Ingestion of a small amount of ocean water usually leads to mild episodes of diarrhea and isn’t considered an immediate medical emergency for dogs. However, drinking large quantities of ocean water is potentially very dangerous for dogs, as it throws their electrolyte balance into disarray. If you ever suspect that your dog has ingested too much ocean water, seek prompt veterinary care. You should also seek prompt veterinary care if your dog shows signs of muscular twitches, weakness, lethargy, vomiting and prolonged diarrhea episodes (more than 2 days) after a visit to the beach.