactions and their harmful effects in hospitalized patients: a systematic review and meta-analysis. Eur J Clin Pharmacol. 2018;74:15-27. DOI: /10.1007/s00228-017-2357-5.

Tannenbaum C, Sheehan NL. Understanding and preventing drug–drug and drug–gene interactions. Expert Rev Clin Pharmacol. 2014;7(4):533-544. DOI: 10.1586/17512433.2014.910111.

Sepehri G, Khazaelli P, Dahooie FA, et al. Prevalence of potential drug interactions in an Iranian general hospital. Indian J Pharm Sci. 2012;74(1):75-9. DOI: 10.4103/0250-474X.102548.

CARVALHO, Rhanna Emanuela Fontenele Lima de et al. Prevalência de interações medicamentosas em unidades de terapia intensiva no Brasil. Acta Paul Enferm, 2013; 26: 150-157. DOI: 10.1590/S0103-21002013000200008

Iicif Jr N, Rocha JSY. Study of inequalities in hospital mortality using the Charlson comorbidity index. Rev Saúde Pública, 2004;38:780-786. DOI: 10.1590/S0034-89102004000600005.

PIETRZACKA, Karine Knob et al. Use of antidepressants and potential drug interactions in cancer patients treated at a hospital in the Southern Brazil. Rev Epidemiol Controle Infec. 2021;11(1):19-25. DOI: 10.17058/reci.v1i1.14587

Rodgers JL, Jones J, Bolleddu SI, et al. Cardiovascular Risks Associated with Gender and Aging. J Cardiovasc Dev Dis. 2019;27;6(2):19. DOI: 10.3390/jcdd6020019.

Patel RI, Beckett RD. Evaluation of resources for analyzing drug interactions. J Med Libr Assoc. 2016;104(4):290-295. DOI: 10.3163/1536-5050.104.4.007.

Smithburger PL, Buckley MS, Bejian S, et al. A critical evaluation of clinical decision support for the detection of drug-drug interactions. Expert Opin Drug Saf. 2011;10(6):871-82. DOI: 10.1517/14740338.2011.583916.

Monteith S, Glenn T. A comparison of potential psychiatric drug interactions from six drug interaction database programs. Psychiatry Res, 2019;275:366-372. DOI: 10.1016/j.psychres.2019.03.041



How to Cite

ULBRICH AH, OLIVEIRA JD, COUTO JC, ORTIZ GX, ISOPPO CS. Potential drug interactions in adults and the older people in the hospital environment. Rev Bras Farm Hosp Serv Saude [Internet]. 2023Aug.15 [cited 2023Sep.28];14(3):971. Available from: https://rbfhss.org.br/sbrafh/article/view/971