Can grapes give you constipation?

No, usually not: Grapes are fruit, with juice and sugar, so they don't tend to cause constipation. Eating too much fruit might cause the loose stools. The main problem in constipation is that the time it takes for food one ate to go through the intestine and out the anus is too long of a time. One must make "intestinal transit" time more rapid. Water plus fiber helps, but sometimes laxatives are needed.