CBD Oil Side Effects: Common and Severe

Sophia Delphi May 12, 2022 - 12 min read
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Hand holding CBD oil Bottle and Hemp besides it

Cannabidiol (CBD) is one of 115 cannabinoids found in the cannabis plant. Unlike tetrahydrocannabinol (THC), CBD does not make you high.

CBD oil is derived from hemp plants’ flowers and leaves. CBD products come in many different forms, including tinctures, edibles, and topicals.

CBD oil is growing in popularity as a natural way to relieve pain, anxiety, and other health conditions. But is CBD oil safe? And what are the potential side effects of CBD oil?

CBD Product Types and Their Potential Side Effects

When studies showed that CBD is non-toxic and non-addictive, it gained more popularity as a health supplement. Approximately one in seven American adults uses CBD for symptom relief as well as health maintenance, according to a Gallup survey from 2019.

Let’s look at different CBD products and their potential side effects first, before discussing CBD oil side effects in detail.

Sublingual (CBD Oil)

CBD oils and CBD tinctures are included in this group. Sublingual drops are placed under the tongue and held for a few minutes. Through this method, the CBD is directly absorbed into the bloodstream through capillaries under the tongue.

Side effects associated with this type of application include reduced appetite, dry mouth, and bowel changes.

Edibles (CBD Gummies and CBD Capsules)

The possible side effects of CBD edibles are the same as those of any other CBD product. These side effects can include mild dizziness, dry mouth, and lightheadedness.

However, CBD is not known to cause any severe side effects, and it’s considered to be generally safe.

Inhalation (Hemp Flowers and Vapes)

There are CBD products that you can consume by inhaling them, such as smokable CBD flowers and vape oil.

This type of CBD product can cause lung irritation since you’ll be inhaling smoke or vapor, especially if it contains solvents or additives. It can also cause dry mouth, dizziness, and lightheadedness. There have been reports of headaches as well.

However, CBD vaping is known to be safer than smoking cigarettes since it doesn’t produce the harmful by-products that smoking cigarettes do.

In many cases, CBD vaping may also have fewer side effects than other CBD products since it’s absorbed into the bloodstream more quickly than other forms of CBD.

CBD Topicals (Balms, Creams, and Salves)

There is limited research on the potential side effects of CBD topicals. It can happen to people allergic to hemp or marijuana, but it’s incredibly uncommon.

A small percentage of people may experience temporary redness, dryness, skin rash, hives, or itchiness.

As with any new product, it is always best to consult a physician before using CBD topicals.

The Common Side Effects of CBD

In general, CBD is considered to be safe. It’s well-tolerated by users and it doesn’t alter their physiology in a negative way, such as the blood pressure, heart rate, and respiratory rate.

Additionally, the fact that there are few cannabinoid receptors in the lower brainstem (part of the brain that controls heart and lung function) ensures CBD doesn’t lead to overdose.

However, this doesn’t mean that CBD is entirely free of side effects. These are the most common ones to be aware of:

Short-Term Side Effects of CBD

Feeling Drowsy

In most cases, sleepiness occurs with CBD dosages that are excessively high.

Naturally, high CBD doses promote sleep, while low CBD doses promote alertness and wakefulness.

This is a common side effect and usually goes away after a while. If you’re feeling drowsy, it’s best to avoid driving, operating heavy machinery, or any other potentially hazardous activity.

Lowered Blood Pressure

There is a temporary drop in blood pressure caused by CBD’s vasodilation effects on the blood vessels.

When blood flows freely through the blood vessels, there is less pressure against the walls of the blood vessels, resulting in reduced blood pressure.

Feeling Dizzy and Lightheaded

After consuming CBD, the drop in blood pressure may cause dizziness and lightheadedness, but this will subside as soon as the blood pressure returns to normal.

However, if symptoms persist or worsen despite using CBD for quite some time, it’s best to stop using it temporarily and consult your doctor before resuming.


Vomiting is a very rare side effect of CBD oil, but it might occur when you take CBD in large doses. It’s typically accompanied by nausea.

If you’re one of the few people who experience vomiting as a side effect of CBD oil, you can do a few things to help minimize the chances of it happening again.

First, start with a lower dose and work your way up slowly. You should also make sure that you’re taking your CBD oil with food and drinking plenty of water.

If you still experience vomiting after trying these tips, check the purity of your product first. You can do this by reading its certificate of analysis. If you can’t find the certificate, change your supplier to a more transparent one.

Changing Bowel Habits

Because CBD relaxes the bowels, some people who take it develop mild diarrhea as a side effect. However, it’s also possible that the changes in bowel habits are linked to the other ingredients found in CBD oil, such as the carrier oil in which the CBD is suspended.

Dry Mouth

Research has shown that cannabinoids can reduce saliva production, causing cottonmouth (dry mouth or xerostomia).

Fortunately, simply drinking plenty of water helps alleviate dry mouth.

Drug Interactions

There are a few potential drug interactions to be aware of when taking CBD. For example, CBD can increase the sedative effects of medications like benzodiazepines and barbiturates. It can also elevate the levels of other substances in the blood, such as anti-seizure tablets.

