A method for treating or preventing a thrombosis in a person in need thereof comprising disposing in or on an article an effective antithrombotic amount of a composition and providing the article to be in close proximity to the skin of the person, the composition comprising (i) alumina, (ii) at least one substance selected from the group consisting of silica and titanium oxide and (iii) at least one element or compound selected from the group consisting of platinum, a platinum compound, palladium, a palladium compound, iridium, an iridium compound, rhodium and a rhodium compound.
