CBD oil side effects range from mild to serious ones and are not to be taken lightly. The list of CBD side effects is a long one. Although vaping involves inhaling vapour, which are water molecules suspended in air, it may still cause your throat to get dry and lead to coughing. Some people believe CBD oil is safe and well-tolerated. Read about the side effects you can expect and what to be aware of.
Serious CBD Oil Side Effects Nobody Told You About
CBD oil — that magnificent, powerful phrase/product/cure that we have heard so much about. Everywhere you turn, there are praise and glory about its impact. However, rarely does one hear anything about the CBD oil side effects , even though they are extremely important.
The “bad boy” THC is to be partially blamed for this. The public has been focused on its effects for so long, even trying to ban cannabis entirely due to this psychoactive ingredient. That said, when CBD was discovered, people were inclined to believe cannabidiol is what makes cannabis such a powerful healer.
However, nothing is perfect, and neither is CBD. Contained in hemp oil or not, with or without some THC content, CBD oil comes with its fair share of downsides.
First, let’s take a quick look at what CBD is, and then you’ll find out everything there is to know about the negative side effects of CBD oil.
The Basics of CBD
What Is CBD?
CBD (cannabidiol) is just one of many cannabinoids in the cannabis plant. CBD structure remains absolutely the same whether we’re talking about CBD from hemp (Cannabis Sativa) or the ‘’regular cannabis” (Cannabis Indica).
There are over 100 cannabinoids within cannabis . These natural substances can bind to our own endocannabinoid system. This is why CBD is so efficient in the first place — our body recognizes it as a familiar substance.
Luckily for us, CBD research suggests new incredible health benefits every day.
What Is CBD Oil?
To better understand the CBD oil benefits and its effects, let’s explain what the oil actually represents.
There are two types of CBD oil :
- Pure CBD oil
- Full-spectrum CBD oil
The first one is guaranteed to have nothing else but CBD and carrier oil (olive, avocado, hemp seed oil, coconut oil, etc.). The latter comprises CBD, THC, and all the other cannabinoids you can find in a cannabis plant. Terpenes come into the picture as well.
CBD oil can be taken in various ways — as the oil itself and as a CBD oil-infused product ( CBD gummies , creams, lotions, patches, pills, and so on).
Less and More Common CBD Side Effects
Similarly to any medicine, CBD oil comes with a (long) list of warnings. And just like it is the case with any other drugs, the side effects may or may not exhibit themselves. Regardless of the reason, the fact remains that some people will endure the adverse effects.
One of the biggest reasons for this is that we are all different and that our bodies react individually to a stimulant. In addition to this, there are some things we can influence to avoid the side effects of CBD and get the maximum of its good sides.
Here are the most common disadvantages of CBD usage!
Whereas it is usually THC that is praised for a cannabis treatment for insomnia , CBD can make you drowsy as well. This is usually the case if you take a higher CBD dose than recommended.
On the other hand, if you wish to avoid these CBD negative side effects , just take a smaller dose .
CBD is not cut out for a sensitive stomach or palate.
If you take CBD in the form of oil drops, you could feel sick . This is especially true if you take it on an empty stomach. The general rule of thumb applies here as well — take your medicine half an hour or an hour after a meal. Drink plenty of water afterward.
Due to its application, the CBD cream side effects will include some other states, such as tiredness but hardly ever nausea.
Appetite Boost or Loss
Depending on what you’re trying to achieve, this could be great for you. CBD oil products are very much praised for increasing appetite, particularly in cancer patients.
Moreover , CBD oil for anxiety and reduced anxiety levels usually encourage people to eat more. The appetite-boosting quality is mainly connected with full-spectrum CBD oil.
Tingling and Numbness
CBD oil side effects include tingling on the lips or all over your body, especially if you’ve applied CBD oil topically. On the one hand, this is nothing to worry about and the sensation should disappear soon enough (within minutes). Many find it enjoyable, too, and it’s definitely one of the reasons people opt to try out CBD-infused lubes .
On the other hand, extreme or prolonged tingling sensation or numbness could be a sign you’ve exposed yourself to a higher dose of THC, so make sure you only buy CBD oil, flowers, etc. from reliable suppliers.
CBD Oil Side Effects on Eyes
Besides causing eye redness as one of the most common side effects, people with glaucoma should avoid using CBD products. Based on the American Academy of Ophthalmology report from 2019, CBD oil can worsen the symptoms of glaucoma .
