Symptoms of heat stress in dogs include panting, vomiting, diarrhea, dehydration, and absence of urination. The body temperature can reach 41 degrees Celsius, reflecting harmful changes to internal organs. To reduce the body temperature, immerse the animal in cool water and monitor its temperature regularly, providing remedies every 10-15 minutes initially such as Aconite for intense thirst and restlessness or Apis for a congested face and head rolling. If the animal does not improve with treatment, seek immediate veterinary care as heat stroke can have dire consequences. Prevention is easier than treatment for heat stress.