Puppies get into everything, so get as many potentially harmful things out of their reach as you can. While a small amount one time may not hurt him, small amounts over time or a large amount just once, can and probably will -- so keep puppy treats with garlic off your shopping list. Knowing your pup’s normal behavior patterns and personality helps you catch potential poisonings quickly.
If your puppy eats enough garlic, at a minimum he’ll likely get painful gastroenteritis -- a tummy ache. The more serious poisoning causes hemolytic anemia. In his body’s attempt to get rid of the toxic ingredient in the garlic, called n-propyl disulfide, it actually starts a series of events that ends up destroying his red blood cells -- the hemolysis. If this process continues without being arrested or treated, he'll no longer have enough red blood cells to carry the oxygen he needs to maintain a normal activity level, and eventually, to live.
Symptoms of Gastroenteritis
Your puppy will have several bouts of vomiting and diarrhea if the gastroenteritis is severe. Also look for signs of gagging or heaving after eating or drinking water. Touch his tummy and his hind end; if he reacts like its sensitive, that’s another sign of painful inflammation in his stomach. He may or may not continue to eat, and could run a fever.
If he has a minor case, he may just not seem hungry and will be less playful and active than normal.
Symptoms of Hemolytic Anemia
If your puppy is tired and just not himself, that’s your signal to watch him closely for more concrete signs of something wrong. Check if his gums are pale and if you can, observe his urine to detect a reddish tint to it. If he seems weak and is eating less or not at all, those are also signs of hemolytic anemia. He may also have gastroenteritis in addition to hemolytic anemia, so those symptoms can be present together.
There is another form of hemolytic anemia called immune-mediated hemolytic anemia. This is not caused by poisoning, but is likely an inherited condition that is more prevalent in some breeds but not others.
What To Do
As soon as you know that your puppy ate garlic, call your veterinarian or a pet poison control center. The APSCA has a poison control center hotline you can call at 888-426-4435. Be aware that you need to pay a fee to get their counsel on your puppy’s case; as of July 2013 the fee is $65.
If you didn’t catch him eating the garlic and just start to notice symptoms, he could have eaten the garlic days earlier -- it can take two to four days before any symptoms set in. Remember that if he is vomiting or has diarrhea for more than 24 hours he risks becoming dehydrated, so call your veterinarian. She can do a blood test to determine if he does in fact have hemolytic anemia. As long as he is no longer consuming garlic and is otherwise healthy, he has a good chance of completely recovering with some rest. If too much damage has been done, he may need a blood transfusion.