Medication adherence is defined by the World Health Organization (WHO) as "the degree to which the person‟s behavior corresponds with the agreed recommendations from a health care provider, Adherence to therapies is a primary determinant of treatment success. The aim of the current study to compute the level of medication adherence in hospitalized and non hospitalized patients in order to compare between them and demonstrate the effect of non adherence on hospitalization rate. Sixty patients were participating in the current study (30 hospitalized, 30 non hospitalized) with age ≥ 18 years old, using morisky questionnaire and general questionnaire to collect information that relate to the patient lifestyle, diet, age, sex etc. It was found that 60% of hospitalized patients involved in the study had low adherents, 26.6% medium and only 13.3% were high adherents compared to non hospitalized with 33.3% being high adherents, 33.3% low and medium adherents, and the direct relationship between decreased adherence and increased hospitalization rates, also noticed the effects of age, complexity of treatment, patient provider interactions and unwanted side effects of medications on the rates of adherence. The study found that low adherence was higher in hospitalized patients; the rate of high adherence was increased in non hospitalized patients. Adherence to prescriptions is linked to age, patients' beliefs, education about their health, their trust in health care workers.