Carnitine for Dogs

If you’re interested in health and fitness, you may have heard of carnitine. Its main function is to convert fat into energy. Although more research is needed, it’s been popular for years among humans as a fat burner and to enhance athletic performance. 

Carnitine (also known as levocarnitine or L-carnitine) is an amino acid nutrient. It occurs in two forms, known as D and L, but only L-carnitine is active in the body and is the form found in food. D-Carnitine doesn’t provide the same benefits, but don’t worry about mixing them up as it shouldn't even be available as a supplement in the US. Carnitine’s name comes from the Latin word carnus (or flesh) because the compound was first extracted from meat. 

Although the jury's out on whether carnitine actually helps with weight loss, it is what’s considered a conditionally essential nutrient in humans and dogs. This means that your dog’s body should produce enough on its own as long as they have a high-quality diet. A vegan diet, heart problems, or certain genetic issues can cause a carnitine deficiency. 

So, what exactly is carnitine? And how can you tell if your dog might benefit from a supplement? Let’s dig a little deeper! 

Carnitine supports a number of important functions in your dog’s body, including heart, brain, and muscle function. This essential amino acid plays a key role in producing energy. Dogs produce L-carnitine using lysine and methionine found in the liver, brain, and kidneys. It attaches itself to long-chain fatty acids and shuttles them to the mitochondria of the cell. This is where it’s converted into ATP – the body’s chemical energy source.

Carnitine is sometimes recommended as a supplement for dogs suffering from heart issues. According to one study, some breeds of dogs have shown dramatic improvement in heart function after supplementation with carnitine and taurine. It’s often used along with other medications to treat dilated cardiomyopathy (DCM), a type of heart disease in dogs. DCM is prevalent in several dog breeds, including Cocker Spaniels, Boxers, Great Danes, and Dobermans. It has also been used for other heart diseases and for valproic acid toxicity. Although carnitine will not cure heart disease, it’s sometimes used alongside prescription medication because of its ability to increase blood flow and metabolize fats.

If your dog eats a high-quality dog food and is in good health, their body should be producing its own carnitine. Because of this, there is no minimum daily recommended intake of carnitine for dogs. 

If your vet has prescribed carnitine along with medication to help treat heart disease, they commonly recommend a dose of 50-200 mg of carnitine per kg of your dog’s body weight, taken orally three times a day. This can vary based on your dog's age, breed, or condition. 

If your considering adding carnitine into your dog's food because they’re on a restricted, vegan or vegetarian diet, one suggestion is to mix 35mg/kg body weight daily into moist food. 

Animal products like meat, fish, poultry and milk are the best sources of carnitine, but you can find a few non-animal sources. In general, the redder the meat, the higher its carnitine content. Interestingly, according to this review, food sources of L-carnitine have a greater absorption rate than supplements.

Foods high in carnitine include:

• Beef steak
• Pork
• Milk
• Fish
• Chicken breast
• Cheddar cheese
• Whole wheat bread
• Asparagus

There aren’t any known symptoms directly related to carnitine deficiency, but it can cause a variety of health problems for dogs. Most significantly, it’s usually associated with heart disease (cardiomyopathy). In the case of heart failure, it can be difficult to determine if carnitine deficiency is what lead to it or occurred as a result of it. True carnitine deficiency is likely a result of genetic abnormalities in carnitine production or absorption. 

If you see any of these signs of heart failure, it calls for a visit to the vet:

• Abnormal heart rhythm
• Tiredness
• Reduced ability to exercise
• Poor appetite
• Shortness of breath
• Panting or coughing
• Greyish mucus membranes in the mouth
• Enlarged abdomen

Treatment of carnitine deficiency

A definitive diagnosis of carnitine deficiency is rare, but the recommended treatment would be a supplement containing L-carnitine. Your vet would determine the proper dosage based on the size of your dog. Because L-carnitine is quite harmless, it's often prescribed for dogs with heart failure whether the known cause is carnitine deficiency or not. It's usually combined with a taurine supplement because these two amino acids work together to transport necessary fats throughout the body and help cells metabolize nutrients.

Since dogs produce L-carnitine naturally and excrete any excess, there’s generally no need to worry about giving your dog too much. An overdose usually doesn’t produce any harmful effects. If your dog had a large overdose, call your vet, the Pet Poison Helpline, or the ASPCA Animal Poison Control Center for advice. 

Your pup can experience some unpleasant side effects from a large dose of the supplement, including digestive problems like nausea, loss of appetite, and diarrhea. You can try giving the supplement with food to minimize any stomach issues. 

A healthy, protein-rich diet should be all your dog needs to produce the right amount of carnitine it needs to stay healthy. Some pet parents give their dogs an L-carnitine supplement to control their weight and support muscle repair, but whether it's effective or not is disputed. If your dog has a heart condition or a genetic predisposition to carnitine deficiency, your vet may recommend a supplement to give them a helping paw. 

The supplement is given by mouth in the form of a capsule, tablet, liquid, or powder. If you’re giving it to your dog in powder form, try mixing it into some wet food. The effects on your canine's cardiac health might not be visibly obvious without laboratory results, and it can take a few weeks before the full effects kick in. Gradual improvements could be apparent after a few days.

Keep in mind that certain supplements and medications can interact with each other and you would need to discuss this with your vet. For example, valproic acid used to support dogs with seizures, can potentially interact with L-carnitine so it’s worth avoiding this combination. Like with all supplements and medications, you should consult your veterinarian before adding them to your dog's diet. 

As you can see, carnitine serves a crucial role in the canine body. Deficiencies are unlikely because dogs create carnitine in their own bodies, but they can still happen if a dog eats an unbalanced diet or has an underlying condition.