What Are The Side Effects Of Lisinopril?

I have been diagnosed with Dilated Cardiomyopathy. My cardiologist has put me on Coreg. My family doctor put me on Lisinopril for a time until my cardiologist changed it to Cozaar. I was researching the medications online and decided they are double dutying the job. I have been experiencing some serious side effects of both medications. Am I being overdosed with basically the same meds?