Urine consists mainly of water. It's the amount and concentration of various waste products excreted by the kidneys that causes urine odor.
Urine that contains a lot of water and few waste products has little to no odor. If urine becomes highly concentrated — a high level of waste products with little water — your urine may have a strong ammonia odor.
Some foods and medications, such as asparagus or certain vitamins, can cause a noticeable urine odor, even in low concentrations. Sometimes, unusual urine odor indicates a medical condition or disease, such as:
- Bladder infection
- (bladder inflammation)
- (high levels of blood acids called ketones)
- Gastrointestinal-bladder fistula (abnormal connection between the intestines and bladder)
- Maple syrup urine disease (rare genetic disease that causes difficulty breaking down certain amino acids)
- Metabolic disorder (a problem with the way your body converts the foods you eat into energy)
- Type 2 diabetes (uncontrolled)
- Urinary tract infection (UTI)
Aug. 25, 2016
Causes shown here are commonly associated with this symptom. Work with your doctor or other health care professional for an accurate diagnosis.
- Brunzel NA. Physical examination of urine. In: Fundamentals of Urine and Body Fluid Analysis. 3rd ed. St. Louis, Mo.: Saunders Elsevier; 2013:97.
- McPherson RA, et al., eds. Henry's Clinical Diagnosis and Management by Laboratory Methods. 23rd ed. St. Louis, Mo.: Elsevier; 2017. https://www.clinicalkey.com. Accessed Aug. 10, 2016.
- Shirasu M, et al. The scent of disease: Volatile organic compounds of the human body related to disease and disorder. The Journal of Biochemistry. 2011;150:257.
- Chernecky CC, et al., eds. Urinalysis. In: Laboratory Tests and Diagnostic Procedures. 6th ed. St. Louis, Mo.: Saunders Elsevier; 2013. https://www.clinicalkey.com. Accessed Aug. 11, 2016.
- Wilkinson JM (expert opinion). Mayo Clinic, Rochester, Minn. Aug. 13, 2016.