What medicine should I give?

Goat loose motion needs rehydration first, not random medicine. Give clean water with oral rehydration salts, keep only dry fodder for now, and avoid green grass, kitchen waste, and sudden feed change. If the goat is still eating and active, this often settles in a day. If there is fever, blood in dung, sunken eyes, or weakness, it is likely an infection and your vet will need to prescribe the right treatment. Treating it early saves the goat from dehydration and loss of condition. Consult a veterinarian before administering any medicine or treatment.