 [ Symptoms ] i started having severe pain in my lower back and left side abdomen just under my bottom rib should my doctor do other tests [ Disease ] chemotherapy knocks out the saliva glands saliva lubricates the teeth and protects against acid decay and gum disease when the saliva is diminished bacteria can run wild and cause the symptoms you described see a dentist asap because there are solutions salivary stimulants extra artificial saliva and fluoride supplements can all be excellent aides in combating your problems