An urgent warning has been issued to pet owners over an ingredient in common household foods which can be deadly for dogs. 

The RSPCA has shared its advice to pet owners about xylitol - also known as E967 - a low-calorie sweetener, which is poisonous to dogs.

Xylitol is a natural sugar found in plants, fruits and vegetables that is used as an alternative to sugar due to having 40pc fewer calories and a low glycemic index.

It can be found in sugarless gum and other sugar-free products but has also been used in some brands of peanut butter which dog owners often give as a treat or to administer medication. 

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An RSPCA spokeswoman said: "While many pet owners are aware of the more common dangers to their pets - like chocolate or onions - some poisons are less well known.

"Xylitol can be extremely hazardous to dogs because it can cause a very rapid drop in blood sugar and later there is the risk of liver damage.

"Symptoms can come on within an hour of ingestion, although in some cases there can be a delayed onset of 12 hours."

A sudden drop in blood sugar can cause hypoglycaemia - resulting in vomiting, seizures, mobility issues, comas and even death. 

Other common products that may contain xylitol include mints, toothpaste, allergy medicines and digestive aids.

The spokeswoman added: "It is a secret poison as many people just aren’t aware of the dangers - so it's really important pet owners are aware and help us spread the message as to the dangers of xylitol to dogs.

"Always check the ingredients of anything you feed your pet and if you think your pet has eaten something they shouldn’t have then you should ring your vet straight away.”