It can be upsetting to see a beloved pet behaving in a way that seems gross or bizarre. Occasionally a dog will drink its own urine, much to its owner's mortification. This is not a sign of abnormality in the dog. Dogs, as they say, will eat just about anything. If a piece of rotting meat or old garbage won't repel a dog, its urine won't either. If your dog displays an interest in its urine, you must simply teach it that this is forbidden, as you would regarding old garbage.
There are differing theories as to why exactly dogs drink their own urine. One prevalent theory is that the dog is lacking nutrients and trying to make up for them. While this has not been proven, it is worth considering, especially if you have an older dog whose habits you are familiar with. Vitamin supplements might help, and a check-up with the veterinarian would be prudent.
While it is not really healthy for your dog to drink its urine, it is likewise not really harmful. Urine is different than feces in that it is sterilized in the digestive system. You don't have to worry about your dog becoming ill from drinking its urine. You only need to worry about proper training.
Your dog could be drinking its urine simply because it smells interesting. Its urine is a curiosity, like a newspaper or a pair of slippers. A firm "No!" and a mild form of punishment such as time-out should (over time) be enough to stop the behavior. Your dog might also be drinking its own urine due to a urinary tract infection, in which case a trip to the vet is necessary.
Is your dog housebroken? A housebroken dog is less likely to drink its urine than a dog that isn't housebroken. One reason is that urine doesn't absorb into linoleum, tile or finished wood like it does into dirt, grass and concrete. It remains pooled on the floor, tempting the dog's curiosity. Another reason is that, while a dog may not be housebroken, it may still know that urinating inside is forbidden. It will lap up its urine to hide the evidence.
Training a dog is largely a matter of time and patience. You must get to know your dog; knowing its habits, mannerisms, moods and methods will keep you a step ahead, building your confidence and your dog's respect. Teach your dog basic manners and other manners will follow. Always remember that you have a great friend in your veterinarian, no matter how small or embarrassing your concerns may seem to you.