Is CBD Oil Causing Diarrhea for Your Pet?

CBD is everywhere and many humans are finding it is making a huge difference in the lives of their dogs. And while cannabinoids are generally quite safe, as with any supplement or medication, there can be undesired results.

This week, we’re going to look at how to mitigate one of the most common undesired effects from CBD oil. When clients report their dog is experiencing diarrhea, gas or other GI distress after using CBD oil, we ask these four questions:

  1. What is the carrier oil or other ingredients in the CBD oil?
  2. Is the product made from organically sourced hemp -and- organic oil?
  3. How much CBD oil was given?
  4. What other medications or foods were given with the CBD oil?

What is in the CBD Oil?

The number one cause of diarrhea or GI distress with CBD oil is the type of oil. Olive oil, coconut oil, MCT or hemp seed oil are the usual carriers we see manufactures using in their formulations. If your dog is having an adverse reaction to an olive oil carrier, try switching to a formulation with coconut oil or MCT oil.

Another key factor can be additional ingredients. I’m a big believer in picking CBD oils with just two ingredients, the carrier oil and the cannabis or hemp oil. Other ingredients can not only interfere with the CBD action, but cause undesired results.

Organic Matters

In my 12 years of doing this, I have found that many of the top undesired effects stem from products made from hemp or cannabis that was not organically grown. Because the hemp industry is largely unregulated, the ONLY way to know if the product you select is organic is to ask for the certificate of analysis and then review it for pesticide residuals. I always look for ND which means None Detected when I review these tests. If your CBD product manufacturer will not provide this document, I recommend going with one that will.

How Much Did You Give?

Too much oil can result in GI distress. I always suggest to my clients that if they have to give 0.5mL (half a dropper full) or more per dose, then they should consider a CBD oil with a higher concentration of CBD in the bottle to minimize the amount of oil they need to give with each dose.

For example, if a 1 oz (30mL) bottle of CBD oil contains 300mg of CBD, then each full dropper or 1mL = 10mg CBD. If your dog needs half the dropper to get relief, then you are giving 5mg CBD. If you have a product with 1,000mg of CBD, then each full dropper or 1mL = 50mg CBD and to get the same 5mg CBD, you would only have to give 0.1mL or 1/10 of the dropper vs. 1/2.

Other Interactions

Unfortunately, what we don’t know about interactions with CBD outweighs what we do know. But we are learning all the time and with so many humans utilizing the value of CBD for their dogs, we are all learning from each other.

Best practices suggest separating prescribed medications from CBD by at least 2-3 hours to mitigate any undesired results or contraindications (especially with life sustaining medications).

Were any new foods or supplements introduced with the CBD oil? If you are trying other new medications or supplements at the same time, it is always recommended to introduce one product at a time, assess how each affects your dog, then combine if necessary or safe. This will allow you to better determine what may be the source of the undesired effect. If it’s your first time trying a CBD oil on your dog, give the first couple of doses when at home so you can observe how it is affecting your dog.


  • Choose a CBD oil that only contains two ingredients.
  • You might have to experiment to find an oil that best agrees with your dog.
  • Always select CBD oil from organically grown hemp or cannabis.
  • Ask for the Certificate of Analysis (COA).
  • Separate when you give the CBD oil from other prescribed medications.
  • If your dog experiences undesired effects, decrease the amount of CBD oil you are giving or switch to a brand with a different carrier.

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