Can a UTI go away on its own (without antibiotics)?

The short answer is maybe, sometimes. A UTI is a bacterial infection, which means antibiotics will usually help eliminate it faster than no treatment at all. One study looking at people who took ibuprofen for the first couple days of an uncomplicated UTI showed that more than half of them were asymptomatic by day four. This implies that watchful waiting for the first two or three days–in the absence of symptoms like high fever or flank/back pain–may not be too risky, especially if you are able to drink plenty of water to help dilute and flush the bacteria from the urinary tract. 

Symptoms that persist or worsen past three-to-four days, however, should probably be treated with antibiotics. If left untreated, some of these infections can progress beyond the bladder and into the kidneys. A severe kidney infection sometimes requires hospitalization for IV antibiotics. 

It’s important to note that if you’ve never had a UTI before, are not sure if you have one, or have symptoms that last longer than a day or are severe, you should contact a healthcare provider without hesitation.