Adverse drug reactions impact on patient health, effectiveness of pharmacological therapy and increased health care costs. This investigation intended to detect the most critical drug-drug interactions in hospitalized elderly patients, weighting clinical risk. We conducted a cross-sectional study between January and April 2014; all patients 70 years or older, hospitalized for >24 hr and prescribed at least one medication were included in the study. Drug-drug interactions were estimated by combining Stockley's, Hansten and Tatro drug interactions. Drug-drug interactions were weighted using a risk-analysis method based on failure modes, effects and criticality analysis. We calculated a criticality index for each drug involved in the drug-drug interactions based on the severity of the interaction mechanism, the frequency the drug was involved in drug-drug interactions and the risk of drug-drug interactions in patients with impaired renal function. The average number of drugs consumed in the hospital was 6 AE 2.69, involving 160 active ingredients. The most frequent were as follows: Furosemide, followed by Enalapril. Of drug-drug interactions, 2% were classified as contraindicated, 14% advised against and 83% advised caution during the hospital stay. Thirty-four drug-drug interactions were assessed, of which 23 were pharmacodynamic drug-drug interactions and 12 were pharmacokinetic drug-drug interactions (1 was both). The clinical risk calculated for each drug-drug interaction included heparins + non-steroidal anti-inflammatory drugs (NSAIDs) or Digoxin + Calcium Gluconate, cases which are pharmacodynamic drug-drug interactions with agonist effect and clinical risk of bleeding, one of the most common clinical risks in the hospital. An index of clinical risk for drug-drug interactions can be calculated based on severity by the interaction mechanism, the frequency that the drug is involved in drug-drug interactions and the risk of drug-drug interactions in an elderly patient with impaired renal function.Drug-related problems (DRP) are a very important public health concern that cause adverse drug reactions (ADR), which impact on patient health, effectiveness of pharmacological therapy and increased healthcare costs [1]. Drug-drug interactions have been reported to account for 5.6% to 63% of medication-related problems (MRPs), particularly in elderly patients, where the prevalence of at least one drug-drug interaction is about 46% [2]. The conditions of elderly patients, such as a decline in the functional capacity of most organs and systems, comorbidity and, in turn, polypharmacy (more than five drugs), make this population more susceptible to drug-drug interactions, resulting in a long hospital stay or death [3,4].There are many studies that report the prevalence of drugdrug interactions, while focusing on identifying the implicated drugs and the type of clinical effect on the patient [5,6]. Currently, research has focused on knowing the DDI action mechanisms, which allows assessment of their relevance and ...

Background/Aim Medication prescription is a fundamental component in the care of the elderly. Several characteristics of aging and geriatric medicine affect prescriptions for these people and make the selection of drug therapy a difficult and complex process. The objective of this study is to develop a geriatric portal for asynchronous online counseling (AGAlink) for use by physicians specializing in family medicine to reduce medication problems among older adult patients in the first level of care. Method A qualitative study was carried out in the first level of care at the Mexican Institute of Social Security (IMSS), 31 family doctors were interviewed to identify attitudes, preferences about the use of the AGAlink geriatric portal, as well as their recommendations for the implementation of this tool in their daily practice. For the analysis of the data obtained, a qualitative thematic content analysis was used. Results 90% of the physicians used the geriatric portal outside office hours without the need for the patient to be present. The perception of the physician towards the use of the AGAlink geriatric portal was favorable, provided relevant information and had several positive effects on the process of care for medical prescription. The barriers identified to accept the change in medication were not having the proposed therapeutic option, lack of any laboratory analysis, continuing to consider their experience for the prescription of the medication. Conclusions The AGAlink geriatric portal was a tool that was well received by physicians who expressed a positive attitude, considered an investment of a short time that allowed them to update and learn about strategies to reduce the prescription problems presented among the elderly population. However, the main barrier was the use of technology, especially in the doctors with more seniority in the service.