cystitis is caused by too much spicy food vinegar. coffee alchol and tea. also you should not use biological washing powder on underwear . tampax bubblebath and vaginal deodrants can also cause a flare up,,, you should drink plenty of herbal tea and barley water. you should also try to eat lots of yogurt the plain yogurt is a natural antibiotic you should also try to eat as much fresh food as possible. carrot juice would also be of benefit. vitamins a.b.c.e. and beta carotene should also be of benefit.if you wish to take herbal tablets then take echinacea abd dandelion... hope this helps mullein