Duaa for breaking fast

Assalamu aleykum, when breaking our fast we say this duaa : The thirst is gone, and the veins are moistened and the reward is certain InshaAllah. My question is, how do we interpret this since we say it right after we break the fast so our veins don't moisten immediately for instance. So is it more of a description of the process? Any answer would help. Jazakum Allahu khairan.