Does CBD Have Any Side Effects?

by Kat Austin September 28, 2020 7 min read

Does CBD Have Any Side Effects? - Vida Optima™

Various reports buzz about the potential benefits of CBD for conditions like anxiety, pain, and insomnia, but researchers agree that the evidence, while promising, is still widely inconclusive.

Fortunately, they also mostly agree that the non-psychoactive cannabinoid also boasts a stable safety profile, but even “safe” medications may come with risks.

So does CBD have any side effects?

Potentially, yes!

And although CBD side effects are frequently regarded as “rare” and “mild,” you still need to know the warning signs of adverse reactions and the steps you can take to avoid them before starting a CBD routine.

So what are the most common CBD side effects?

Let’s get started:

Table of Contents
Common CBD Side Effects
What Causes CBD Side Effects?
Who is at Risk?
How to Lower the Risk of Adverse Effects
What to Do if You Experience CBD Side Effects

Key Takeaways

  • Like all supplements and medications, CBD poses some level of risk for adverse reactions.
  • According to research, CBD side effects are rare and usually mild, and CBD is regarded as "generally safe" by experts and leading organizations.
  • Side effects may include tiredness, weight and appetite changes, headaches, or other mild discomforts, and usually go away after the CBD wears off.
  • Adverse reactions to CBD may actually be linked to improper dosing, fake or low-quality products, or drug interactions.
  • You can lower your risk of adverse reactions by choosing only high quality CBD products, starting with low doses, and including your doctor when building your CBD routine, especially when taking other medications.


Common CBD Side Effects

Nearly every medication, supplement, or wellness product comes with some level of risk, and CBD is no exception. Several studies have set out to evaluate this risk, and most have confirmed similar results.


A man measuring out the correct CBD dose.
One study recorded the adverse reactions of patients taking CBD (mostly for epilepsy or psychotic disorders) and suggested that the “favorable safety profile of CBD in humans was confirmed.” Here, the most common side effects reported were diarrhea, tiredness, and changes to weight or appetite.


Other sources suggest that daily doses in excess of 300mg have been safely tolerated. Other side effects may include dry mouth, low blood pressure, lightheadedness, and drowsiness.

Additionally, anecdotal reports frequently mention tiredness, headaches, or appetite changes as reactions to starting CBD.

Although there is currently very little evidence on the matter, some people also suggest that some side effects may have more to do with the CBD formula than the CBD molecule itself.

This theory suggests that Full Spectrum CBD (which includes trace amounts of THC) may incite anxiety in some people. This is led by limited evidence that THC (in high-THC cannabis) can incite anxiety and paranoia in some people.

Of course, THC levels in industrial hemp products must be less than 0.3% to comply with federal regulations, so many experts think that it’s unlikely that these low THC levels pose any added risks. Still, CBD Isolate and Broad Spectrum CBD are made to be THC-free to offer an alternative to people who may be sensitive to THC.

To recap, the usually rare, but potential side effects of CBD may include:

  • Tiredness
  • Appetite changes
  • Weight changes
  • Diarrhea
  • Dry mouth
  • Low blood pressure
  • Lightheadedness
  • Headaches
  • Anxiety (only for formulas with THC)

What Causes CBD Side Effects?

All in all, the side effect profile for CBD is mild and comparable to many “safe” over-the-counter medications. Although side effects are usually rare, anyone could potentially experience adverse reactions to CBD.

Keep in mind that CBD is thought to interact with the endocannabinoid system (a bodily system known for maintaining balance) so it’s possible that CBD could actually throw off the balance in perfectly healthy people, which may explain the anecdotal reports of headaches or other mild discomforts.

Of course, in today’s world (where we are surrounded by low-quality foods, poor quality air, and various synthetic chemicals), it may be safe to bet that most people are a little off-balance.

Still, for most people, there may be a reason for adverse reactions, which means that CBD side effects may be avoidable in some cases. Here are some risk factors for adverse reactions to CBD:

Improper Dosing

Many experts agree that improper dosing is likely an imposing factor behind many CBD reactions.

CBD is thought to have a biphasic effect, meaning that low doses and high doses may be entirely different. Alcohol is a good example of something with biphasic effects. In small amounts, alcohol may act as a stimulant. Larger doses may have the opposite effect, acting as a sort of sedative.

Similarly, large doses of CBD may cause tiredness, which can be labeled as an adverse reaction for people who aren’t using CBD for sleep. Actually, though, this “side effect” is actually just a mode of function, and smaller doses may help avoid the issue altogether.

