Medication non-adherence in asthma and COPD patients have been established to be very high, and along-side poor knowledge of proper use of inhaler devices, results in suboptimal disease control among these patients. Studies evaluating the impact of a comprehensive intervention on medication adherence and inhaler usage on disease control are scare in developing countries. This study was a prospective single-blind quasi-randomized-controlled study among asthma and COPD patients attending the chest out-patient clinic of the University College Hospital, Ibadan. The baseline questionnaire was administered to consenting patients to explore demographic and specific clinical characteristics, knowledge of the disease, current medications, medication adherence, knowledge of use of metered dose (MDIs) and diskus inhalers, and asthma/COPD control status using the asthma control test (ACT) and COPD assessment test (CAT) scales. Subsequently, patients were assigned into intervention or control groups using odd or even number assignation. Patients in the intervention group were followed up for two months via face to face interviews, short message services, and phone calls at one-weekly intervals, so as to provide education and counseling to resolve the identified gaps during the baseline interaction. Descriptive statistics were used to summarize the data, while chi-square, t-test, Fishers exact test and Wilcoxon-signed ranked tests were used as appropriate to test for associations at p \< 0.05.