After taking Zofran, you can drink water immediately. However, it is generally recommended to wait 20-30 minutes to allow the medication to start working, which can help better tolerate anything in the stomach if nauseated and avoid immediate regurgitation of the water. When taking the regular Zofran tablet, it is advised to swallow it with a full glass of water. For orally disintegrating tablets, water is not necessary during intake, but drinking water afterward is fine.