Creatinine is a metabolic product produced by creatine and phosphocreatine in the muscles and its daily production is constant. A small amount of creatinine is produced from meat-based foods that are obtained from the daily diet. Creatinine will be carried through the blood to the kidneys. The kidneys will filter the creatinine and remove it through the urine.
The creatinine clearance test measures the amount of creatinine that has been removed from the blood into the urine over a 24-hour period.
Causes of Increased and Decreased Creatinine in the Body
The normal level of creatinine in the blood in adults is 0.8-1.2 mg/dL. However, the value range may vary in each laboratory.
Creatinine levels will usually be higher in young adults or people who have a lot of muscle tissue, for example athletes or people who often exercise weight lifting.
However, in addition to factors such as age, activity, and body muscle mass, increased creatinine levels can also be caused by certain medical conditions or diseases, such as:
- Kidney problems, such as kidney failure, kidney stones, and kidney infections
- Dehydration
- Rhabdomyolysis
- Hypertension
- Diabetes
- Side effects of certain drugs, such as antibiotics, chemotherapy drugs, and diuretics
- Side effects of certain drugs, such as antibiotics, chemotherapy drugs, and diuretics
Conversely, creatinine levels may decrease in people with malnutrition or liver disease. A decrease in creatinine levels is also often experienced by the elderly.