Grape is LIKELY SAFE when consumed in amounts commonly found in foods.
Grape is POSSIBLY SAFE when taken by mouth in medicinal amounts. Grape seed extracts have been used safely in studies for up to 14 weeks. Eating large quantities of grapes, dried grapes, raisins, or sultanas might cause diarrhea. Some people have allergic reactions to grapes and grape products. Some other potential side effects include stomach upset, indigestion, nausea, vomiting, cough, dry mouth, sore throat, infections, headache, and muscular problems.
Special Precautions & Warnings:
Pregnancy and breast-feeding: Not enough is known about the use of grape in medicinal amounts (supplements or amounts that are higher than normal food amounts) during pregnancy and breast-feeding. Stay on the safe side and avoid use.
Bleeding conditions: Grape might slow blood clotting. Taking grape might increase the chances of bruising and bleeding in people with bleeding conditions. However, there are no reports of this occurring in humans.
Surgery: Grape might slow blood clotting. It might cause extra bleeding during and after surgery. Stop using medicinal amounts of grape at least 2 weeks before a scheduled surgery.