Zocor and mum

I am writing regarding my mum. She is 73 years old. She attends hospital for a blood disorder and high blood pressure. She already takes Praxilene for blood disorder and Co-Amilozide for blood pressure. When attending hospital last year, she was told after further tests for cholesterol that the result was not high, however was prescribed Simvastatin 40mg 1xday. She has since developed muscle symptoms - so much so that often she is in pain and can barely walk. Also has swelling in legs. Has anyone else developed these symptoms?