Monthly Archives: March 2016


Chocolate Poisoning in Pets

With Easter around the corner and the chocolate shopping increasing in the run up to Easter, I thought of writing a short article on chocolate poisoning.  The VPIS (Veterinary Poison Information Service) wrote an article at the end of last year about the revised treatment doses for chocolate.  This is what they wrote:

“We have recently reviewed and revised our treatment doses for chocolate. The revised doses are based on case data analysis (of over 700 cases where the dose of chocolate eaten was estimated or known) and analysis of original sources where the theobromine content of chocolate products was measured.

Toxic effects in dogs occur at theobromine doses of 20 mg/kg, with severe signs at 40-50 mg/kg and seizures at 60 mg/kg.

We now recommend the following:

treat for > 3.5 g/kg for dark chocolate
treat for > 14 g/kg for milk chocolate
White chocolate is very low in theobromine and is not likely to cause theobromine toxicity.

It is also worth noting that the amount of theobromine in products varies due to natural differences in cocoa beans and the formulation of products, and that there may be some genetic susceptibility to theobromine toxicity in some dogs. In addition, approximately half of the cases reported to us remain asymptomatic.

Although chocolate can make dogs unwell, it is very rarely fatal; indeed, out of the 1,000 canine cases with follow up on our database, we have only recorded 5 fatal cases. We are however aware that numerous cases of chocolate toxicity go unreported.”

So if your pet ends up stealing and eating chocolate, the amounts above give you an indicator whether a vet visit is due or not.  With large amounts ingested I would recommend that your vet is contacted as the theobromine in the chocolate can cause seizures.

Tick mouth

Ticks and Tick-Borne Diseases in the UK

The news hit the Vet Times about a week ago and the media today that there are new tick-borne diseases discovered in the UK, which hadn’t been seen in pets before.

The discovery was made in the South of the UK.  The link to the website with the news is here.

Those pets in which the disease had been discovered didn’t travel abroad and somehow still contracted a tick-borne disease previously not seen in the UK.

Last year, MSD asked vets around the country to collect ticks from dogs and send them to Bristol Veterinary University.  The purpose was to study the diseases the different types of ticks were carrying and to get a distribution map for the UK.  Bristol University became overwhelmed with a large number of ticks sent to them by vets all over the country and the research is still ongoing.  They anticipate to publish their findings sometime in summer 2016.

MSD also provided vets with a video link to educate clients on what ticks carry, what they do, where you find them, how they transmit, how to find them on your pet and in which way they can make your pets ill with the diseases they carry (previously mainly Lyme disease) and how they even can make humans ill by passing on Lyme disease.  The video link can be accessed here.

For more information on the Big Tick Project by MSD, click here.


The VPIS is aware that there are several garlic supplements available and marketed for use in dogs. However, based on animal studies and our past cases, there is evidence to suggest garlic is toxic to dogs. Therefore we would not recommend it is included in their diet unless it is in the form of a licenced or approved medicine or supplement.

Garlic is a species in the onion genus, Allium, and therefore contains organosulphoxides. This group of toxins causes the depletion of the enzyme G6PD, which in turn diminishes the protective nature of the antioxidant glutathione. This causes Heinz body anaemia.

Japanese and Korean dog breeds are more susceptible due to an inherited trait causing erythrocytes with high concentrations of glutathione, which accelerates the oxidative damage caused.

The onset of clinical signs (mainly gastrointestinal) is variable, but can occur within 24 hours where a large quantity has been ingested. The main concern surrounding the ingestion of garlic is the risk of developing Heinz body anaemia.

Clinical signs asssociated with this condition include lethargy, weakness, pale mucous membranes, tachycardia (fast heart rate) and tachyponoea (fast breathing). Haematological changes may indicate oxidative damage.

Gut decontamination is recommended for any quantity ingested. If there are no risk factors, most animals can be sent home with advice to ensure adequate hydration and, if possible, to provide a high protein diet. Any symptomatic animal should be observed in practice and assessed for anaemia for at least 24 hours.