The possibility of interaction occurrence among drugs prescribed in primary health care

Abstract

<p>Contemporary pharmacotherapy is based on a large number of very different therapeutic gents, and a widespread polypharmacy can lead that drugs interact among themselves i sense of augmentation or attenuation effects. Despite of thousands of published studies n drug interactions, a relatively small number is clinical important. Therefore, the importance of drug interactions primarily involves the knowledge or prediction of those situations when possible interactions have clinical important implications, as well as knowledge of measures which should be taken in that case for their avoidance or selection of safer, alternative treatment. To predict and control the possible consequences during co-administration of two or more drugs, besides knowledge on the pharmacological mechanisms involved in the occurrence of drug interactions, it is also necessary knowing the most vulnerable groups of patients as well as high-risk drugs. The aim of the study was to identify the frequency and type of potential drug-drug interactions (pDD Is) in ambulatory patients of the Health center Novi Sad, as well as to establish the predictive role of risk factors, those which are patient characteristics and those which are therapy characteristics for exposure to pDDIs. Cross sectional study was conducted. The analysis randomly included 10percents outpatients with polypharmacy (n=4467) who visited the Health center Novi Sad over I-month period (November1 -30, 2011). All drug combinations with potential for interactions were identified. Slightly more than 50percents of the patients at the Health center were exposed to pDDIs, and approximately 60 percents exposed patients had at least one clinical significant potential drug -drug interaction. Risk for exposure to pDDIs was increased by patient age and number of morbidity. Metabolic, circulatory, mental, nervous, diseases of respiratory an genitourinary system were predictors, while the gender was not risk factor for exposure o potential interactions. Complex treatment regimens, more precisely major polypharmacy, and prescriptions for the disease of .metabolism, cardiovascular, nervous and respiratory systems were therapy characteristics which represented risk factors for occurrence potential interactions. Cardiovascular, followed by drugs for nervous system and metabolism were the most commonly involved in the potential interactions. ~he prevalence pDDIs where were involved beta blockers, angiotenzin converting&nbsp; enzyme inhibitors, diuretics, digoxin, statins, antiarrhythmics and hypoglycemic drugs was increased by patient age. Contrary, the prevalence of potential interactions where were included anticonvulsant, antipsychotics and antidepressants from the&nbsp; group serotonin reuptake inhibitors was decreased by patient age. The large proportion of the identified drug-drug interaction pairs presented the part of usual therapeutic regimen. Approximately two-thirds of the exposed patients had increased risk for side effects or drug toxicity (prolonged sedation, hypotension, arrhythmias, hypoglycemia, and others), and slightly less than one-third for decreased effectiveness of drugs (attenuated effects of , antihypertensives, antidiabetics, theophylline, benzodiazepines and others). Recommendations for the management of pDDIs included the monitoring of drug co-&nbsp; administration, avoiding concurrent use of drugs that interact, different risk modifying strategy, adjust dose and contraindications for concurrent use of drugs with the potential to interact.</p>