In modern society, preventive medication is undoubtedly a better approach than curative medication when the disease is not yet present. In addition to prevention in life, preventive medication is also an important part of the process, especially for the disease’s susceptibility and prevalence, preventive medication should be administered in the following cases: 1. Short-term preventive medication during menstruation, pregnancy, and when women are overly tired or have reduced resistance can often play a preventive role. It is worth noting that pregnant women before 16 weeks and after 30 weeks should avoid sulfonamides. Prophylactic medication can be administered with furantoin 50 mg, taken every night until after delivery. 2. For female patients with recurrent episodes related to sexual intercourse, urinate immediately after sexual intercourse and take one oral dose of antibacterial medication for prophylaxis at the usual dosage. Better if taken before sex. According to Asscher statistics, the effective rate is 80%. Stamey believes that female patients with recurrent episodes may be related to their spouse’s overcircumcision and should advise their spouse to correct it. 3, in women with frequent urinary tract infections, even if their episodes have little to do with sexual intercourse, if you can take a dose of antibacterial drugs every night for prevention, can also greatly reduce the occurrence of urinary tract infections. 4. Before urinary tract instrumentation examination, it is advisable to take an oral antimicrobial drug for prevention, especially for those who have a history of recurrent urinary tract infections or urinary tract abnormalities, it is advisable to take antimicrobial agents 48 hours before and after the urinary tract mechanical examination to prevent infection. In the first 3 days of indwelling catheterization, giving antibacterial drugs can prevent or delay the occurrence of urinary tract infection. 5. For people with recurrent urinary tract infections, prophylactic therapy can be used after sterile urine cultures. Recently, it has been reported that taking 50mg of furantoin at bedtime is extremely effective, or 100mg of sulfonamide booster, 0.48g of cotrimoxazole, or 0.2g of haloperidol. If the patient is a renal insufficiency, he can take 1g of oral urotropine and 0.125g of cephalexin. Foreign data prove that furantoin a dose of 0.05 grams or 0.1 grams is extremely effective. Moreover, the drug does not lead to dysbiosis of intestinal flora and does not promote the occurrence of bacterial resistance. The advantage of sulfonamide booster as a prophylactic agent is that it is partially excreted vaginally, which helps in the prevention of urinary tract infections in sexually active women. Generally, people do not urinate after sleep, and urine stays in the bladder for a long time, which is conducive to the growth and reproduction of bacteria. Therefore, taking a dose of antibacterial drugs before going to bed can inhibit the growth of bacteria, which has a good preventive and therapeutic effect on urinary tract infections. Clinical observation, overnight dosing, or three times a week dosing, or after sexual intercourse once a dose of medication, the effect is similar to nightly dosing. 6. For older women with recurrent urinary tract infections, treatment with oral or topical estrogen should be considered as early as possible. Estrogen can promote glycogen accumulation in vaginal epithelial cells, enable the growth of Lactobacillus and produce lactic acid to acidify vaginal secretions, thus inhibiting the growth of potentially pathogenic bacteria in the vagina in the elderly.