Therefore, it’s critical to speak to your doctor before taking CBD if you’re taking any other prescriptions. Depending on your medication and health, your doctor may need to adjust your drug regimen or recommend delaying CBD use.

CBD’s Long-Term Side Effects

Research on long-term CBD use is still limited, but a study of CBD toxicity in mice found that prolonged CBD consumption increased liver enzymes.

There haven’t been enough studies on CBD’s long-term effects in humans, but elevated liver enzymes have been observed in some cases.

CBD users generally report only a few side effects. They usually develop mild, well-tolerated side effects that gradually disappear after a few hours.

CBD Considerations and Precautions

You may experience CBD oil side effects when you’re first introducing CBD products to your body. Nevertheless, you can lessen your risk of experiencing adverse reactions by paying attention to these points.

Drug Interactions With CBD

CBD oil is relatively safe, but we strongly recommend talking to your primary care physician before using it. Your doctor is knowledgeable about your medical history and can assist you with making an educated decision.

This is especially important for people who take medications. It has been reported that CBD interacts with a variety of drugs. In addition to causing more unwanted side effects, the drug can either amplify or reduce its potency.

Pregnant Women and Lactating Moms

During pregnancy or breastfeeding, cannabinoids are known to cross the placenta and get into the breastmilk, potentially affecting the baby. Those who are breastfeeding or pregnant should steer clear of CBD.

However, if you would like to try CBD oil to treat a particular condition, we still recommend that you speak with your doctor first.

Liver Issues

The liver is responsible for metabolizing many different substances, including CBD oil. When the liver metabolizes CBD oil, it can increase the levels of certain liver enzymes. This can be a concern for people who have liver problems, as these enzymes can indicate liver damage.

For this reason, it’s best to avoid CBD oil or use it at low doses if you have liver problems.

We stress the importance of seeing a healthcare professional before using CBD, more so if you suffer from liver disease.

Hemp and Cannabis Allergies

The chances of an allergic reaction to cannabis and hemp are very rare, but they do occur. Some people who’ve had direct contact with the plant develop mild skin allergies, while others who have inhaled its pollen experience respiratory discomfort.

Put a small amount of CBD oil on your skin first, and then wait for 30 minutes to an hour to reduce the risk of an allergic reaction. You should consider seeing a doctor if you develop skin rashes and hives after applying the oil.

How Can I Avoid CBD Oil’s Side Effects?

The average user of CBD oil tolerates it well. As your body gets used to CBD, these side effects will go away on their own.

Nevertheless, these side effects can also be quite unpleasant, so you may want to follow these tips so you can minimize their severity.

Begin With the Lowest Dose You Can Manage

If you want your body to become accustomed to CBD, begin by taking the smallest dose possible and gradually increasing or decreasing it based on your needs.

For example, if the instruction is to take one dropper, you can take half a dropper over the next three to five days. If you didn’t see any positive changes, this is the time to adjust the CBD oil dosage slowly.

On the other hand, if you developed adverse reactions after taking only half a dropper, decrease your dose. Exercise patience and keep taking the medication consistently. Before long, you’ll find the correct amount for you.

Check the CBD Product’s Certificate of Analysis (CoA)

It’s imperative for CBD brands to have their products tested by third-party laboratories because the market lacks regulations regarding manufacturing standards. Third-party testing is conducted to ensure the examined batch contains no pesticides, solvent residues, artificial fertilizers, or other harmful substances.

To establish transparency, many CBD vendors publish their certificates directly on their websites.

Brands that can’t prove the quality and safety of their CBD oil shouldn’t be trusted.

Check Out Good and Bad Reviews Online

You can choose a good CBD oil by reading customer reviews. These reviews provide insight into the intended effects of the product, as well as possible side effects. Just to make sure you’re getting an unbiased picture, compare the reviews from a few third-party websites.

Don’t Fall For Unrealistic Promises

Beware of statements that sound too good to be true. Shady CBD vendors want to make you buy their products by luring you with outrageous claims. They will say their CBD oil can treat all illnesses while being the least expensive on the market.

CBD oils are generally expensive. The most reputable CBD brands invest money in purchasing high-quality, organic raw materials and top-of-the-line equipment. They also hire scientists who are knowledgeable about current extraction technologies and purification processes to prevent contamination with toxic materials.

And that takes money.

Whenever you see a CBD brand offering the cheapest CBD oil that has answers for all your health problems, avoid it. Besides violating FDA rules, they may also mislead consumers about their CBD products, especially if they fail to provide valid laboratory testing results.

Final Thoughts: CBD Oil Side Effects

It’s safe to take CBD oil every day. CBD oil helps relieve discomfort and promotes overall wellbeing. A lot of well-conducted studies have highlighted its therapeutic potential, but it doesn’t mean it doesn’t have any side effects.

Potential adverse reactions include drowsiness, lightheadedness, and dry mouth. It may even change bowel habits for some people as well as lower their blood pressure.

Despite these side effects, users are able to tolerate them well. Once the body gets used to CBD, the side effects usually disappear.

If you follow the precautions and considerations mentioned in this guide, you may not experience any of these side effects at all (well, maybe except for the dry mouth). Above all, always choose your CBD oil from reputable brands that make their products according to the highest standards and can prove them with legitimate certificates.


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