The time taken by Eupace-L Tablet ER to start working varies from person to person. Usually, Eupace-L Tablet ER starts working within 15 minutes. However, in some patients, it may take up to 2 hours to start working. It starts acting slowly and the maximum or full effect is usually experienced within a span of 1 week. In case you do not feel any difference while taking Eupace-L Tablet ER, do not panic. The medicine exerts its beneficial effects when taken for a long time.