Creatinine - blood
Creatinine is a breakdown product of creatine, which is an important part of muscle. This article discusses the laboratory test to measure the amount of creatinine in the blood.
Creatinine can also be measured with a urine test. See: Creatinine - urine
How the test is performed
A blood sample is needed. For information on how this is done, see: Venipuncture
How to prepare for the test
The health care provider may tell you to stop taking certain drugs that may affect the test. Such drugs include:
- Aminoglycosides (for example, gentamicin)
- Heavy metal chemotherapy drugs (for example, cisplatin)
- Kidney damaging drugs such as cephalosporins (for example, cephalexin)
- Nonsteroidal anti-inflammatory drugs (NSAIDs)
How the test will feel
When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.
Why the test is performed
The test is done to see how well your kidneys work. Creatinine is removed from the body entirely by the kidneys. If kidney function is abnormal, creatinine levels will increase in the blood (because less creatinine is released through your urine).
Creatinine levels also vary according to a person's size and muscle mass.
A normal result is 0.7 to 1.3 mg/dL for men and 0.6 to 1.1 mg/dL for women.
Females usually have a lower creatinine than males, because they usually have less muscle mass.
The examples above are common measurements for results of these tests. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your doctor about the meaning of your specific test results.
What abnormal results mean
Higher than normal levels may be due to:
- Acute tubular necrosis
- Diabetic nephropathy
- Eclampsia (a condition of pregnancy that includes seizures)
- Kidney failure
- Muscular dystrophy
- Preeclampsia (pregnancy-induced hypertension)
- Reduced kidney blood flow (shock, congestive heart failure)
- Urinary tract obstruction
Lower than normal levels may be due to:
- Muscular dystrophy (late stage)
- Myasthenia gravis
Additional conditions under which the test may be performed:
- Alport syndrome
- Atheroembolic kidney disease
- Chronic kidney disease
- Cushing syndrome
- Dementia due to metabolic causes
- Digitalis toxicity
- Ectopic Cushing syndrome
- Generalized tonic-clonic seizure
- Goodpasture syndrome
- Hemolytic-uremic syndrome (HUS)
- Hepatorenal syndrome
- Interstitial nephritis
- Lupus nephritis
- Malignant hypertension (arteriolar nephrosclerosis)
- Medullary cystic kidney disease
- Membranoproliferative GN I and GN II
- Type 2 diabetes
- Polymyositis (adult)
- Prerenal azotemia
- Thrombotic thrombocytopenic purpura
- Wilms' tumor
What the risks are
There is very little risk involved with having your blood taken. Veins and arteries vary in size from one patient to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight but may include:
- Excessive bleeding
- Fainting or feeling light-headed
- Hematoma (blood accumulating under the skin)
- Infection (a slight risk any time the skin is broken)
Landry DW, Bazari H. Approach to the patient with renal disease. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 116.
The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed medical professional should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. ©1997-2013 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.
Sign Up for Free Newsletters
Ask Your Doctor the RIGHT Questions!
the most from your doctor visit.
Emailed right to you!
The Ask Your Doctor email series
may contain sponsored content.
18+, US residents only please.
Explore Original Articles About...
Get the MOST from QualityHealth
- Top Searches
- 1. Arthritis Management: Nature Heals
- 2. 5 Digestive To-Dos
- 3. Men: Should You Shave It or Leave It?
- 4. Today's Top Fitness Trends
- 5. Sugar and Osteoarthritis : The Link
- 6. Can't Afford Your Hospital Bills?
- 7. Stay Energized All Day Long
- 8. Phobias: Who Has Them and Why?
- 9. What If Your EpiPen Fails?
- 10. 5 Costly Medical Billing Mistakes
- 1. Ice Falls Can Cause Serious Injuries
- 2. Can Inactivity Act Like a Disease?
- 3. Kale Snack Recipe for Diabetics
- 4. How Running Affects Arthritis
- 5. Sugar and Your Immunity System
- 6. Do Weight Loss Supplements Work?
- 7. 5 Super Foods for Spring
- 8. The Hazards of Reusable Bags
- 9. How to Avoid Ingrown Hairs
- 10. Health Tip: Constantly Change Shoes
- 1. 4 Common Treatments for Epilepsy
- 2. What Does a Urogynecologist Do?
- 3. GERD Without Heartburn? It's Possible
- 4. Graston Technique: Can It Work on You?
- 5. Music Therapy Can Help Autism
- 6. 8 Ways to Fight MS-Related Fatigue
- 7. Can You Still Bleed After Menopause?
- 8. Be Your Own Health Care Advocate
- 9. Why Is Syphillis on the Rise?
- 10. Ideal Weight vs. Happy Weight
The material on the QualityHealth Web site is for informational purposes only, and is not a substitute for medical advice, diagnosis, or treatment provided by a physician or other qualified health provider. See additional information.