Why?

Soy sauce contains approximately 900–1000mg of sodium per tablespoon — roughly 40% of the maximum daily sodium recommendation for a 30-lb dog in a single tablespoon. This extremely concentrated salt load causes rapid hypernatremia: the sodium level in the blood rises faster than the body can compensate.

High blood sodium pulls water out of brain cells, causing them to shrink. The resulting neurological effects — disorientation, tremors, seizures — can progress to cerebral hemorrhage. A 10-lb dog that laps up a small puddle of spilled soy sauce or gets into a dish at a sushi restaurant can receive a dangerous sodium dose within minutes.

The high sodium content also stresses the kidneys, which must work to excrete the excess. Dogs with any pre-existing kidney condition are at higher risk.

How much is dangerous?

A tablespoon or two of soy sauce can cause sodium poisoning in a dog under 10 lbs. The sodium concentration (5,700mg/100g) is far above safe levels.

What are the symptoms?

ONSET:Symptoms within 30–120 minutes of significant ingestion.
  • extreme thirst
  • vomiting
  • diarrhea
  • lethargy
  • tremors
  • seizures
  • coma

What should I do?

⚡

Emergency vet care. IV fluid replacement must be done carefully — too-rapid correction causes cerebral edema. Do not force-feed water.

Frequently asked questions.

My dog licked soy sauce off the floor — is that dangerous?

A very small lick (a few drops) from a spill is unlikely to cause toxicity in a large dog. More than a tablespoon, or any amount in a small dog, warrants a vet call.

Is low-sodium soy sauce safe?

Low-sodium soy sauce still contains very high sodium relative to dog safe levels. It is not safe for dogs.

Disclaimer: This information is for educational purposes only and does not constitute veterinary advice. Every dog is different. Always consult your veterinarian before making changes to your dog's diet or in the event of a potential poisoning emergency.