Whether garlic powder is bad for dogs is something may dog owners may wonder about considering that nowadays, there is a lot of interest in cooking home-made meals for dogs which may require this ingredient. Sometimes, garlic powder may also be found in the ingredient list of some dogs treats, leaving dog owners baffled since garlic and onion are known for having the potential for being toxic to dogs. So is onion powder really bad for dogs or does it all boil down to the amounts used? Veterinarian Dr. Ivana Crnec provides clarifications about the use of garlic powder in foods consumed by dogs.
Is Garlic Powder Bad For Dogs?
When it comes to dogs, garlic is a rather controversial topic. In the past it was believed that all members of the Allium family (garlic, onion, leek and chives) are toxic for dogs. If eaten in smaller amounts they would cause gastrointestinal upset (manifested with vomiting and diarrhea) and if consumed in larger amounts they would cause anemia.
Nowadays, recent studies suggest that if consumed in proper amounts, garlic can be beneficial. To better understand this subject of controversy, it helps taking a look at the pros and cons of garlic use in dogs.
Cons of Garlic
The toxic effect of garlic on dogs is due to the presence of a substance called N-propyl disulfide. This toxic substance causes oxidative damage to the dog's red blood cells or better said their oxygen carrying compound – hemoglobin. Once damaged, the red blood cells become very fragile, burst and are removed from circulation. Due to its origin, this type of anemia in dogs is classified as hemolytic and is known as Heinz anemia.
Dogs with garlic intoxication will show the following signs and symptoms:
- Abdominal pain
- Vomiting and diarrhea
- Excessive drooling
- Bad breath
- Blood in the urine
- Elevated heart and breathing rate
- Exercise intolerance
- Jaundice (yellow skin and eyes)
In cases of gastrointestinal upset, the affected dog will show the following signs and symptoms:
- Profuse diarrhea
- Loss of appetite
- Abdominal pain
Certain dog breeds (Akita, Shiba Inu, Japanese Spitz) are at higher risk of developing Heinz anemia if fed garlic. This may be due to the fact that these breeds naturally have higher red blood cells counts. Additionally, it is postulated that powdered garlic is more toxic than fresh garlic.
The Pros of Using Garlic
If properly used, garlic can have several health benefits:
It boosts the immune system – garlic promotes increased activity of the killer cells (cells responsible for destroying microbes and cancer cells). Therefore, garlic is recommended for dogs with suppressed immune systems and with cancers.
It fights infections – garlic is good for combating bacterial, viral, fungal, parasitic and protozoan infections. If crushed and diluted in olive oil, garlic can be used as a topical antiseptic.
It enhances the liver function – garlic has detoxifying effects that help the liver get rid of toxins and harmful substances.
It lowers the blood cholesterol and triglyceride levels – dog breeds (Schnauzers and Beagles) predisposed to hyperlipidemia (high levels of fats in the blood) should be fed uncooked garlic.
It acts like cardiovascular tonic – garlic inhibits the formation of blood clots. Since it reduces the levels of cholesterol and triglycerides in the blood it also reduces the risk of atherosclerosis thus acting like the perfect cardiovascular tonic.
It repels ticks and fleas – the exact mechanism of action is not determined. However, it is believed that the process of metabolizing garlic is followed by formation of odors that are released from the body’s pores. Those odors have the power to repel external parasites such as ticks and fleas.
Quantity and Frequency
Both the garlic’s benefits and toxic effects depend on two important factors – quantity and frequency. Occasional uses of moderate amounts can be beneficial. On the flip side, eating too much garlic, too often is toxic.
It takes between 15 and 30 grams of garlic per kilogram of body weight for the toxic effects to kick in. The average clove of garlic weights between 3 and 7 grams, so, a dog would need to eat a lot of garlic before it starts feeling sick.
According to several authors, dogs can safely eat around 1/8 tablespoon of powdered garlic per pound of food. This dose can be safely repeated 3 to 4 times a week. The safe amount of fresh garlic for dogs depends on their size:
- Dogs weighing 10-15 pounds can eat half a glove
- Dogs weighing 20-40 pounds can eat 1 clove
- Dogs weighing 45-70 pounds can eat 2 cloves
- Dogs weighing 75-90 pounds can eat 2 and a half cloves
- Dogs weighing over 100 pounds can eat 3 cloves.
Dog nutritionists recommend using 1 clove of fresh garlic per 10-30 pounds of body weight per day. This amount is good for boosting the immune system and preventing cancer. However, it is also recommended to practice off-garlic periods (at least 1-2 days per week).
Although for most dogs moderate amounts of garlic are safe, there are certain circumstances in which garlic is forbidden. Garlic must not be fed to dogs suffering from:
- Anemia – dogs with pre-existing anemia are at higher risk of developing garlic-related issues. Additionally, garlic is forbidden for dogs scheduled for surgery.
- Lupus – garlic is forbidden for dogs with lupus or other autoimmune conditions. This is because garlic stimulates the immune system and these conditions already make the immune system over-active.
Garlic is also not recommended for puppies younger than 6 to 8 weeks. That is due to the fact that puppies do not start producing new red blood cells until at least 6 to 8 weeks old.
Garlic, together with onion, leek and chives are all members of the Allium family. Containing N-propyl disulfide, all members of this family are toxic for dogs. If consumed in substantial amounts or too frequently, the N-propyl disulfide damages the hemoglobin. As a result to the damage, the red blood cells rupture and are removed from circulation. This leads to a severe condition known as hemolytic anemia. Even if the amount of ingested garlic is big, but not enough to cause toxicity, it will probably provoke gastrointestinal irritation.
In recent years, the popularity of garlic supplementation for dogs has risen. Many non-conventional dog nutritionists promote the garlic’s health benefits. According to them, it all depends on how much and how often dogs would eat garlic. Additionally, it is postulated that if properly prepared, the toxic substance in the garlic can be deactivated thus making it perfectly safe for use. However, the scientific data that support this movement are still not sufficient, and until future changes and discoveries, the use of garlic in dogs remains controversial.
- The Complete Herbal Book for the Dog and Cat, by Juliette de Bairacli Levy
- Innovative Veterinary Care Journal, Garlic – well-rounded and safe for your practice!
About the Author
Dr. Ivana Crnec is a graduate of the University Sv. Kliment Ohridski’s Faculty of Veterinary Medicine in Bitola, Republic of Macedonia.