According to the National Library of Medicine, it is safe for adults to drink Pedialyte. It is effective in reducing dehydration. WebMD explains that Pedialyte replaces fluids and minerals that have been lost because of diarrhea or vomiting.
WebMD indicates that Pedialyte is available in liquid form, which is consumed as packaged. It also comes as a powder that is mixed with water. Side effects include mild nausea or vomiting. However, if the product is consumed slowly by spoon, patients do not usually experience these reactions. Rare but more serious side effects include dizziness, weakness, ankle or foot swelling, mood changes and seizures. Medical attention is needed if any of these occur.