The dosing issue may also be the reason that people report experiencing headaches and nausea with high doses, too.

Low Quality or Synthetic Products

Many adverse reactions to CBD that have been reported were caused by low-quality formulations. In fact, many CBD brands have been called out for using cheap ingredients and shortcuts, like synthetic cannabinoids, to save on costs.

These synthetic cannabinoids and poorly made formulas have resulted in unwanted psychoactive effects, and many brands have already been issued a warning by the FDA for false claims, inaccurate CBD levels, and more.

Still, it’s important to note that these adverse effects were generally in response to something other than CBD, like the addition of K2, a synthetic version of THC often sold as a recreational street drug.

Other Ingredients in CBD Products

Even when using a well-made CBD product sourced from high-quality hemp, it’s possible to experience adverse reactions to some of the ingredients used in the product instead of CBD itself.

For instance, MCT oil or other carrier oils may be linked to diarrhea in people who aren’t used to ingesting these oils. MCT oil from coconuts is an allergen that may not be suited for all people.

Alternatively, some CBD products may include other herbs and botanicals that cause adverse reactions. Essential oils are a common example of an ingredient used to enhance the CBD formula. While many essential oils are considered to be harmless when properly diluted, some people may have allergies or sensitivities to certain oils.

Some CBD products also use ingredients like honey or artificial sweeteners that may cause adverse reactions or allergic reactions in some people.

Some CBD vaporizers are known to have controversial ingredients that may cause adverse effects, like lightheadedness, or even allergic reactions.

Drug Interactions

Another reason to take precaution is when taking CBD alongside other medications.

According to many experts, CBD should come with a “grapefruit warning” similar to many medications. On typical prescription medications, this warning suggests not taking the medication with grapefruit juice because it utilizes the same liver pathways for absorption, which may decrease the body’s ability to absorb the drug.

Similarly, you may not be able to take CBD alongside other medications that utilize the cytochrome P450 pathways in the liver without decreasing the absorption.

In other words, CBD side effects as a result of drug interactions may not be “side effects” of CBD at all, rather the effects of your regular medication failing due to malabsorption. To be safe, always check with your doctor before adding CBD to your wellness routine.

Who is At Risk?

Although we currently believe CBD reactions to be rare, we still don’t have enough information to say which individuals may be at greater risk of adverse reactions.

However, due to ethical reasons and testing restrictions, there is currently no evidence regarding CBD safety for pregnant women or their developing baby. There is also only very limited evidence regarding CBD’s effect on children.

At this time, CBD is not recommended for women who are pregnant or breastfeeding. While CBD has shown promise treating certain conditions in children (and is even the main component of an FDA approved medication designed to treat childhood epilepsy), CBD should only be given to children under the guidance of a doctor.

How to Lower the Risk of Adverse Reactions

Although CBD’s side effects are still being studied, many researchers are confident that the risks associated with CBD are small. There are still a few steps you can take to lower the risk from the beginning of your CBD journey:

  • Consider small doses. Learning how to dose CBD can be confusing, and there are no hard and fast rules for where to start. Try starting with a small dose (10mg or less) and increasing the dose slowly, waiting a few days in between to monitor your experience. If you start to experience adverse effects after increasing your dose, that may be a sign that you’re taking too much.
  • Track your experience. Keeping track of how much CBD you take, how you feel, and all good and bad reactions can help you pinpoint where you may have gone wrong after an adverse reaction. It also can help your doctor see how you are using CBD so he or she can give better guidance.
  • Take CBD separately from other medications. Because CBD may interact with other medications, you may not want to take the two at the same time. If you get the go ahead from your doctor to take CBD while taking other prescriptions, you still may want to take CBD a few hours before or after other medications.
  • What to Do if You Experience CBD Side Effects

    If you experience adverse reactions to CBD, don’t panic! Most reactions are mild and will pass after a few hours.

    Of course, if you experience reactions that are severe or that impair your ability to function properly, you should contact your doctor and/or emergency services. Severe reactions have not been linked to CBD, but they may be caused by some synthetic cannabinoids.

    After experiencing a mild reaction to CBD, you should discuss it with your doctor. In many cases, you may be able to resume your CBD routine at a lower dose with no side effects.


    1. “An Update on Safety and Side Effects of Cannabidiol: A Review of Clinical Data and Relevant Animal Studies”
    2. “‘Russian roulette’: Investigation finds CBD products spiked with illegal synthetic marijuana”
    3. “Warning Letters and Test Results for Cannabidiol-Related Products”

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