Background Patients with Parkinson’s disease needs medicines administered frequently to manage their condition and maintain their quality of life. Poor medicine adherence may influence health negatively, and cause an unnecessary medicine wastage. It is therefore important that they are effectively supported to ensure that they adhere to their medicine regime. The aim of the study is to identify barriers to medicine adherence in patients with Parkinson’s disease or Parkinsonism and to identify interventions to improve medicine adherence. Method A postal questionnaire containing 39 statements was sent to 430 patients. The statements were used to identify patient barriers to adherence. A focus group consisting of healthcare professionals discussed interventions to improve medicine adherence. Results 229 (53,3%) patients responded to the questionnaire. The main barriers to adherence are; having enough time with doctor and pharmacist; being requested to attend to follow-up sessions; knowing where to get help if needed; having the ability to solve problems appearing when taking medicines; worry about side-effects; feeling that taking medicines is a burden and knowing enough about their medicines to decide whether to take them. Disease length did not relate to the responded barriers to non-adherence. Motivation- intention and ability to remember- to take medicines are important barriers to non-adherence. Conclusion There are several barriers to medicine adherence in the study population, indicating there is a need for interventions from healthcare professionals to improve adherence and increase the health of this patient group