Written By: Manasi Ambre, BPharm
Reviewed By: Pharmacally Editorial Team
Urinary tract infections (UTIs) are among the most common bacterial infections, particularly in women. Antibiotics such as nitrofurantoin remain the cornerstone of treatment. Alongside antibiotics, patients are often advised to drink more water. This advice is common, but its scientific role is often misunderstood.
What is a Urinary Tract Infection (UTI)?
A urinary tract infection (UTI) is a bacterial infection that affects any part of the urinary system, most commonly the bladder. It occurs when bacteria, usually from the gut, enter the urinary tract and multiply. Typical symptoms include a burning sensation during urination, frequent urge to urinate, cloudy or strong-smelling urine, and lower abdominal discomfort. UTIs are typically treated with antibiotics, while supportive measures such as adequate hydration are often recommended to help relieve symptoms and support recovery, a role we will discuss in more detail further in this article.
Why hydration matters during a UTI
Hydration does not treat the infection directly, but it plays a supportive role during recovery.
Adequate fluid intake increases urine output, which flushes bacteria, inflammatory debris, and bacterial by-products from the bladder. This can reduce urinary irritation and ease symptoms such as burning and urgency.
Diluted urine is also less irritating to an inflamed bladder lining, which may improve comfort during urination.
Does drinking water affect how antibiotics work?
A common concern is whether drinking more water might “flush out” antibiotics, such as nitrofurantoin. Evidence does not support this idea.
Nitrofurantoin is rapidly absorbed from the gut and then concentrated in the urine, where it exerts its antibacterial effect. Normal hydration does not reduce its effectiveness. In fact, proper kidney function and urine flow are essential for the drug to reach the urinary tract in effective concentrations.
How much water is enough?
There is no fixed volume recommended specifically for UTIs.
A practical approach is
- Drink fluids regularly throughout the day
- Aim for pale yellow urine, which suggests adequate hydration
- Avoid forcing excessive amounts of water, as this can increase discomfort and urinary frequency
Patients with heart failure, kidney disease, or fluid restrictions should follow medical advice tailored to their condition.
What can hydration not do?
It is important to set realistic expectations:
- Hydration cannot replace antibiotics
- It does not eliminate bacteria on its own
- It does not shorten treatment duration if antibiotics are stopped early
Completing the full prescribed antibiotic course remains essential, even if symptoms improve.
Hydration supports UTI treatment by improving urinary flow, reducing irritation, and aiding symptom relief. Antibiotics clear the infection, while water helps the urinary system recover more comfortably and efficiently. Used together, they form a practical and evidence-based approach to UTI care.
References
McCollum BJ, Garigan T, Earwood J. PURL: Can drinking more water prevent urinary tract infections? J Fam Pract. 2020 Apr;69(3):E19-E20. PMID: 32289134; PMCID: PMC7271893.
Hooton TM, Vecchio M, Iroz A, et al. Effect of Increased Daily Water Intake in Premenopausal Women with Recurrent Urinary Tract Infections: A Randomized Clinical Trial. JAMA Intern Med. 2018;178(11):1509–1515. doi:10.1001/jamainternmed.2018.4204
Dr. Ranjan Bansal, The Role of Diet and Hydration in Preventing Urinary Tract Infections (UTIs), Institute of Urology, 26 May 2025, https://www.instituteofurology.in/the-role-of-diet-and-hydration-in-preventing-urinary-tract-infections-utis/
Anna Mae Scott et al, Increased fluid intake to prevent urinary tract infections: systematic review and meta-analysis, British Journal of General Practice, March 2020