Recent studies have suggested a link between antiplatelet medications and alcohol in the aetiology of acute adult epistaxis. The possibility that adult epistaxis may be associated with alcohol induced platelet dysfunction has not previously been investigated. This study evaluated primary haemostasis in 50 adult patients with idiopathic epistaxis. A detailed alcohol history was recorded and the Simplate bleeding time device was used to test haemostatic function. Forty-six per cent of patients were found to have an abnormality of primary haemostasis. Prolongation of the bleeding time was significantly associated with a history of alcohol use. The effect of alcohol on the bleeding time duration was significant (P < 0.001) even at low levels of intake of between 1 and 10 units per week. Although prevalent in the study group (42%) the use of non-steroidal anti-inflammatory drugs did not confer a significant additional risk of increased bleeding time. These findings support the importance of alcohol induced haemostatic abnormalities in the aetiology of adult epistaxis.