Namely, the researchers found out that CBD can raise the eye’s pressure by 18% four hours after applying CBD drops.
On the other hand, drops containing only THC can decrease the eye’s pressure by 30% within eight hours.
Since more research is needed on the subject, it’s not advisable to use CBD products to treat glaucoma .
Dry mouth is one of the second most common CBD oil side effects . Basically, it is the feeling as if someone filled your mouth with cotton balls. It usually occurs if you’re using oil drops.
The scientific experiment behind it suggests that CBD inhibits the endocannabinoid receptors in our brain, which are responsible for saliva production.
Luckily, dry mouth is only temporary and easily solved — just take a big glass of water after consuming CBD oil.
Smoking CBD Oil Causes Sore Throat
Smoking or vaping CBD oil can result in a sore throat and raspy voice . As you know, smoking blunts or CBD pre-rolls makes your mouth and throat dry because you inhale toxic chemicals together with the tar from the hot and dry air.
The severity of the throat irritation will depend on the type of cannabis you vaped or smoked and your tolerance to smoke.
On top of that, smoking CBD oil burns your throat , so if you want to avoid these problematic side effects, you should:
- Stay hydrated
- Avoid spicy foods
- Gargle with warm salty water
- Reduce the frequency of smoking/vaping
Other alternative methods that can help you with a sore throat include:
- Avoiding energy drinks and caffeine
- Licking lemon or honey
- Drinking herb tea with fruits
- Buying a vaporizer that will get rid of the stale, dry air in your home
- Smoking outside of your home
CBD Vape Oil Side Effects
Vaping CBD oil can cause the following side effects :
- Feeling drowsy
- Decreased appetite
- Fatigue, discomfort, lack of energy
To avoid these side effects, make sure you’re vaping CBD correctly . First of all, avoid additives like diacetyl and vitamin E acetate . Next, buy your CBD from reliable brands, and lastly, determine the correct dosage.
Diarrhea is one of the side effects of CBD oil in humans as well as their pets. Here are the two main reasons why you could be experiencing this symptom:
- As with any other medication, your body needs some time to adjust to it.
- Since CBD oil alters your appetite , you may have changed your regular eating habits. Your gut gets revolted against the smaller or bigger food intake.
After one or two weeks, the symptoms should stop. Your body will adjust to CBD and the new eating pattern. If you are already suffering from diabetes or a similar appetite/weight loss condition, be very careful about maintaining your goal weight.
CBD Oil for Sleep Side Effects
On the one hand, CBD oil will help you fall asleep faster. On the other hand, you may experience very realistic dreams during the first couple of nights. Even nightmares .
What happens is that CBD allows you to enter a deep sleep stage called N3, delta sleep, or slow-wave sleep. Luckily, you should be free of bad dreams after two days or as much as it takes your brain to adjust to the new substance.
CBD Oil Side Effects on Kidneys
There are some opposite opinions on this one. According to one study , cannabis is beneficial for patients with advanced chronic kidney disease (CKD) . It helps them regulate the pain and exhibits no side issues.
Another research found that cannabis has an adverse effect , especially if it’s consumed via smoking. Patients were advised against medical marijuana, and CBD oil possibly could have the same effect.
What are the side effects of CBD for healthy people? Apparently, none. Those who did not suffer from kidney disease did not show any reduction in kidney functions while using cannabis.
Dizziness due to CBD oil typically occurs if one takes a higher dose than they should. The easiest way for this to happen is during vaping. It takes some skill to master it because it isn’t the same as smoking a joint.
Usually, people smoke concentrates rich in CBD, THC, and terpenes, so the “high” hits them rather unexpectedly.
To avoid side effects of vaping CBD , be moderate and careful about how you get your CBD vape oil . Dizziness could also be caused by low blood pressure .
Various studies have reported a link between cannabinoids and Parkinson’s , yet, we still don’t have enough evidence that shows it can be used as a potential treatment.
Parkinson’s patients are advised against using it if it interacts with some other medications because it can cause mood changes, diarrhea, and tiredness.
Keep in mind that if you use a too high dosage, it could even worsen the symptoms of the disease.
Grapefruit and CBD Oil Side Effects
Grapefruit and similar fruits contain certain substances that interact with CYP450 enzymes . In short, it prevents them from doing their job of dealing with the drugs we take.
