Frequency Of Potential Drug-drug Interactions Research Articles

Determination of drug-drug interaction in breast cancer patients receiving doxorubicin and cyclophosphamide regimen.

Drug interactions constitute a significant issue in cancer treatment. Therefore, it is important to assess and analyze all cancer patients' therapies prior to the initiation of chemotherapy. A retrospective observational study was conducted at the Near East University Hospital Oncology Department located in North Cyprus between June 2019 and December 2021. The aim of the study was to determine the nature, type, and frequency of potential drug-drug interactions in breast cancer patients receiving a doxorubicin and cyclophosphamide regimen using Drugs.com, Lexicomp, and Micromedex databases while comparing the three electronic databases, according to the frequency, mechanism, and severity of drug-drug interactions. The study included 40 patients (44.4%) out of 90 patients diagnosed with breast cancer, as 50 patients (55.6%) who did not match the criteria were excluded. According to the Lexicomp database, 12 patients (30%) with breast cancer had 14 potential drug-drug interactions, according to the Drugs.com database, 15 patients (37.5%) with breast cancer had 22 potential drug-drug interactions, and according to the Micromedex database, 13 patients (32.5%) with breast cancer had 15 potential drug-drug interactions. Pearson correlation indicated a weak association (Lexicomp: r = 0.475, p = 0.002 and Micromedex: r = 0.491, p = 0.001) and a moderate association (Drugs.com: r = 0.500, p = 0.001) between potential drug-drug interactions and five or more medications. This study showed that the Drugs.com database detected more potential drug interactions between chemotherapy and nonchemotherapy than the Lexicomp and Micromedex databases. Comprehensive drug review, use of electronic health record systems, and collaboration between healthcare providers such as pharmacists and physicians may be necessary strategies to minimize potential drug-drug interactions and optimize cancer treatment in patients with breast cancer.

Incidence, Patterns, and Severity of Potential Drug Interactions Among Cancer Patients on Chemotherapy in a Tertiary Care Hospital

Objective To study the incidence of potential drug−drug interactions (DDIs) and evaluate their pattern and severity in cancer inpatients. Materials and Methods A detailed clinical data and prescriptions of 150 inpatients with different malignancies were subjected to DDI screening using Micromedex software. The frequency of potential DDIs and their types, patterns, and severity were investigated. Results A total of 360 potential DDIs were present in 111 (74%) of 150 inpatients, dominated by female (67.33%) and breast cancer (30%) patients. The incidence of severe interactions was 63.88%, moderate interactions 35.83%, and mild interactions 0.27%. The potential mechanisms of DDIs were 38.33% pharmacodynamic, 48.33% pharmacokinetic, and 13.33% unspecified. The drug interactions were found to be positively correlated ( p < 0.01) with the 6–10 number of prescribed medicines. Conclusion According to this study, the number of medicines prescribed to cancer inpatients increased the chance of DDIs. As a result, the drug surveillance program could save a sizable number of patients from the potentially hazardous clinical effects of DDIs.

Prevalence of Potential Drug-Drug Interactions Among Hypertensive Pregnant Women Admitted to a Tertiary Care Hospital.

The aim is to determine the frequency of potential drug-drug interactions (pDDIs) and to analyze the clinically relevant drug interactions among hypertensive pregnant women. This was an observational, cross-sectional study conducted at a tertiary care hospital. The prescriptions of the hypertensive pregnant women admitted to the hospital from June 2021 to December 2021 were analyzed for potential drug-drug interactions using the database from Lexicomp ® Solutions android mobile application version 7.5.4(Wolters Kluwer, The Netherlands). A total of 127 patients were evaluated during the study period of 6 months, of which 70 (55.12%) had pDDIs. The total number of pDDIs was 85, of which 70 (82.35 %) were clinically relevant interactions with the majority of them having moderate severity (81.17%) followed by minor severity (17.65%) and major severity (1.18%). The most frequently interacting pDDIs were between Labetalol and Lornoxicam (42.35%), followed by Labetalol and Diclofenac (22.35%). This study highlights the high prevalence of potential drug interactions among hypertensive pregnant women and the need for rational drug use and strict vigilance in their monitoring.

