Creatine levels above the normal range of 0.6 to 1.2 milligrams per deciliter for men and 0.5 to 1.1 milligrams per deciliter for women would be considered high, according to MedicineNet.com. At 10.0 milligrams per deciliter it indicates severe kidney malfunction.
Creatine levels check kidney function. Muscular adults can have more than the normal and still be fine, while elderly individuals may have less and still be fine, according to MedicineNet.com. The normal range for those with only a single kidney is 1.8 to 1.9 milligrams per deciliter. Diabetes and high blood pressure can be one cause of raised creatine levels as well as some medications.