If the enzymes are unable to do their part of breaking down the drugs in our bodies, the drug will end up in our liver, from where it will go into our bloodstream unprocessed. This means that you could end up with more drugs in your system than you are entitled to.
What about CBD tincture side effects ? CBD behaves similarly, plus it interferes with more enzymes (CYP3A4 and CYP2D6) and increases the drug level even more.
Even after you quit using CBD oil, your body won’t be able to use the drug normally until a few days have passed.
In this respect, the side effects will also show if a person is taking antidepressants, antihistamines, benzodiazepines, and statins.
To prevent the triggers in this case, be wary of the grapefruit warning on medications. Otherwise, CBD will turn the low dose of your medicine into a high dose.
CBD Oil Side Effects on Liver
This topic is pretty much intriguing, as it made some headlines.
Most articles that are against CBD oil usage rely on a mice study . Having been exposed to high CBD doses, they developed hepatotoxicity.
However, what is usually omitted from catchy headlines is the fact that CBD was given in high doses. For example, the doses equaled what would be three and ten times bigger doses than the recommended one for Epidiolex.
Essentially, Epidiolex is pure CBD oil . It does come with a label warning about CBD hemp oil side effects, saying it should be used with caution if one is taking liver meds. Still, taking a dosage three times bigger is worrying no matter which medicine we are talking about.
To sum up, side effects are possible, but they will occur only with extremely high doses if your liver is healthy.
Headaches and Migraines
When buying CBD oil of some kind, these CBD oil side effects may be listed on the label. In reality, the chances of CBD provoking headaches are very low.
According to one study , CBD does not cause headaches or migraines. On the contrary, it is recommended as a cure .
The cause of headaches may have more to do with any substances or solvents added to the oil. Given that not all CBD brands are reliable, sometimes a simple change of CBD brand will end the pain.
With CBD, you never know . Your body may develop tolerance to CBD effects after some time. This usually happens if your CBD oil contains THC.
In contrast, CBD is also known to cause reverse tolerance . This means you will need a smaller dose after using CBD for a long time.
To be safe, monitor your doses and reactions.
Low Blood Pressure
The reason for lowering blood pressure could be that CBD may act as a blood thinner . If you’re already on blood-thinning meds, the side effects of CBD oil can become very dangerous.
For example, even though CBD helps post-surgical pain and recovery, you shouldn’t be taking it one week before the operation.
CBD dilates blood vessels and is an excellent aid in preventing thrombosis or the formation of blood clots. But if you’re already using blood thinners, always consult with your doctor before you start experimenting with CBD.
CBD Oil Side Effects on Heart Palpitations
CBD could potentially help people with arrhythmia due to its anti-inflammatory properties, and many studies confirm this statement.
What’s more, CBD doesn’t have serious side effects when it comes to heart palpitations. However, its interaction with other arrhythmia medications can be potentially dangerous.
For example, CBD can interact with warfarin, nitrates, certain statins, beta-blockers, and calcium channel blockers. Therefore, it’s essential to consult with your doctor before trying anything on your own.
What Are the Side Effects of CBD Oil If You Are Allergic?
A cannabis allergy is a real thing. It manifests similarly to any other pollen allergy — runny nose, sneezing, rash, or itchy skin.
The allergy may be provoked by airborne allergens, handling the plant (people working in the industry are especially at risk), or even by eating some delicious edibles . Truth be told, CBD gummies’ side effects usually come as the consequence of overdosing on them, which is even more worrying if you are allergic to CBD.
While you could have a mild allergy to cannabis, it could make other allergies stronger, particularly food allergies .
If you are taking CBD oil for the first time, beware of these CBD oil side effects — dry cough, itchy eyes, sore throat, dry skin, blisters, hives, or watery eyes. Should you experience any of these, you may be having an allergic reaction to CBD oil .
CBD Oil Interactions with Other Drugs
Admittedly, the list is quite lengthy . We already mentioned some precautions when we discussed blood thinners and liver meds. Here is what to pay special attention to if you’re using CBD with other drugs.
It will interact with the following, so we strongly advise you against using CBD with:
CBD may interact with:
- Topiramate (Topamax)
- Sedative medications (CNS depressants), such as Nembutal, Luminal, Seconal, Duragesic, Sublimaze, morphine, Diprivan, Pentothal, and others.
- Rufinamide (Banzel).
