The growing number of medicinal products and innovations has led to great complexity in the pharmaceutical market. The variety of possible drug interactions and side effects can only be overviewed with difficulty. Therefore, it is necessary that services for physicians be offered in order to provide critically evaluated and independent drug information for pharmacotherapy. In recent decades, a series of hospital based drug information centres have been established. Their quality and usefulness for patients have been positively evaluated by the users. Many patients are also insufficiently informed on their own drug therapy. This deficit is based on a general lack in communication between the patient and physician. Patient-orientated drug information services can help strengthen patients in their drug therapy and self management of symptoms, and to improve compliance. Such services have also been positively evaluated by patients.