Treatment is directed at the cause. Many clinicians do not treat dysuria in women without red flag findings if no cause is apparent based on examination and the results of a urinalysis. If treatment is decided upon, a 3-day course of trimethoprim/sulfamethoxazole or trimethoprim alone is recommended. Because they can cause tendinopathy, fluoroquinolones should not be used for uncomplicated urinary tract infections (UTIs) whenever possible. Some clinicians give presumptive treatment for a sexually transmitted disease (STD) in men with similarly unremarkable findings; other clinicians await STD test results, particularly in reliable patients. Acute, intolerable dysuria due to cystitis can be relieved somewhat by phenazopyridine 100 to 200 mg orally 3 times a day for the first 24 to 48 hours. This drug turns urine red-orange and may stain undergarments; patients should be cautioned not to confuse this effect with the progression of infection or hematuria. Complicated UTI requires 10 to 14 days of treatment with an antibiotic that is effective against gram-negative organisms, particularly Escherichia coli.