THROUGHOUT the year we are called upon to treat pets suspected or known to have eaten some poisonous substances.

Unfortunately often we do not have antidotes for the commonest poisonous substances, but we can help your pet fight the effects of the various poisons.

If you think that your pet has eaten something poisonous, then please telephone your vet immediately. If it is less than two or three hours since the substance was eaten, then the vet may well help your pet to vomit up the substance – we usually have a few crystals of washing soda. If you choose to do this yourself be very careful – many products contain caustic soda which will matters worse.

The commonest "poisons" will be discussed over the following weeks but with Christmas looming, the first and often overlooked product is CHOCOLATE!

The toxic component of chocolate is therbromine (and to a lesser extent caffeine), which is found in cocoa. Fortunately much British chocolate is relatively low in cocoa.

The signs of chocolate poisoning are slow to develop, usually taking four to 24 hours to develop, and include vomiting (with or without blood), increased thirst, restlessness, inco-ordination, and increased salivation.

Untreated, this can lead to convulsions, heart failure and eventually death. However, chocolate dog treats are safe but please keep to a minimum to avoid obesity problems!

How much chocolate is toxic?

This depends on the type of chocolate, but for an average Spaniel sized dog the following amounts of chocolate would put your pet at risk: white chocolate 22kg; milk chocolate 100g or 4oz; plain chocolate 2.5-45g, ie as little as a teaspoon of high cocoa dark chocolate.

What are the chances of recovery?

Good – based on my own experience! As an impoverished veterinary student, my wife and I thought that we would treat ourselves to a family-sized Cadburys dairy milk chocolate bar. However, our Cairn Terrier pup had other ideas and scoffed the lot.

Fortunately, she made a full recovery apart from indigestion and a diet of lentils for several weeks until we had paid the vets' bill!

With prompt treatment the chances of your pet making a full recovery are good, but do telephone your vet for advice – we are available 365 days of the year, and if you do have any problems I am personally on duty answering the telephone on Christmas Day albeit with a very excited family in the background!

Beware of Neurofen (ibuprofen) and aspirin.

I include these because over the holiday period it can be tempting to give your pet a pill from the medicine cupboard if it is off colour. Quite simply NEVER give dogs or cats ibuprofen and never give aspirin to cats. Both are incredibly toxic and can rapidly cause kidney failure.

One aspirin can be fatal to cats, and two Ibuprofen can be fatal to dogs.

The safest advice is to avoid non-veterinary products altogether, but if you do feel that you want to give something that you have in your "medicine cupboard" then ring your vet for advice first.