When Context Matters for Credible Measurement of Drug-Drug Interactions Based on Real-World Data.

The frequency of potential drug-drug interactions (DDI) in published studies on real world data considerably varies due to the methodological framework. Contextualization of DDI has a proven effect in limiting false positives. In this paper, we experimented with the application of various DDIs contexts elements to see their impact on the frequency of potential DDIs measured on the same set of prescription data collected in EDSaN, the clinical data warehouse of Rouen University Hospital. Depending on the context applied, the frequency of daily prescriptions with potential DDI ranged from 0.89% to 3.90%. Substance-level analysis accounted for 48% of false positives because it did not account for some drug-related attributes. Consideration of the patient's context could eliminate up to an additional 29% of false positives.

Risk factors for potential drug–drug interactions in patients with myasthenia gravis

ABSTRACT Objectives: Our aim was to determine risk factors for and frequency of potential drug-drug interactions (pDDIs) among hospitalized patients with myasthenia gravis (MG). Methods: This was a retrospective cross-sectional study of the-first time hospitalized MG patients or patients hospitalized because of the exacerbation of MG at the Neurology Clinic of the Clinical Center of Serbia, Belgrade. Medical records and discharge summaries of hospitalized MG patients over a 10-year period were reviewed. The pDDIs were identified by means of Micromedex, and multivariate regression methods were used to reveal potential predictors of number of pDDIs per patient. Results: The study included 687 patients with MG. In total, 2041 pDDIs were detected in 608 (88.5%) patients. Among the discovered pDDIs, 329 different pDDIs were observed. The most frequent pDDIs were pyridostigmine-prednisone (487patients/70.9%) and aspirin-prednisone (90 patients/13.1%) classified as moderate, and enalapril-potassium chloride (71patients/10.3%) classified as major pDDI. Five drugs (aspirin, insulin, prednisone, cyclosporine, metformin) were responsible for 22.6% of different pDDIs. Dyspnea, generalized form of MG, diabetes mellitus, hypertension, total number of drugs-used, use of antiplatelets were identified as the relevant risk factors for total number of pDDIs (R2 = 0.626,F = 73.797, p < 0.001), while age of patients and history of cancer were inversely correlated with such an outcome. Conclusion: The frequency of the pDDIs in hospitalized MG patients is high, and adversely influenced by dyspnea, generalized MG, diabetes mellitus, hypertension, total number of drugs-used and use of antiplatelets.

Polypharmacy and Potential Drug-Drug Interactions in Home-Dwelling Older People - A Cross-Sectional Study.

BackgroundRisks associated with polypharmacy and drug–drug interactions represent a challenge in drug treatment, especially in older adults. The aim of the present study was to assess the use of prescription and non-prescription drugs and the frequency of potential drug–drug interactions in home-dwelling older individuals.MethodsA cross-sectional study design was applied. Data were collected during preventive home visits among individuals aged ≥75 in three separate communities of Western Norway. A questionnaire, which was filled out by the individual, their next-of-kin, and the nurse performing the home visit was used for the collection of demographic and clinical data (age, sex, medication use, diagnoses, need of assistance with drug administration). Potential drug–drug interactions were identified electronically by IBM Micromedex Drug Interaction Checking. Point prevalence of potential drug–drug interactions and polypharmacy (≥5 drugs) were calculated. Binary logistic regression analyses were performed to assess factors potentially associated with polypharmacy or potential drug–drug interactions.ResultsAmong the 233 individuals (mean age 78±3 years, 46% male) included in the study, 43% used ≥5 drugs, 3.4% ≥10 drugs, while 4.3% used no drugs. In 54% of the 197 individuals using two or more drugs, at least one potential drug–drug interaction was detected. Low-dose aspirin and simvastatin were most frequently involved in potential drug–drug interactions. In total, 25% of the individuals reported current use of drugs sold over the counter of which more than 95% were analgesic drugs. Potential drug–drug interactions involving ibuprofen were identified in nine of 11 (82%) individuals using over-the-counter ibuprofen.ConclusionThe study revealed a high prevalence of polypharmacy and potential drug–drug interactions with both prescription and non-prescription drugs in older home-dwelling individuals. Close monitoring of the patients at risk of drug–drug interactions, and increased awareness of the potential of over-the-counter drugs to cause drug–drug interactions, is needed.

