The Dangers of Giving Dogs Alcohol

We all know that dogs can't eat chocolate, but there are plenty of other substances that can harm man's best friend, including one of our favorite vices: alcohol.

One dog named Coco in the U.K. recently made headlines due to requiring rehab-like treatment for alcohol dependence developed as a result of its previous owner giving it alcohol, suffering from alcohol withdrawal symptoms and even having fits at times.

So what effects does alcohol actually have on dogs?

Alcoholic drinks contain ethanol, which is the active ingredient that gets you drunk. It is absorbed by the stomach and small intestine, entering the bloodstream, and leading to characteristic drunkenness, before slowly leaving the body due to being broken down by the liver, and excreted by the kidneys. However, drinking too much at once can lead to alcohol poisoning, due to blood alcohol content reaching excessive levels.

"The main risk to dogs is through acute exposure to alcohol," Harry Sumnall, a professor of substance use at Liverpool John Moores University in the U.K., told Newsweek. "Just like in humans, alcohol is toxic to all the major organs and if consumed in large volumes can lead to alcohol poisoning. We don't know whether dogs feel the same subjective mood and emotional as humans do when they consume alcohol, but other effects are similar, including vomiting, lethargy, loss of bodily control, distressed vocalization, and disorientation—which can lead to injuries. At higher doses, alcohol will lead to respiratory distress causing death."

These effects are amplified at lower doses than they are in humans, because of differences in factors such as body size, as well as the fact that alcohol is more quickly absorbed and metabolized in animals.

"The effect of alcohol on dogs is similar to that of humans in that it can cause severe poisoning," Ian Hamilton, an associate professor in addiction at York University in the U.K., told Newsweek. "However dogs process alcohol faster than humans, for humans there is a time lag between consumption of alcohol and then experiencing the effects, for dogs this can take less than 30 minutes. This faster processing of alcohol in dogs means poisoning is a significant risk even with relatively small doses."

In humans, blood alcohol concentrations of 0.31 percent to 0.45 percent are considered life-threatening, with the lethal dose of alcohol considered to be 5 to 8 grams per kilogram (g/kg), (equivalent to 0.08 to 0.128 ounces per pound), according to AddictionResource.net. The American Kennel Club states that the lethal dose in dogs is 5.5 to 7.9 g/kg (0.088 to 0.1264 ounces per pound). However, dogs weigh a lot less than humans.

"Dogs that have ingested alcohol therefore need to be carefully monitored, and veterinary support sought if the animal begins to show signs of distress," Sumnall said.

Dogs are also capable of becoming dependent on alcohol in much the same way that humans are after prolonged exposure.

"As with humans, dogs could enjoy the relaxing effect of alcohol. Associating alcohol with this feeling means that dogs can become dependent," Hamilton said. "Depending on how much and how often a dog has been exposed to alcohol will determine the degree to which they experience withdrawal symptoms if they stop being given alcohol. Symptoms of alcohol withdrawal are the easiest and most reliable way of determining if a dog has become physically dependent on alcohol."

Addiction, however, is a uniquely human affliction, as it implies not only dependence on a substance but failures to function in human life.

"Animals will not experience 'addiction' in the same ways as humans," Sumnall said. "If repeatedly exposed, they will show signs such as withdrawal or tolerance to its effects, but many diagnostic criteria of 'addiction' are uniquely human, and involve factors such failure to fulfill role obligations, harm to others, or legal problems."

Symptoms of alcohol withdrawal in humans may include headaches, anxiety, insomnia, seizures, hallucinations and heart palpitations, among others, according to the American Addiction Centers.

"As far as we know the longer term effects of alcohol on dogs are similar to those for humans i.e. risk of dependency, liver damage, cardiovascular problems, elevated risk of cancer and neurological damage," Hamilton said.

Other animals have also been seen to get drunk from alcohol in the wild.

"It is widely accepted that other mammals and birds seek out fermented fruit or eat insects that contain mind-altering chemicals," Hamilton said.

However, many species have impressively high tolerances to alcohol: one study published in the journal Proceedings of the National Academy of Sciences in 2008 found that pen-tailed treeshrew of Malaysia feed on fermented nectar from the flower buds of the bertam palm plant, consuming many times the human limit, but don't seem to get drunk.

"There is more evidence of other animals developing alcohol addiction-like responses – particularly rats in lab studies," James Morris, a postdoctoral research fellow in alcohol-related issues at London South Bank University, told Newsweek. "Or more interestingly, places where monkeys steal drinks (e.g St Kitts) and some appear to show more disposition towards drunkenness."

Despite the antics of some wild animals, domestic pets don't seem to have a hankering for booze.

Although animals, including pets, may occasionally ingest alcohol drinks or food and industrial and medical products containing alcohol, in general they won't seek them out," Sumnall said. "In laboratory studies animals will only usually drink alcohol if they're trained to do so and often only when it's highly sweetened. Chronic exposure to alcohol outside of the laboratory is therefore usually a result of mistreatment by humans."

Luckily, alcohol dependence in dogs can be overcome, as shown by Coco, who is slowly getting better.

"Coco is doing very well indeed and well on his way to a full recovery," Helen Lecointe, the Woodside Animal Rescue Trust sanctuary manager, previously told Newsweek.

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