Does CBD Have Side Effects?

CBD has become increasingly popular as a natural supplement, and it doesn’t look like its popularity is going away anytime soon.

But even with all of the talk of CBD, it is still an enigma to many people. They hear of it, but not a whole lot of details about what it actually is or does. And one of the first questions that comes into people’s minds as they start to learn more about CBD is, “Does CBD oil have side effects?”

What’s the Deal with CBD Oil Anyway?

When someone takes CBD, there is a biochemical process that takes place in the body, and more specifically with the body’s endocannabinoid system. CBD interacts with the CB1 and CB2 receptors within our body and is able to interact with the brain and nervous system without creating any psychoactive effects.

Our endocannabinoid system (ECS) is crucial to our body’s well-being. Only having been discovered within the last 50 years, we have found that the ECS helps regulate the body’s homeostasis and balance. It does this through managing different body systems like appetite, sleep, mood, immune response, and pain management.

There are constant triggers in the modern world that take our body out of balance. When CBD interacts with the receptors in the ECS, it helps assist with the regulation of these different bodily processes.

CBD has been shown through research to help assist in difficulties with different functions like irregular or interrupted sleep patterns, stress, anxiety, chronic pain, and other similar conditions. But with the undeniably promising research and personal accounts of many, those folks who haven’t tried taking CBD for themselves wonder if the claims made about CBD are legitimate or too good to be true.

Furthermore, because we are constantly hit with a barrage of advertisements for approved prescription medicines that feature a laundry list of negative side effects, wondering about the side effects of supplement like CBD is perfectly normal. Actually, we think it’s very smart!

Does CBD Oil Have Side Effects?

There are many small-scale studies out there that have looked at the effect of CBD on adult humans and have found that there are no long-term, lasting side effects.1

Research has not found any significant side effects from CBD on the central nervous system2, vital signs, or mood, even among people who take high doses of CBD.3

But while there aren’t any long-term negative side effects, there are the occasional cases of potential, mild and temporary side effects. These however are few and far between. The number of people that have reported experiencing these side effects are far outweighed by those people who experience no side effects whatsoever.

Reported CBD Side Effects:

  • TirednessCBD has a different effect on everyone, especially depending on the serving size. When taking a low to moderate serving of CBD, some people experience higher levels of energy and a generally uplifted demeanor. While when taking higher servings of CBD, individuals sometimes become tired or drowsy.4 If CBD affects you in this way, and you’re not using it for better sleep, this could be a sign that you need to decrease your dosage.
  • Slight Drop in Blood Pressure — Some studies have shown that higher doses of CBD can cause a slight drop in blood pressure.5 Yet, at the same time numerous studies have shown no effect of CBD on blood pressure.67 While this may not be an issue for a lot of people, it can be a pretty big deal for someone taking medication to lower their blood pressure or it they already have low blood pressure. If you do have low blood pressure, talk to your doctor before taking any CBD products.
  • Lightheadedness — Lightheadedness8 is one of the more mild and temporary side effects that can be experienced taking CBD. Also be aware, though, that lightheadedness could also be a sign of low blood pressure. Just something to keep in mind.
  • Dry Mouth — Sometimes dry mouth can occur because the ECS’s inhibition of salivary secretion.9 This could be a result of CBD getting involved with this system’s processes. Not to worry, though. This side effects is easily managed by making sure to drink a lot of hydrating fluids before, after and during your CBD consumption. This will ensure that your body stays hydrated throughout the day and will help your ECS continue to work smoothly with the CBD.
  • Irritability — Many people take CBD as a means to counteract stress, which can lower a person’s feelings of irritability. Yet survey studies have indicated rare occurrences of irritability as a side effect of CBD.10 For those that deal with irritability as a side effect, it could be stemming from a neurochemical incompatibility with CBD. Everyone is wired differently, and some people’s preexisting neurochemistry doesn’t respond well to how CBD interacts with the body. This can cause a side effect of irritability.
  • Loss of Appetite — While THC is widely known for causing an increase in appetite, CBD doesn’t have the same effect. In fact, the research suggests that CBD may reduce or suppresses appetite in both humans and animals.11 So if you are taking CBD, you might notice that you aren’t hungry as often and could potentially end up losing some weight since you aren’t eating as much.
  • Diarrhea — When testing CBD in patients that suffered from epilepsy or psychotic disorders, one of the most common side effects was diarrhea.12 The exact cause of this side effect isn’t fully understood. If you do experience diarrhea as a CBD side effect, talk to your doctor.

