In recent years, many Americans have turned to cannabidiol (CBD) as a wellness tool. Yet there’s some concern and confusion about the possible risks and benefits of taking CBD. In this article, we’ll cover how CBD affects three important organs: your liver, heart, and kidneys.
How does CBD affect the body?
CBD affects the body and one’s health by interacting with your endocannabinoid system (ECS). The ECS impacts many bodily functions, such as pain levels, mood, and the action of your immune system.
CBD has several potential health benefits, including:
Pain relief
Support for anxiety and depression
Helping with substance use disorders
Better sleep
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Epidiolex (cannabidiol) is an FDA-approved form of CBD oil. It’s used to treat certain childhood forms of epilepsy.
Can CBD harm your liver or kidneys?
CBD doesn’t appear to harm your kidneys. But it may raise the risk of liver damage in certain cases.
CBD and the liver
The FDA warns that CBD can cause liver damage. In clinical studies for Epidiolex, high levels of liver enzymes were a main reason treatment had to be stopped. This is because high liver enzyme levels can be a sign of liver damage.
These high liver enzymes were more likely at higher doses of the medication. And they were also more likely to happen when people were taking certain other seizure medications with Epidiolex (like valproic acid).
But Epidiolex doses are much higher than you’ll find in most over-the-counter (OTC) CBD products. And other studies suggest that CBD might actually be helpful for the liver after surgery. So, there’s still more research to be done in order to know for sure exactly how CBD affects the liver.
CBD and the kidneys
There’s currently no evidence that CBD is harmful to your kidneys. CBD might even be able to prevent kidney damage in certain situations.
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Is CBD safe to take?
In general, CBD seems to have few side effects. They aren’t common, but reported side effects include:
Diarrhea
Nausea or vomiting
Fatigue
Drowsiness
CBD products that are OTC aren’t regulated by the FDA. This means they don’t have to be tested for safety. It also means they may contain more or less CBD than the label states — or that they may have other ingredients that aren’t even listed (such as pesticides).
Buying only high-quality CBD products helps you avoid toxic chemicals. High-quality products are always tested by third-party labs for safety and purity. These lab results should be available from the manufacturer. State-regulated cannabis dispensaries are another good place to buy CBD. These stores usually have strict rules for testing and labeling.
Is CBD bad for your heart?
There’s no evidence that CBD is bad for your heart.
CBD’s effects on the heart are not the same as other chemicals found in the cannabis plant. For example, tetrahydrocannabinol (THC), the main mind-altering chemical in cannabis, may be harmful to the heart. A 2024 study showed an increased risk of heart disease, heart attack, and stroke associated with consuming cannabis. The risk is highest for those who consume cannabis daily.
But CBD has powerful anti-inflammatory effects. And because of this, heart and lung experts think that CBD could actually help protect your heart in certain instances.
Experts also think that CBD could have benefits for people with high blood pressure. But there aren’t enough human studies to confirm these promising ideas.
How much CBD is too much?
There aren’t clear medical guidelines about how much CBD people should take when using OTC products. When taking Epidiolex, your care team will use your body weight to figure out the safest dose for you.
Controlled research studies have tested a wide range of CBD doses. This includes doses ranging from 150 mg to 1,000 mg per day. Generally, unpleasant side effects (diarrhea or sleepiness) are more common at higher doses. Serious side effects from CBD alone are unlikely. But they can happen if CBD is taken along with THC or medications such as opioids or benzodiazepines. It’s unclear if CBD is the cause of the toxicity in these cases.
Experts recommend starting with a low dose of CBD and slowly raising it over time until you reach the desired effect. If you start to experience negative side effects, lower your dose and let your healthcare professional know.
It’s best to talk to your healthcare professional first before taking CBD with any other medications. There are drug interactions your care team will want to check for to make sure it’s safe for you. It’s also best to avoid alcohol while you’re taking CBD.
The bottom line
CBD (cannabidiol) is generally considered safe. But it may raise your levels of liver enzymes, which could be a sign of liver damage. In most cases, this happens with very high doses of CBD or when it’s taken with certain medications. CBD alone doesn’t seem to have a harmful effect on other major organs, like the kidneys or the heart. But keep in mind that this doesn’t apply to other cannabis products, which can be harmful to your heart.
Research is ongoing to understand how CBD affects the body. Talk to your healthcare professional before taking CBD products. They can help make sure it’s safe for you.
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References
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