Patients Living with HIV and Coronary Disease: Are we Using Appropriate Anti platelets as Part of Dual Antiplatelet Therapy?

Background: People living with HIV (PLHIV) have a higher incidence of cardiovascular disease and complications after intervention, including in-stent thrombosis. The frequency of potential drug-drug interactions in the setting of acute coronary syndrome (ACS) with antiretroviral therapy (ART) and dual-antiplatelet therapy (DAPT) regimens remains unclear. We sought to determine the frequency of potential drug-drug interactions in a cohort of people living with HIV who were investigated for coronary disease and initiated on DAPT as per Australian ACS Guidelines. Methods: A retrospective audit was performed in a single tertiary hospital in PLHIV presenting with symptomatic coronary artery disease (CAD) receiving DAPT. Patients were grouped based on exposure to a protease inhibitor or efavirenz and etravirine, given that these were found to have the greatest potential interactions with DAPT. Results: Fifty-three patients received DAPT, of which 31 (58%) had a potential drug-drug interaction. Clopidogrel was the most frequent P2Y12 inhibitor prescribed, accounting for 47 (87%) of the interactions. Twenty-six patients were on a protease inhibitor, of which 21 (81%) had a potential drug-drug interaction. There were 11 instances of efavirenz and 3 of etravirine use, of which all resulted in potential drug-drug interactions (100%, respectively). Conclusion: Potential drug-drug interactions were very common in PLHIV needing DAPT. The widespread use of clopidogrel in DAPT regimens resulted in a high rate of drug-drug interactions. An awareness of interactions and guidelines around P2Y12 inhibitor selection may help reduce the rate of in-stent thrombosis for PLHIV and improve clinical outcomes.

Potential Cytochrome P450 Drug-Drug Interaction Among Adult and Adolescent Patients Undergoing Tonsillectomy.

ObjectiveTo assess the frequency of potential drug-drug interactions affecting cytochrome P450 (CYP)–mediated metabolism of opioids among adult and adolescent patients who underwent adenotonsillectomy.Study DesignRetrospective chart review.SettingTertiary care university hospital.Patients and MethodsA retrospective review was conducted of 279 patients who underwent adenotonsillectomy at the University of Rochester. The discharge medication list was reviewed for all patients, and their postoperative medications were compared with a reference list published by the Food and Drug Administration and the University of Indiana’s Department of Clinical Pharmacology (Flockhart Table) to determine whether CYP-inducing or CYP-inhibiting medication was present.ResultsOut of 279 patients, 197 different medications were taken postoperatively. Approximately 70% of patients were taking 2 medications in addition to the standard postoperative analgesics (acetaminophen, hydrocodone, oxycodone, morphine, and/or ibuprofen). The 5 most commonly prescribed medications excluding the posttonsillectomy medications were oral contraceptives, ondansetron, amoxicillin, albuterol, and methylprednisolone. Four percent of patients were taking a medication that inhibits CYP3A4; <1% were taking a medication that induces CYP3A4; and 15% were taking a medication that inhibits CYP2D6.ConclusionsNearly 20% of the patients in this cohort were taking a medication that may alter opioid metabolism through induction or inhibition of CYP3A4 or CYP2D6. Some of these interactions have the potential to be more clinically relevant than others, particularly interactions that can lead to enhanced toxicity of opioids due to accumulation of active metabolites.

