HighlightsWhat are the main findings?The proportion of nonadherence to medication in asthma patients was very high (22.3%), and patients’ behavior was the main reason (44.1%).Clinical pharmacist-led intervention in enhancing medication adherence in asthma patients, increasing treatment efficacy, relieving symptom severity, and reducing the medication burden from the disease.What is the implication of the main finding?Intervention in medication adherence applied strictly following the education and counseling method would be beneficial for every healthcare practitioner to enhance the treatment outcome.Intervention in medication adherence should emphasize young patients and those with limited mobility.AbstractBackground: Medication adherence in asthmatic patients enhances the effectiveness of treatments, but some studies in low and middle-income countries still show some limitations. Our study aimed to determine if pharmacist-led interventions could increase medication adherence, improve treatment effectiveness, and relieve symptom severity in outpatients with asthma. Methods: We conducted a randomized, controlled trial on 247 asthmatic outpatients (aged ≥ 16) with a 1:1 ratio randomization at the hospitalization time and repeated after 1-month discharge. The primary outcome was to detect the difference in medication adherence between groups. Adherence was assessed by the general medication adherence scale (GMAS). Data collected by questionnaire was coded and entered into SPSS_20 for statistical analysis; Results: 247 patients (123 intervention, 124 control) were enrolled (61.1% male). After intervention, the adherence rate was higher among the intervention group than the control group (94.3% vs. 82.8%,p= 0.001). Patient behavior and knowledge were enhanced in the intervention group (p< 0.05). Asthma symptoms were relieved in the intervention group (p= 0.014). Pharmacist-led interventions on adherence rate were higher with OR: 3.550, 95% CI: 1.378–9.143,p= 0.009. Conclusions: pharmaceutical intervention could improve medication adherence, treatment efficacy, and the outcome should not be taken for granted; further research should be carried out in this regard.