Brief Answer:
Probiotics, Zinc, Calcium

Detailed Answer:
Hi there,

I would recommend starting with a probiotic, multivitamin, zinc, and calcium supplements. Avoid all magnesium containing supplements as these can worsen symptoms. Some people get relief from the traditional bananas, rice, applesauce, toast (BRAT) diet despite its little evidence-based support and lack of nutrition. During periods of active gastroenteritis, coffee, alcohol, dairy products, fruits, vegetables, red meats, and heavily seasoned foods may exacerbate symptoms. I would also recommend drinking plenty of fluids.

If it continues I would recommend:
-A colonoscopy: alternating or change in bowel habits without change in your diet is strongly related to colon cancer, especially at your age. A colonoscopy can also help diagnose diseases such as Crohn's, Celiacs, Ulcerative colitis, or Microscopic colitis.
-Complete routine screening blood work for infections, anemia, and inflammatory processes, as well as electrolytes, glucose, kidney function, thyroid function, liver function, pancreatic function, and vitamin deficiencies. Also test for H. Pylori bacteria.
-Urinalysis for infection and kidney disease
-Stool studies for infection and inflammatory bowel diseases
-Pelvic Ultrasound looking for masses or abnormalities
-Endoscopy looking for ulcers and masses, as well as inflammatory disease.
-If you are having fevers or bloody bowel movements, I would see a medical professional within a couple days.

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