The Global Initiative for Asthma (GINA) has presented a shift in pharmacological asthma treatment. The objective of this study was to explore factors influencing a successful switch to a new asthma treatment approach with a focus on asthma patients’ attitudes toward treatment change and supportive initiatives. This study was performed as a case study involving a quantitative questionnaire and a qualitative semi-structured interview. A total of 284 responses were collected from the questionnaire, and 141 responses were included. The results showed that asthma patients thought that effectiveness of the new treatment approach, doctor recommendation, and knowledge of the new treatment approach were the most important factors influencing treatment change considerations. Nine interviews were conducted where the main themes were barriers to a shift in asthma treatment, such as effects and side effects of the new treatment, the role of the general practitioner (GP) and conflicts in agreeing on a treatment plan; as well as facilitators to a shift in asthma treatment, such as trust in the GP and easier inhaler use. We found several supportive initiatives, such as consultation with the GP, handing out information leaflets and a consultation at the pharmacy. In conclusion, this study uniquely identified factors that may influence successful treatment shifts in asthma patients that may be instrumental in understanding similar situations in other pharmacological settings.