Rash
Some patients may experience a
rash that waxes and wanes if they immediately stop taking whey
powder. This occurs because the body's immune system inappropriately reacts to the proteins in whey powder, resulting in an immune reaction. A rash is most likely to occur when whey powder is suddenly discontinued, states Drugs.com. Therefore, you can avoid a rash by slowly reducing your intake of whey powder if you decide you do not want to take the supplement.