Side effects of CBD hemp oil can also manifest if you use:
- Medications that increase/decrease the breakdown of other drugs by the liver :
Tagamet, Luvox, Prilosec, Ticlid, Topamax, Tegretol, Dilantin, Mycobutin, etc.
- Medications that decrease the breakdown of other drugs in the liver , such as:
Cordarone, Fortovase, Invirase, E-Mycin, Erythrocin, Cardizem, etc.
- Medications changed by the liver :
Endometrin, Prometrium, Adalat CC, Procardia XL, Sandimmune, Xanax, Norvasc, Biaxin, Sandimmune, erythromycin, Mevacor, Nizoral, Sporanox, Allegra, Halcion, Calan, Isoptin, and many others.
- Eslicarbazepine (Aptiom).
Does CBD Oil Have Side Effects in Pregnancy?
Short answer — nobody knows. The American College of Obstetricians and Gynecologists (ACOG) advises pregnant women against using cannabis in all its forms, CBD oil included.
So far, research on CBD oil dangers during pregnancy hasn’t been conducted. The existing studies all relied on cases when mothers-to-be were regular cannabis consumers.
They showed that smoking weed or eating cannabis during pregnancy is dangerous for the baby and may even cause stillbirth.
However, there is no evidence whatsoever that the use of CBD oil could cause the same consequences.
More Dangers of Using CBD Oil
This section has nothing to do with how your body processes CBD but rather with the side effects of CBD . To be more precise, it deals with whether or not you got what you paid for.
Namely, CBD oil regulations are far from picture-perfect. Unless you are buying from a reliable source, you may experience some hardships.
Here are a couple of reasons which may repel you from consuming cannabidiol.
- FDA — CBD oil is not FDA regulated. It isn’t even listed as an FDA-approved dietary supplement. Why? Most probably, because cannabis is still listed as a Schedule 1 drug. Hence, it’s a bit challenging to do the paperwork for something similar to heroin (which belongs to Schedule 1 too).
- Harmful substances — Another substance can sometimes be blamed for the negative side effects of CBD oil , given that there are lots of CBD oil-infused products on the market. Even if CBD oil is of perfect quality, it can be mixed with not-so-good ingredients.
In addition, less reputable companies may treat the land and plants with poisonous pesticides to have a higher yield. That’s why we always look at third party lab tests.
- Insufficient amount of CBD — Some CBD oils can have less CBD than it says on the label (and more carrier oil). Even worse, if you change the product but keep the dosage, you could overdose and experience all the negative side effects of CBD.
- Traces of THC — Some pure CBD oils can contain THC (even though they don’t have to). This is especially dangerous if pure CBD oil is recommended for a child because THC can severely affect the young brain.
In addition to that, THC can make you positive on a drug test as it lingers in your system for a long time. Not all drug tests can discover THC , though.
- Type of use — Interaction with other medications and similar side effects depends on how exactly you are taking your recommended dose. CBD lotions or creams shouldn’t provide you with high doses of CBD, for instance.
As for edibles, the adverse effects are less intense than vaping or smoking.
CBD Oil Side Effects Summary
Like every other drug, even the “magical” CBD oil can leave you with adverse side effects. Therefore you must always consult your doctor before taking any form of CBD oil.
To avoid any potential side effects, make sure you:
- Always consult your doctor before taking any form of CBD oil.
- Buy the oil only from reputable suppliers . The same applies if you decide to make your own CBD oil. Always use the best ingredients.
- Stick to the recommended dose . The majority of issues are connected with overdosing.
- Bear in mind how you take CBD oil — via CBD pills, oil, tincture, cream, edibles, or patches
- Monitor your body and the results you get.
We hope we managed to explain all there is about CBD and its side effects and that you can enjoy its advantages without any dangers to your health.
Is taking CBD every day bad for you?
Generally, CBD is considered safe. However, cannabidiol is not water. Every body is different and little research has been completed in order for CBD to be declared safe for everyday usage without any breaks.
CBD is not addictive because it doesn’t produce intoxicating effects. Some research even shows it can be used to treat addiction to cocaine and methamphetamine, and nicotine and cannabis .
CBD is most known for helping with:
- Reducing epilepsy seizures
- Reducing pain and inflammation
However, when it comes to dosage, consult with your doctor, especially if you’re taking other medications.
Can you have a bad reaction to CBD oil?
