Introduction: To reduce the morbidity and mortality of cardiovascular diseases, patients are emphasized on following the exact prescription order of their antihypertensive and other cardio vascular medications.

Materials and Methods: The purpose of this study was to identify factors related to medication compliance in patients with coronary heart disease. A descriptive analytical study was designed and a total of 150 patients with coronary heart disease were chosen with convenience sampling among patients in one of the cardiovascular clinics affiliated to Tehran University of Medical Sciences. The instrument included a questionnaire for the demographic data, side effects of the drugs, physical condition, level of cognition and self-reporting of the patients about medication non-compliance A questionnaire which was about attitude evaluation A data evaluation form to calculate the rate of medication compliance Biophysiologic measurments and finally, available documents. The data were collected in two consecutive steps: at the first appointment, the questionnaires were filled. At the second appointment (1 month later) medication compliance rates which was based on counting of pills, were calculated.

Results: The data were analyzed with descriptive statistics, chi-square test, Fisher’ exact test and Tchoprof coefficient. Only 28% of the patients had met the drug regimens appropriately but 56% of them had a poor record. There was a meaningful relationship between the self – reporting of the patients and counting of the pills (p value<0.005). In addition, some factors such as age, education, occupation, teaching and its sources, duration of acquiring the cardiac disease, number of hospitalization and level of cognition of patients under investigation were assessed as effective elements to use the pills properly.

Conclusion: No meaningful relationship was found between sex, marital status, parenthood status, living arrangement, health insurance situation, health personnel availability, positive family history of cardiac disease, co-existence of another disease, difficulty in providing of the drugs, side effects of the drugs, physical condition and attitude and medication compliance. In conclusion, by providing some educational programs about drug regimens, based on the level of cognition, experiences, capabilities, and also the living style of the patients, medication compliance can be improved.