Potential drug-drug interactions in patients with indication for prophylactic implantation of a cardioverter defibrillator: a cross-sectional analysis

BackgroundDue to demographic transition, multimorbidity and high numbers of medicinal products, polypharmacy rates will presumably further increase. This could lead to higher risks of potentially inappropriate medications with potential drug-drug interactions (PDDI). PDDI has already been investigated by several studies, but not for patients with indication for prophylactic implantation of a cardioverter defibrillator (ICD). Thus, the objective of this analysis was to examine the frequency of PDDI in that specific group of patients and compare patients with or without PDDI regarding potential underlying factors.MethodsCross-sectional data analyses were performed using data of the prospective EU-CERT-ICD study that primarily aimed to assess ICD effectiveness in Europe. Self-reported baseline medication data of patients from Germany and Switzerland were used. Patients who reported to take at least two drugs simultaneously for at least 80 days were defined as population at risk. By means of a publicly available interaction checker, we analyzed the medication data regarding occurrence and characteristics of PDDI categorized as minor, moderate, and major PDDI. The analyses were done using descriptive methods and chi square testing.ResultsThe total population (n = 524) and the population at risk (n = 383) were rather similar with an average age of 64 years and about 80% male. PDDIs were found for 296 patients (in 57% of total population vs. 77% of population at risk). The moderate PDDI category was most frequently with 268 affected patients. Comparing patients with and without any PDDI, the proportion of patients with place of residence in Germany varied distinctly (93% vs. 78%). The frequency of any PDDI for the total population was twice as high in Germany as in Switzerland (p value < 0.001).ConclusionsPDDIs were frequently observed in this selected patient population and differed markedly between German and Swiss patients. The results should lead to higher awareness of polypharmacy and PDDIs. Adequate cooperation between health care providers should be promoted and new technologies such as drug interaction information systems or digital patient files used.Trial registrationThe EU-CERT-ICD study is registered at www.clinicaltrials.gov (NCT02064192).

Potential drug-drug interactions in acute ischemic stroke patients at the Neurological Intensive Care Unit

BackgroundClinically relevant potential drug-drug interactions are considered preventable adverse drug reactions.ObjectiveThe aim of this study was to ascertain the frequency of potential drug-drug interactions in acute ischemic stroke patients and to explore factors associated with occurrence of potentially contraindicated drug-drug interactions.MethodsThis observational retrospective cohort and nested case-control study was carried out among patients treated for acute ischemic stroke at the Neurological Intensive Care Unit in the Clinical Centre Kragujevac, Serbia. The potentially drug-drug interactions for each day of hospitalization were identifi ed using Micromedex® soft ware. Based on the existence or absence of potentially contraindicated drug-drug interactions, the participants were divided into a group of cases (n=111) and the control group (n=444).ResultsA total of 696 patients were analysed. All patients had a minimum of one potential drug-drug interaction during hospitalization. The most common drugs involved in potential drug-drug interactions were aspirin (8.02%), diclofenac (7.49%) and warfarin (7.14%). The number of medications prescribed for simultaneous use during hospitalisation and the use of antipsychotics in therapy signifi cantly increased the likelihood of potentially contraindicated drug-drug interactions aft er adjustment by means of logistic regression for 1.2 and 3 times, respectively.ConclusionsThis study suggests that patients with acute ischemic stroke are frequently exposed to potential drug-drug interactions. It is essential to identify potentially drug-drug interactions in these patients as early as possible in order to prevent adverse drug reactions and ensure safe recovery. Besides, full attention should be paid when adding each new medication in therapy, particularly when a neurologist decides to prescribe antipsychotics, such as risperidone.

Factors associated with drug interactions in elderly hospitalized in high complexity hospital.

