I am having some diarrhea. What to do to make it stop?

Possibilities... First define the problem (soft or frequent stool?), circumstances under which diarrhea develops (malabsorption, pancreatic maldigestion, food intolerances, stressful times, exposure to ill individuals/infections, food poisoning, ischemic gut, inflammatory colitis, etc.), severity (stool volume, dehydration, blood, night-time awakening, weight loss), ; duration. The "cure" depends on the above.