Grape seeds generally do not cause bad effects when they are eaten into the stomach, they will be digested by stomach peristalsis and gastric juices, and those that cannot be digested will be turned into feces and excreted from the body.
Grape seeds are small in size, indicating that they are round, smooth and neat, and generally do not get stuck in the esophagus or stomach wall after eating, but will enter the stomach from the esophagus along with other foods, and then remain in the stomach for about 4 hours.
Part of the grape seeds may be digested under the action of gastric juices, and most of the undigested grape seeds will be pushed into the intestines by the peristaltic movement of the digestive tract, and finally form feces together with other food residues, which will be discharged out of the body along with the intestinal peristalsis.
So in general grape seeds eaten into the stomach will not cause adverse effects on the body, but if there is obvious discomfort, you should also promptly go to the hospital.