i don't think that the penny will cause in corrosive response but it is concerning that it is still in the stomach and has not travelled to the intestinal tract after 10 days. at some point in the near future if the penny still remains in the stomach it may need to be removed under sedation using a gastroscope.
can a penny made after 1982 be harmfull to stomach linning. three year old swallowed penny many x-rays later and 10 days it is still in the same place in the stomach having moved up only a little 3 days in. one medical person says may be corrosive and another says no. i just wonder is it possible.