Question: CBD can make me feel tired or drowsy. What is that all about?
Bonni Goldstein: CBD has biphasic
properties, which means that low doses give a completely opposite effect to higher doses. It appears that low doses of CBD are stimulating or alerting; lower doses, such as 10 - 25 milligrams of CBD, should not put you to sleep and should be okay to take during the daytime without feeling like you have to take a nap.
Higher doses of CBD cause sedation. I see it in pediatric patients with epilepsy or autism, or elderly patients who are using it for dementia or chronic pain. If you give them too much, they fall asleep. People are asking where the limit is, but everybody is a little different. I’d say 50-100 milligrams should not make you too tired but it might. But I have pediatric patients taking 400 milligrams or more per day going to school fully functioning. Remember that the underlying chemistry of your brain matters in the way you respond to cannabis.
Is it possible to take too much CBD? What would be the implications of that?
There is no real danger of overdosing with CBD. [When the FDA studied the safety of the CBD-isolate Epidiolex
], people were given as high as 50 milligram per kilogram of body weight per day and it was well tolerated. [The FDA recommends a 20 mg/kg maintenance dosage of Epidiolex. For a person weighing 60 kilograms or 132 pounds that would be 1,200 mg/day.]
If you take a large dose of CBD, you likely will be sedated, but again, it’s not dangerous. If you take too much Aspirin or Tylenol, you can really harm your organs. People die from Tylenol overdoses
. Another side effect with large doses of CBD is gastrointestinal upset (bloating, diarrhea, stomachache).
How do you know you’ve taken too much?
Listen to your body. For instance, if you feel sedated when you don’t want to be, or if you have gastrointestinal upset, you would likely want to adjust your dose. Sometimes parents of my pediatric patients report that the children have a tummy ache, bloating, diarrhea. That means that their body has hit that point where they may be taking too much. It could be due to the specific CBD preparations, so look at the ingredients to make sure there are not a lot of other ingredients in the bottle, and then adjust dosing, timing or product.
What about interactions with other drugs? Is there a reason not to take CBD at all?
CBD is metabolized in the liver in the same enzyme system as about 60-70% of pharmaceuticals. Let’s say you take a medicine called valproic acid, a fairly common seizure medication. CBD and this drug compete for the same enzymes. If valproic acid is affecting the CBD level, no big deal, because CBD is not going to harm you. But we know too much valproic acid
can be a problem.
You have to be careful. There are other drugs as well that CBD can interfere with, for example blood thinners. And remember CBD has not been tested with every other drug. If you have help with a healthcare professional or a pharmacist who is knowledgeable about drugs in general and also about cannabis, they can look at your list of drugs and how they’re metabolized. They can see if there’s overlap with CBD.
There is no absolute reason that somebody could not take CBD. But I might suggest against it and I have done so for patients who take life-saving medications that might interact with CBD. I don’t want to mess with those drugs and might recommend a different cannabinoid.
Is it possible to feel nothing when taking CBD? And does CBD cause tolerance? This is what we’ll discuss in part three of the Q&A with Bonni Goldstein. If you’d like to share your thoughts on today’s edition, please send them my way