Patient knowledge about his medication: relationship between knowledge and perceptions of effectiveness and safety of the treatment

Introduction: For best results of drug the patient should have some basic knowledge about their medication. The pharmacist is ideal for checking patient knowledge gaps and completing their information. 

Material and method: In 1926 pharmacies throughout Spain, between January and June 2012, all patients requiring bisphosphonates, anti-asthmatics, benzodiazepines, statins or NSAIDs were interviewed to investigate whether they know the symptoms, dosage, method of use and treatment duration, and to correct or complete the information as necessary. If they have already used the drug they were asked about their perception of effectiveness and safety of it.

Results: Data on 199,957 dispensations were obtained. The patient does not know symptoms in 5% of cases, dosage in 6%, manner of use in 10% and treatment duration in 40%. Whenever a patient does not know about a certain aspect of the treatment, their perception of ineffectiveness is greater: indication 1.4% when known, 3.4% when does not know, dosage 1.3% - 5.5%, method of use 1.3% - 4.6%, treatment duration 1% - 2.1%. The same applies to safety. If something is unknown the patient perceives their drug as less safe. Symptoms 6.5% - 8.6%, dosage 6.3% - 13.4%, manner of use 6.2% - 13.4%, treatment duration 5.7% - 7.9%.

Conclusions: At the moment of dispensing, the patient lacks information about their treatment, and these deficiencies adversely affect the perception of the patient about the effectiveness and safety of their drugs.