Bladder infections in otherwise healthy pre-menopausal and non-pregnant women tend to be uncomplicated and are classified as lower urinary tract infections (UTIs). UTIs are amongst the most common infections in women and Escherichia coli (E.coli) is the organism that is the most common, responsible for about 75-95% of uncomplicated UTIs.
Trimethoprim/sulfamethoxazole (TMP/SMX), aka co-trimoxazole, and brand names, Bactrim or Septra, is an inexpensive antibiotic and generally well tolerated and effective. However, due to its common use, resistance to E. coli strains with this antibiotic has increased significantly, and as many as 20% of cases will be resistant, which is why other first line antibiotics are often chosen.
The genesis of this current study is that there are laboratory studies that have shown antimicrobial effects of green tea catechins against E. coli as well as synergistic effects between the catechins and antibiotics such as the co-trimoxazole against E. coli.
This randomized, blinded, placebo-controlled trial was conducted in Iran. Healthy premenopausal, non-pregnant women ages 18-50 with acute uncomplicated cystitis were included in the study. After urine collection, women were given four 500 mg capsules of green tea extract or placebo before bed, daily for 3 days. All of the patients also received the TMP/SMX at two 480 mg tablets twice daily for 3 days. Each gram of the green tea contained approximately a total phenol content of 283 mg and 65 mg of epigallocatechin (EGC). The urine was then tested again in each group, on the fourth day.
Results: Among the 107 eligible women patients, 70 completed the trial. Women in the green tea group showed a statistically significant decrease in the prevalence of cystitis symptoms at each time point (recorded daily). The presence of symptoms was as follows:
Baseline: Green tea 68%; placebo 75%
After 1 day Green tea 61%; placebo 74%
After 2 days Green tea 34%; placebo 67%
After 3 days Green tea 2%; placebo 63%
In addition, the addition of the green tea resulted in a statistically significant improvement in the urinalysis in terms of color, bacteria, and white blood cells. No patients, in either group, had a recurrence of their UTI after 2 weeks. After 4 weeks, 1 in the green tea group had a recurrence and after 6 weeks, 2 in the TMP/AMX only group had a recurrence.
Commentary: One of the unique things in the study design was that the green tea extract was given in a bolus, all four capsules at once, and in the evening. The rationale of the researchers was that the EGC was better retained in the bladder all night, noting that more than 90% of the urinary EGC is excreted in the first 8 hours of administration, therefore all at once and in the evening before bed would theoretically enhance its effectiveness, if they did not urinate until morning.
In my experience, 49 out of 50 premenopausal non-pregnant women with uncomplicated UTIs can be successfully treated with a combination of herbal ingredients if dosed aggressively (formulas typically would contain cranberry extract, buchu leaf, Oregon grape root, pipsissewa, uva ursi and marshmallow root); occasionally I might add mannose powder, along with robust water. On the atypical occasion that I prescribe an antibiotic, I will consider adding the dosing of green tea extract for 3 days used in the current study, whether the antibiotic is TMX/SMP or another.
Reference: Kheirabadi K, Mehrabani M, Sarafzadeh F, et al. Green tea as an adjunctive therapy for treatment of acute uncomplicated cystitis in women: A randomized clinical trial. Complementary Therapies in Clinical Practice 2019;34:13-16
