A bladder infection is a bacterial infection of the urinary tract, often called a urinary tract infection (UTI). More common in women than in men, it is usually quickly and easily treated with a course of antibiotics, but if left untreated, it can be very dangerous. Infections are not transmitted from person to person, and people usually get one from bacteria that is naturally in or on the body — most often E. coli, which lives in human feces. Still, sexual activity often triggers a bladder infection, and some old-school medical professionals might still refer to it as the "honeymoon disease," since new brides often acquired one on their honeymoon.
The first sign of this infection is the person feeling that she needs to urinate, yet she produces little urine and the "full" feeling doesn't go away. This should be the first sign for a patient to go see a healthcare practitioner for antibiotics, because ignoring the symptoms will only cause further pain. An untreated bladder infection will result in painful urination or the inability to urinate at all.
Eventually, an untreated bladder infection will reach the kidneys. A kidney infection is nothing to fool around with — the pain alone will drive most people to the nearest medical professional. Kidney infections can be accompanied by dangerously high fevers and can lead to permanent kidney damage, so an infection needs to be treated with the first symptoms.
Some people are prone to recurring infections. This is probably due to the size and shape of the urethra. People who find themselves getting one infection after another may need to change some habits. They should drink lots of water, as it flushes and cleans the urinary tract.
People should urinate often. Many people try to hold their urine as long as they can in the belief that this will expand their bladder and give them more control. This really isn't a good idea, and frequent trips to the bathroom will keep the urinary tract healthier in the long run.
Women may also want to consider adding cranberry juice to their diets, as it may add hippuric acid to the system, acidifying the urinary tract and making it more difficult for a bacterial infection to get started. There is some debate among researchers about how effective this proactive treatment is, but it's unlikely to do any harm. Women who do want to consume cranberry juice must make sure to use pure juice, however, and not juice cocktail, which is diluted and contains too much sugar. People who don't want to drink cranberry juice may want to try cranberry in pill form, which is often available at health food stores.