Yes, it can. Testo Lab Pro contains a wide range of ingredients and some of them are associated with side effects. For instance, ashwagandha may cause drowsiness, upset stomach, and nausea. If you are experiencing any side effects, discontinue taking the supplement and consult your doctor.Yes, it can. Testo Lab Pro contains a wide range of ingredients and some of them are associated with side effects. For instance, ashwagandha may cause drowsiness, upset stomach, and nausea. If you are experiencing any side effects, discontinue taking the supplement and consult your doctor.