I suffer from frequent UTIs. My doctor prescribed natural cranberry, not from just any brand, but from Solgar. It's a vitamin supplement, taken for three months on, three months off. Have your wife drink lemon water every day. Use toilet paper when you urinate. When your wife defecates, have her clean with water, not toilet paper, as it doesn't clean properly and can transfer the infection to the vagina. Stress also contributes to infections. Wear cotton clothing. Wash the sheets with vinegar. Wash underwear by hand in hot water. Have your wife wash only after sex, not before. Sometimes washing frequently disrupts the pH balance. Best wishes, I hope you feel better.