This study aims to determine the frequency of potential drug-drug interactions (PDI) in hospitalized elderly and associated factors. This is a cross-sectional study in a teaching hospital. The dependent variable was the occurrence of potential drug interactions identified using DrugReax software. Patients with adverse drug reactions (ADR) related to clinical manifestations of PDIs were also identified. Multivariate logistic regressions was performed to analyze the association between the occurrence of PDIs and independent variables. In total, 237 older adults were included in the study. The prevalence of PDIs and interaction-related ADRs was 87.8% and 6.8%, respectively. The multivariate analysis showed a positive association between the detection of PDIs (OR 8.6; 95% CI, 2.5-30.0), and hospitalization due to a diagnosed circulatory system disease and number of medications > 14 (OR 9.8; 95% CI, 2.8-34.3%). The study showed a high prevalence of PDIs in the drug treatment of the elderly, but a lower prevalence of ADRs, as well as a positive association between PDIs and hospitalization due to a diagnosed circulatory system disease and number of medications > 14. The identification of factors associated with PDIs guides prevention measures for people that are more exposed to adverse events.

A retrospective study on potential drug interactions: A single center experience

Abstract Background In this study, it is aimed to explain the type and frequency of potential drug-drug interactions (pDDI) in patients a Medical oncology service. Methods This study retrospective descriptive design. pDDIs were identified using the checker programme (Medscape®). Interactions were classified according to their clinical relevance as minor, moderate and major as appropriate. Results The prevalence of pDDIs was 71.3% and median age was 61 years-old (interquartile range 54–68) and female to male ratio was 116/211. The median number of drugs per patient was 8 (interquartile range 5–10). A total of 1102 pDDIs of 327 hospitalized cancer patients were identified. Of those, 16.7% were major and 61.8% moderate, respectively. Concomitant use of opioids was the most common interaction in our study. Conclusions Drug interactions were common in hospitalized cancer patients. In order to prevent potential hazardous effect of pDDI, awareness of the physicians should be increased about this issue.

Detection of potential drug-drug interactions in prescriptions dispensed in hospital pharmacy

This prospective observational study examined the severity, type and frequency of potential drug-drug interactions (PDDIs) in prescriptions dispensed in the hospital pharmacies of M.S. Ramaiah Memorial Hospital and M.S. Ramaiah Hospital, Bangalore, Karnataka. A total of 500 prescriptions were collected over a period of 5 months. PDDIs were identified and analysed using Micromedex database. The frequency of PDDIs was 71.8%, with at least one interacting combination with major (14.20%), moderate (72.70%) and minor (13.09%) interactions. Out of the total PDDIs identified, 60% were pharmacodynamic interactions, 38% were pharmacokinetic interactions and 2% had interaction of unknown mechanism. The largest number of active drugs prescribed with major PDDIs were related to the cardiovascular system (32.63%), central nervous system (22.28%), gastrointestinal tract and drug metabolism (13.37%).The results of the present study showed a high frequency of PDDIs in prescriptions received at hospital pharmacies.

Pharmacoepidemiological study of drug-drug interactions in onco-hematological pediatric patients.

