Is doxycycline (antibiotic) effective for treating chronic Urinary Tract Infections (UTI)?

From the Guidelines

Doxycycline is not the preferred treatment for chronic UTI due to its limited effectiveness against common uropathogens and potential for resistance. The European Association of Urology guidelines on urological infections, as outlined in the 2024 guidelines 1, emphasize the importance of appropriate management of underlying complicating factors and optimal antimicrobial therapy based on the severity of illness, local resistance patterns, and specific host factors. For chronic UTIs, antibiotics such as trimethoprim-sulfamethoxazole, nitrofurantoin, or fluoroquinolones are generally preferred because they achieve higher concentrations in the urinary tract and target common uropathogens more effectively. When considering doxycycline for UTIs, it's crucial to note that its use is typically reserved for cases where the causative organism is specifically susceptible to doxycycline or when first-line options cannot be used. The recommended treatment duration for chronic UTI is generally 7-14 days, depending on the severity of the illness and the treatment of the underlying abnormality 1. Key factors to consider in the management of chronic UTI include:

• Identifying underlying causes such as anatomical abnormalities
• Proper hygiene practices
• Adequate hydration
• Possibly prophylactic antibiotics at a lower dose for prevention
• Urine cultures to identify the specific bacteria causing the infection and its antibiotic susceptibilities to guide appropriate treatment. The microbial spectrum of chronic UTI is broader, and antimicrobial resistance is more likely, making it essential to choose an antibiotic that is effective against the specific uropathogen isolated 1.

From the FDA Drug Label

Doxycycline is indicated for treatment of infections caused by the following gram- negative microorganisms, when bacteriologic testing indicates appropriate susceptibility to the drug: ... Respiratory tract and urinary tract infections caused by Klebsiella species. Doxycycline is indicated for treatment of infections caused by the following gram-positive microorganisms when bacteriologic testing indicates appropriate susceptibility to the drug: ... Upper respiratory infections caused by Streptococcus pneumoniae Uncomplicated urethral, endocervical, or rectal infections in adults caused by Chlamydia trachomatis. Nongonococcal urethritis caused by Ureaplasma urealyticum.

Doxycycline may be used for the treatment of urinary tract infections (UTIs) caused by susceptible bacteria, such as Klebsiella species, Chlamydia trachomatis, or Ureaplasma urealyticum. However, the label does not specifically address chronic UTI. Key points to consider:

• The drug label indicates doxycycline is used to treat UTIs caused by specific bacteria.
• Bacteriologic testing is recommended to ensure the bacteria are susceptible to doxycycline.
• The label does not provide information on the treatment of chronic UTI specifically 2.

From the Research

Doxycycline for Chronic UTI

• Doxycycline has been shown to be effective in treating chronic UTIs, particularly in cases where other antibiotics have failed 3.
• A study published in 2017 reported a case of a patient with a multidrug-resistant UTI who was successfully treated with oral doxycycline hyclate 3.
• The advantages of doxycycline for UTI treatment include its oral formulation, wide spectrum of activity, ability to achieve high concentration in the urine, and low toxicity 3.
• Another study published in 2004 found that treatment with doxycycline was effective in 71% of women with chronic urethral and/or pelvic pain, and dyspareunia, as well as a history of recurrent UTIs 4.

Antimicrobial Susceptibility Patterns

• A study published in 2018 evaluated the antimicrobial susceptibility patterns of Escherichia coli in children and adults with UTIs, and found that E. coli was highly susceptible to levofloxacin and gatifloxacin, but had low susceptibility to amoxicillin/clavulanic acid 5.
• The study also found that the susceptibility of E. coli to cephalosporins ranged from 34.09% to 65.91% in children, and from 65.91% to 80.00% in adults 5.
• Another study published in 2018 found that fluoroquinolones, nitrofurantoin, and trimethoprim-sulfamethoxazole were the most commonly prescribed antibiotics for UTIs, but that fluoroquinolone use decreased from 2015 to 2019, while nitrofurantoin and beta-lactam use increased 6.

Treatment Guidelines

• The Infectious Diseases Society of America recommends nitrofurantoin, trimethoprim-sulfamethoxazole, and fosfomycin as first-line antibiotic treatments for uncomplicated UTIs, and discourages the use of fluoroquinolone antibiotic agents 6, 7.
• A study published in 2021 found that guideline concordance for UTI treatment increased from 48.2% in 2015 to 64.6% in 2019, but that fluoroquinolone use remained high, and that actions such as educating physicians about antibiotic resistance and clinical practice guidelines are needed to increase guideline concordance 6.
• Another study published in 2018 found that urine culture is the gold standard for detection of UTIs, and that first-line treatments for UTIs include nitrofurantoin, fosfomycin, and trimethoprim-sulfamethoxazole (when resistance levels are <20%) 7.