Indication : It is used for conditions that affect the heart such as heart failure, chest pain, and high blood pressure. It is also used for preventing migraine headache, Parkinson’s disease, and many other conditions. Side effects : It can cause some mild side effects including stomach upset, loss of appetite, nausea, vomiting, and diarrhea. When not to use: Hypersensitivity to the drug. Pregnancy : There appears to be no risk when taking this drug during pregnancy. Precaution : People with chronic diseases such as heart failure, kidney or liver problems, or diabetes should be wary of using this supplement. Precaution : Coenzyme Q10 might interfere with blood pressure control during and after surgery. Stop using coenzyme Q10 at least two weeks before a scheduled surgery. Precaution : It might lower blood pressure. It can increase the effects of medications used to lower blood pressure. Discuss your use of coenzyme Q10 with your healthcare provider if you have blood pressure problems.