Dogs love to frolic in the ocean, but salt water is toxic to humans and dogs if they drink too much. Ocean soaked tennis balls or other absorbent fetch toys contain enough salt to cause problems for the dogs that are fetching them. Mild ingestion of salt water can cause “beach diarrhea.” The excess salt (or hypernatremia) in the intestines draws water from the blood into the intestines, causing the diarrhea.
The diarrhea can sometimes contain blood and mucous. If your dog drinks large amounts of salt water, hypernatremia can lead to vomiting, dehydration, incoordination, seizures, and require veterinary care. Avoid salt poisoning by taking a break every 15 minutes away from the water to offer fresh water to the dog. If your dog won’t drink willingly, use a bottle with a sports cap and squirt fresh water into the mouth.
Water activity is great for dogs and the exercise far outweighs the risks, but it is important to be mindful of the risks in the water you dog so dearly loves.