OBJECTIVES: To evaluate the budget impact of guideline adherent acute coronary syndrome (ACS) therapy over 12 months from the perspective of statutory sick funds in Germany. METHODS: Most current clinical guidelines recommend clopidogrel (in addition to ASS), beta blockers, ace-inhibitors and statins for at least 12 months after ACS. We evaluated the potential 1 year budget impact of improving the medication pattern in ACS towards an optimal drug usage as defined by the guidelines. Clopidogrel effect estimates were from the CURE and CLARITY study, effect estimators for the other recommended drugs were obtained from meta-analyses. Due to uncertainty regarding the additive effects three scenarios were calculated: 1) “minimum” effect (2 out of 4 drugs add additively), 2) “mean” (3 out of 4 drug effects) and 3) “maximum” (all 4 drug effects are additively). Costs were modelled using recent drug prices and published German event costs. RESULTS: For 350'000 ACS patients (including 40% ST-elevation myocardial infarction) compared to a drug utilization pattern as in CURE 15’676 to 20’793 events (Scenario 1 to 3) could be avoided. This assumes an optimal achievable guideline adherence rate of 95% for clopidogrel and statins, 90% for ACE-inhibitors and 85% beta blockers. The corresponding additional costs for improved guideline adherent therapy are between +3.2% and -1.9% compared to baseline. Costs per event avoided are between 1’882€ and -824€. Mean costs per patient increase by 84€ to -49€ given yearly mean calculatory costs of 2’636€. Besides the uncertainty accounted for by the scenarios uni- and multivariate sensitivity analysis showed stable results. CONCLUSIONS: In clinical practice an improved adherence of physicians to post ACS medication guidelines would result in a minor increase or even decrease of budget for the German sick funds. Furthermore, a significant reduction of major cardiovascular events after ACS could be achieved.