Urine has an odor. It's often mild and hard to notice. Certain conditions, however, can cause urine to smell different. The odor might cause worry about a problem or illness.
Urine is made up mostly of water. But it also has waste in it that comes from the kidneys. What is in the waste and how much there is causes urine odor.
Urine with a lot of water and little waste has little to no odor. If urine has a lot of waste with little water, also called concentrated, it might have a strong odor from a gas called ammonia.
Some foods and medicines, such as asparagus or certain vitamins, can cause urine odor, even in small amounts. Sometimes, urine odor points to a medical condition or disease, such as:
Most changes in urine odor are temporary and don't mean you have a serious illness, particularly if you have no other symptoms. When an unusual urine odor is caused by an underlying medical condition, there are other symptoms too. If you're concerned about the odor of your urine, talk to your doctor.
Show References
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- Symptoms & causes of kidney infection (pyelonephritis). National Institute of Diabetes and Digestive and Kidney Diseases. https://www.niddk.nih.gov/health-information/urologic-diseases/kidney-infection-pyelonephritis/symptoms-causes. Accessed April 11, 2023.
- Bacterial vaginosis (BV). Centers for Disease Control and Prevention. https://www.cdc.gov/std/bv/stdfact-bacterial-vaginosis.htm. Accessed April 11, 2023.
- Smelly urine. National Health Service. https://www.nhs.uk/conditions/smelly-urine/#:~:text=If%20you%20have%20other%20symptoms,2%20diabetes%20or%20kidney%20stones. Accessed April 11, 2023.
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Original article: https://www.mayoclinic.org/symptoms/urine-odor/basics/when-to-see-doctor/sym-20050704