OBJECTIVES:  Multiple sclerosis (MS) is one of the most frequent neurological diseases and is associated with elevated health care costs. This study provides further insights into these costs by differentiating between patients using different MS drugs and by analysing different cost categories. METHODS:  The database consists of German claims data from 2006 to 2010. For the MS patients  expenses of different cost categories are analysed for each type of MS medication in the year 2009. These categories cover costs for disease modifying drugs, symptomatic drug therapy, primary care and hospitalization. RESULTS: In 2009, the mean annual costs per patient amounted to roughly 15,000€ for disease modifying drugs and about 270€ for symptomatic drug therapy. Among the MS medications, Natalizumab caused the highest treatment costs (25,104€), followed by Interferon beta-1a and Interferon beta-1b with comparable costs (16,211€ and 16,519€) and Glatirameracetate (12,617€). Azathioprine caused the lowest annual treatment costs (450€). The expenditure for primary care (1,459€), hospital services (2,157€) and symptomatic drug therapy (334€) is high for patients using Natalizumab, a drug which is indicated for patients with highly active MS. Patients using Interferon beta-1a, Interferon beta-1b and Glatirameracetate have similar expenses in those cost categories (on average 872€ for primary care, 1409€ for hospital services and 212€ for symptomatic drugs). Patients using Azathioprine have increased costs for symptomatic drug therapy (316€) and hospital services (2,578€), while primary care expenditures are comparable to patients using other basic MS therapy (770€). CONCLUSIONS: The costs for specific MS medication makes up for 88% of the total annual drug costs of MS patients. The expenses for other cost categories are similar for patients treated with basic MS medication but higher for patients using escalating MS therapy. Azathioprine is associated with lower medication costs but with slightly higher expenses in the other observed cost categories.