Aim: This study examined modifications in secondary preventive medication between the time of hospital discharge (HD) and during a 6-month follow-up treatment of outpatients with acute coronary syndromes (ACS) and stroke. Subjects and methods: During a 6-month period, a health diary was completed on a weekly basis by 98 patients who were initially hospitalised with ACS and 29 patients with strokes in the Cologne area (Germany). Changes in medication between the time of HD and follow-up treatment (weeks 2, 12, and 24) were recorded. Results: On average, patients with ACS took six medications, whereas patients with stroke took five medications per day. ACS patients received beta-blockers (96%), lipid-lowering agents (80%), and angiotensin-converting enzyme (ACE) inhibitors (64%) at HD, and no changes in medication were made during follow-up treatment. However, there was a significant decrease in prescriptions of clopidogrel among ACS patients within 6 months, and about 13% of ACS patients did not receive an antiplatelet agent at any time. Stroke patients received beta-blockers (50%), lipid-lowering agents (67%), and antiplatelet agents, such as acetylsalicylic acid (57%) or clopidogrel (27%), at the time of HD, and no significant changes in medication were instituted during follow-up treatment. Conclusion: Treatment of ACS patients with the combination of acetylsalicylic acid and clopidogrel was insufficient, although it has been shown that this combination is highly effective in secondary prevention of ACS. Besides medical reasons, the cost-containment restrictions (“medication budget”) for German physicians might explain the observed failure of guideline-oriented medication. Furthermore, no changes in medications occurred regarding blood-pressure- and lipid-lowering agents