I have had diarrhea for the past 4 days at times have felt a bit nauseas and experienced a slight headache on the 4th day. mouth very dry. not surewhy?

Dehydration: You are dehydrated and need to drink lots of water and/or an electrolyte drink like Gatorade. If you still have diarrhea, it is time to see a doctor. Wish you good health! - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex, if you have sex.