Studies on combination dosing (III). Aspirin and ethenzamide.

In our studies with drug combinations, we search for mixtures which would enhance the effectiveness of the related active substances. Ethenzamide was found to possess a specific suppressive effect on the gastric damage induced by aspirin. Such effect could not be demonstrated in analgesic agents such as salicylamide, bucetin, acetaminophen and phenacetin. The combination of aspirin with ethenzamide had a potentiating effect on analgesic activity and reduced motor incoordination and loss of righting reflex. We calculated the safety margins of various ratios of combinations and concluded that the best was aspirin and ethenzamide at a ratio of 2:3.