Onco-hematological patients are particularly susceptible to drug-drug interactions (DDIs) because they often undergo multiple combined treatments. Some studies have analyzed the frequency of DDIs in adult patients with cancer; however, the prevalence of DDIs in children, and especially among pediatric cancer patients, remains unknown. To determine the prevalence of DDIs in treatment sheets comparing two commonly used drug interaction databases, to describe the most common clinically relevant DDIs (CR-DDIs) and to investigate the risk factors associated with them. An onco-hematological pediatric unit from a tertiary hospital in Spain. A prospective, observational and descriptive study was carried out from November 2012 to February 2013. Twice a week, every patient's treatment sheet was collected. Each medication list was screened through two databases: Thomson Micromedex™ and Drug Interaction Facts™. All identified DDIs were graded by their level of severity. Summary statistics were used to describe patient and disease characteristics, most often prescribed drugs, and frequency, types and classification of CR-DDIs. Multivariate analysis was used to identify risk factors associated with CRDDIs. Prevalence of CR-DDIs was measured as percentage. A total of 506 potential DDIs were detected in 150 treatment sheets. The prevalence of CR-DDIs by Micromedex database and Drug Interaction Facts database were 44.7 and 51.3% respectively. Amikacin, azole antifungals, antiemetics and cyclosporine were the most frequent drugs involved in CR-DDIs. In multivariate analysis, the main risk factor associated with increased odds for CR-DDIs was a higher number of drugs. The frequency of potential DDIs was related to a higher number of drugs, being immunosuppressant and azole antifungal agents the most commonly involved drugs. The lack of agreement between different databases enhances the complexity to detect drug interactions in clinical practice.

Cost comparison of drug–drug and drug–condition interactions in patients with painful diabetic peripheral neuropathy treated with pregabalin versus duloxetine

The frequency and financial impact of potential drug-drug interactions (DDIs) and drug-condition interactions (DCIs) in patients with painful diabetic peripheral neuropathy (DPN) treated with either pregabalin or duloxetine were compared. This retrospective cohort study was conducted using a large U.S. administrative claims database. Patients selected for study inclusion had a diagnosis of DPN and were newly initiated on either pregabalin or duloxetine between July 1, 2008, and October 1, 2010. Data on potential DDIs and DCIs were collected. Health care costs were measured as the sum of gross covered payments for all medical and prescription claims incurred during the six months after the index date. The study sample comprised 2499 pregabalin users and 1354 duloxetine users. Among pregabalin users, 48 (1.8%) had at least one potential pregabalin DCI; none had potential pregabalin DDIs. Among duloxetine users, 966 (71%) had at least one potential duloxetine DDI or DCI. The frequencies of potential DDIs and DCIs differed significantly between pregabalin and duloxetine users (p < 0.001). Potential duloxetine DDIs and DCIs were associated with a significant increase in mean health care costs in duloxetine users (p = 0.002). Potential pregabalin DDIs and DCIs were not associated with additional health care costs in pregabalin users. Among patients with painful DPN treated with either pregabalin or duloxetine, the frequency of potential duloxetine DDIs and DCIs was substantially higher than that of pregabalin. Potential DDIs and DCIs were associated with significantly increased health care costs in duloxetine users.

PHC-002 Analysis of the Incidence of Potential Drug Interactions in Hospitalised Patients

BackgroundPrescriptions with more than one drug increase the risk of drug-drug interactions, treatment failure, large pharmacological effects and adverse events.Purpose To estimate the frequency of potential drug-drug interactions in prescriptions...

Analysis of the incidence of potential drug interactions in cardiology and internal hospitalised patients

BackgroundPrescriptions with more than one drug increase the risk of drug-drug interactions, treatment failure, large pharmacological effect and adverse events.PurposeThe objectives of this study were to estimate the frequency of...

Potential drug–drug interactions in prescriptions dispensed in community pharmacies in Greece

