Puppies should have soft stools for the first five weeks of their lives, which their mother will eat. At five weeks, puppy stool should become harder and should resemble adult dog stool. If at any time there is rectal bleeding or blood in a puppy's stool, you can be sure there is something wrong with your puppy. The best course of action is to seek a vet's counsel right away, but there are some home strategies you can try, as well.
Check for worms in your puppy. The Kennel Club organization says that worms are the number one cause of painful stools and bloody stools. In some cases, you can see the worms in the stool along with the blood. Some worms, like hook worms, might be invisible if they are not very big. Ask your vet to check for worms or give your puppy an over-the-counter worm medication. Once he has normal stools, he should not have any other blood in his stool. You can worm your puppy at home and watch for his stools to return to normal, if that is the cause of the bleeding.
Understand that viruses, like parvovirus, can cause blood in stools. The only way to check for viruses like parvo is to ask your vet to test your puppy. There are no home remedies for parvo and there is no home cure for parvo. Parvovirus can kill your puppy if it is not treated. Take your puppy to the vet to rule out parvovirus before you try any other home remedies for rectal bleeding.
Check your puppy's stool for strange food or objects. If you can see bits of wood, it might mean that your puppy has eaten something that is causing injury to his digestive track. If you can see plastic or other material, there might also be injury. Although the home remedy for this type of injury is to wait it out and see if he passes the objects and the bleeding stops, the injury might cause extreme damage to him in the time it takes to wait it out. The best bet is to skip the home remedy and take him to a vet for an examination.
If your puppy is not passing any stool, but is only passing blood, do not waste time trying any home remedies. Take him to the vet immediately, as his life might be threatened by a blocked colon, a bowel obstruction, or a severe virus.