CBD liver health - CBD drug interactions

Dealing With CBD Side Effects

Even with this list of minor and short-term side effects, most people do not experience them. Studies have shown results that are highly supportive of CBD’s potential, safety and viability, even in higher doses.

If you are worried about experiencing side effects while taking CBD, make sure that you start out with a smaller dose and slowly increase your dosage until you get the desired effects. With CBD, it’s best to use the smallest dose that works for you. A smaller dose means that you will have a lower chance of dealing with any mild side effects.

Oftentimes people find that they are experiencing side effects because their daily serving is too high. Dropping down the amount of CBD you are taking is another way that you could see side effects disappear.

Making sure you have quality CBD oil is also important. Low-quality CBD could cause more side effects than high-quality, full or broad spectrum CBD.

If you are taking any prescription medications, it’s important to talk to your doctor about any potential drug interactions between CBD and your medications. Similar to grapefruit, CBD can affect the liver’s ability to process certain pharmaceutical drugs.13 CBD can make the liver less effective at processing some medications. Please make sure you talk to your doctor before taking CBD if you are also taking other medication.


Although CBD may not be right for everyone, if you do deal with a physical or mental ailment that can be benefitted by CBD, it’s a good natural option to try.

It’s no wonder that so many people are opting for relief through CBD for many different health issues. It’s an alternative and natural option with low potential for side effects.

I’d say that’s a win for CBD.

  1. Iffland, Kerstin, and Franjo Grotenhermen. “An update on safety and side effects of cannabidiol: a review of clinical data and relevant animal studies.” Cannabis and cannabinoid research 2.1 (2017): 139-154.
  2. Scuderi, Caterina, et al. “Cannabidiol in medicine: a review of its therapeutic potential in CNS disorders.” Phytotherapy Research: An International Journal Devoted to Pharmacological and Toxicological Evaluation of Natural Product Derivatives 23.5 (2009): 597-602.
  3. Machado Bergamaschi, Mateus, et al. “Safety and side effects of cannabidiol, a Cannabis sativa constituent.” Current drug safety 6.4 (2011): 237-249.
  4. Porter, Brenda E., and Catherine Jacobson. “Report of a parent survey of cannabidiol-enriched cannabis use in pediatric treatment-resistant epilepsy.” Epilepsy & Behavior29.3 (2013): 574-577.
  5. Stanley, Christopher P., William H. Hind, and Saoirse E. O’sullivan. “Is the cardiovascular system a therapeutic target for cannabidiol?.” British journal of clinical pharmacology 75.2 (2013): 313-322.
  6. Resstel LB, Tavares RF, Lisboa SF, Joca SR, Correa FM, Guimaraes FS. 5-HT1A receptors are involved in the cannabidiol-induced attenuation of behavioural and cardiovascular responses to acute restraint stress in rats. Br J Pharmacol 2009; 156: 181–8.
  7. Resstel LB, Joca SR, Moreira FA, Correa FM, Guimaraes FS. Effects of cannabidiol and diazepam on behavioral and cardiovascular responses induced by contextual conditioned fear in rats. Behav Brain Res 2006; 172: 294–8.
  8. Consroe, Paul, Reuven Sandyk, and Stuart R. Snider. “Open label evaluation of cannabidiol in dystonic movement disorders.” International Journal of Neuroscience 30.4 (1986): 277-282.
  9. McConnell, W. R., et al. “A study of the effect of delta 9-tetrahydrocannabinol (delta 9-THC) on mammalian salivary flow.” Journal of Pharmacology and Experimental Therapeutics 206.3 (1978): 567-573.
  10. Hess, Evan J., et al. “Cannabidiol as a new treatment for drug‐resistant epilepsy in tuberous sclerosis complex.” Epilepsia57.10 (2016): 1617-1624.
  11. Wiley, Jenny L., et al. “CB1 cannabinoid receptor‐mediated modulation of food intake in mice.” British journal of pharmacology 145.3 (2005): 293-300.
  12. Szaflarski, Jerzy P., et al. “Long‐term safety and treatment effects of cannabidiol in children and adults with treatment‐resistant epilepsies: Expanded access program results.” Epilepsia 59.8 (2018): 1540-1548.
  13. Bornheim, Lester M., and Maria Almira Correia. “Selective inactivation of mouse liver cytochrome P-450IIIA by cannabidiol.” Molecular pharmacology 38.3 (1990): 319-326.