To evaluate the nature, type and prevalence of potential drug-drug interactions (DDIs) in prescriptions dispensed in community pharmacies in Thessaloniki, Greece. Secondary objectives included the classification of DDIs as per pharmacotherapeutic class of the medications and the investigation of the relationship between medical specialties and the frequency of potential DDIs, as well as the relationship between DDIs and prescription size. Setting DDIs are a common cause of adverse drug reactions (ADRs) among patients using multiple drug therapy. In Greece a reliable computerized surveillance system for monitoring potential DDIs is not yet fully established. As a result, the prevalence of such DDIs in prescriptions dispensed by community pharmacies in Greece is unknown. We conducted a prospective, descriptive study. Over a 3-month period (November 2007-January 2008), a total of 1,553 handwritten prescriptions were collected from three community pharmacies in Thessaloniki, Greece. The prescriptions were processed using the Drug Interactions Checker within the www.drugs.com database. The identified potential DDIs were categorized into two classes, major and moderate, according to their level of clinical significance. Overall 213 prescriptions had one or more potential DDIs and a total of 287 major and moderate DDIs were identified. Potential DDIs were identified in 18.5% of all prescriptions. Major DDIs were identified in 1.9% of all prescriptions and represented 10.5% of all DDIs detected, whereas moderate DDIs were identified in 16.6% of all prescriptions and represented 89.5% of all DDIs detected. The rate of DDIs increased with prescription size. The most common drug involved in major DDIs was amiodarone which interacts with potassium-wasting diuretics, digoxin, simvastatin and acenocoumarol. Our results indicate that patients in Greece are at risk of ADRs caused by medications due to potential DDIs. An appropriate surveillance system for monitoring such interactions should be implemented and physicians should be more aware of potentially harmful DDIs. Pharmacists can contribute to the detection and prevention of drug-related injuries, especially of clinically meaningful DDIs that pose a potential risk to patient safety.

Drug interactions and adverse events associated with antimycotic drugs used for invasive aspergillosis in hematopoietic SCT

The aim of this study was to assess the frequency of potential drug-drug interactions (pDDIs) and adverse drug events (ADEs) associated with antimycotics in hospitalized patients with hematopoietic SCT (HSCT). Of the 120 HSCT recipients evaluated, 36 received antimycotics. A total of 124 ADEs were recorded in 32 of the 36 patients treated, with 54 ADEs being possibly and 9 probably related to antimycotics. Of the treatments with amphotericin B, 93% were associated with one or more possible and 36% with probable ADEs. The corresponding figures for lipid-based amphotericin B were 100% and 7%, for voriconazole 68% and 11% and for caspofungin 70% and 0%. A total of 57 potentially severe DDIs associated with antimycotics were detected in 31 of the 36 patients. Of these, 14 DDIs were a possible cause of an ADE and 5 (4 times a combination of voriconazole with CYA and once a combination of CYA with conventional amphotericin B) were probably related. Although the prevalence of pDDIs and ADEs is high in HSCT patients, ADEs related with a high probability to treatment with antimycotics are rare. Regarding the high prevalence of pDDIs, our findings underscore the importance of close monitoring of laboratory and clinical parameters, as well as dose adjustment for critical drugs, in patients with HSCT.

Drug-Drug Interactions Associated with Length of Stay and Cost of Hospitalization

To evaluate the prevalence of drug-drug interactions (DDI) in prescriptions of hospitalized patients and to identify risk factors associated. A retrospective cross-sectional analysis of prescription data and medical records from a public hospital in Brazil was conducted to identify potential DDI. An inappropriate drug combination was identified and classified with a standard drug interaction source. The main diagnoses were classified with Charlson Comorbidity Index (CCI). Sex, age, polypharmacy and length of stay, among other variables, were correlated with the frequency of potential DDI. The study included 589 patients and 3,585 prescriptions. Thirty-seven percent of the patients were exposed to at least one potential interaction during their stay in the hospital. The most frequent interacting pair was Digoxin+Furosemide (11%). In univariate analysis, several variables were associated with DDI, including sex, age, number of prescribed drugs, length and cost of hospitalization and CCI. Multivariate analysis showed that the adjusted odds of being prescribed a potential DDI among patients in polypharmacy was almost five-fold that of patients taking less than five drugs. Further, length of stay, CCI and cost of hospitalization were independently associated with DDI. Analysis of prescription data found that a substantial number of potential DDI were identified. Results of this study indicate that DDI is associated with number of prescribed drugs, increased duration of stay in the hospital and cost, which suggest that DDI are a significant clinical and economic problem. Potential damage to patients could be avoided.