Smoking induces “nonresponse” under ASA and Ticlopidine treatment

P217 Smoking is assumed to be a risk factor in stroke-patients. Ticlopidine or ASA should prevent from stroke by inhibition of platelet function. Platelet function i.e. platelet reactivity (PR) (Grotemeyer, Thrombosis research 63;587) was determined before and after smoking without drugs, 2 hours after intake of ASA or ticlopidine and 5 days after loading with 2 x 250 mg ticlopidine/day . At each experiment 3 cigarettes (Marlboro ®) were smoked within 30 min. Blood was collected immediately before smoking and 30 min later. A washout period of 14 days was between each drug-experiment. Included were 23 healthy male smokers (age 25,2 ± 3,3 yr.) PR (before smoking) was 1.15 ± 0,15, after smoking 1,42 ± 0,18. Average difference (AD)(PR after - PR before smoking) was 0,28 ± 0,13. Pathological PR-values (>1.25) were seen in 95% of the smokers after the experiment. (Wilcoxon p