Yes, experiencing a bad reaction to CBD is possible. Although most people can tolerate CBD, using it can cause some side effects. The most common are the following:
- Appetite boost or loss
- Dry mouth and sore throat
- Low blood pressure
CBD can also cause tolerance and reverse tolerance. In other words, your body can develop a tolerance to the substance (if there’s THC in the oil). At the same time, if your body develops reverse tolerance, you’ll need smaller doses of CBD.
What drugs should not be taken with CBD?
CBD can interact with other drugs, which can cause various side effects. You should be cautious when mixing CBD with:
- Clobazam (Onfi)
- Topiramate (Topamax)
- Sedative medications (Nembutal, Luminal, Seconal, Duragesic, Sublimaze, morphine, Diprivan, Pentothal)
- Rufinamide (Banzel)
- Medications that increase/decrease the breakdown of other drugs by the liver
- Medications that decrease the breakdown of other drugs in the liver
- Medications changed by the liver
The mentioned drugs can cause severe CBD oil side effects when mixed together.
About the Author
A cannabis enthusiast, fascinated by the plant’s healing powers and the ever-changing world of the marijuana industry, trying to work out what is going on and let you know all the fun details — that’s my mission here. Keeping you high and healthy!
Why does vaping CBD make me cough and can I stop it?
Why does smoking my CBD vape pen hurt my throat and make me cough? Would it be different if I smoked a dry herb instead?
Avik Das (Wednesday, June 16, 2021):
Numerous reasons play roles if you cough during CBD vaping. One major reason for making you cough could be the presence of terpenes in it or even certain types of vape juice. Terpenes are usually present in both full-spectrum and broad-spectrum CBD vaping liquids. Terpenes cause itching in the throat, resulting in cough. If you are a novice in vaping, then coughing could happen as well until you get used to it.
Osasere Okunloye (Monday, December 27, 2021):
It could be because of several reasons:
- Full spectrum CBD contains other cannabinoids like terpenes which can make you cough.
- Vaping can cause dehydration of your throat and make you cough
- Underlying respiratory and cardiovascular conditions can also make you cough when vaping.
If you are a new vaper, you might need time to adjust. Also make sure you use lab-tested, high-quality pure hemp extract CBD e-liquid.
Is There Another Way To Take CBD To Avoid Coughing From Vaping?
Yes, Cannabotech has developed a unique M²CBD formula which contains a blend of CBD oil and functional mushrooms. This formula is used in all of Cannabotech products to help you relax, and unwind, while supporting your Endocannabinoid and immune system simultaneously.
7 CBD Oil Side Effects You Should Watch Out For
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CBD oil is believed to be generally safe and well-tolerated, but it is not free of side effects. Read on to learn which adverse effects you should watch out for when using CBD oil, how the delivery form influences them, and what you can do to reduce your risk.
CBD Oil Side Effects
First, it is important to remember that CBD oil is considered experimental and investigational and far more clinical studies are needed before we can make any firm conclusions about its supposed benefits .
Similarly, it’s an insufficiently investigated supplement with a relatively unknown safety profile. The list of side effects listed in this article is, therefore, not a definite one.
So, make sure to speak with your doctor before starting on a CBD oil regimen.
With the recent legalization of CBD oil in many states worldwide, its popularity is booming and people are taking it for not only its FDA-approved use for seizures, but also conditions such as :
An advantage of CBD oil is that it’s considered generally safer and causes fewer adverse effects than the drugs typically used for these conditions. Chronic doses of up to 1500 mg/day were tolerated well in multiple studies [3+, 4].
Unlike THC, CBD doesn’t cause behavioral and psychological side effects. What’s more, it may even reduce some of them such as anxiety, psychosis, and memory loss [5, 6, 7, 8].
CBD oil is believed to cause fewer side effects than THC and most prescription drugs, even at high doses.
Nevertheless, there are some potential side effects of CBD oil that you should watch out for. Below is a detailed overview of the most common ones.
1) Dry Mouth
Whether you use them for recreational or medicinal purposes, cannabis products will often make your mouth feel as if it were stuffed with cotton balls. Almost 12% of 1500 people responding to a survey about CBD use experienced dry mouth, making it the most common adverse effect .
Stimulation of the CB1 and CB2 receptors in the salivary glands reduces saliva secretion, which makes the mouth feel dry. The well-known cannabis compound THC activates these receptors directly. In turn, CBD raises the levels of an activator naturally produced in the body – the cannabinoid anandamide [9, 10, 11, 12].
2) Digestive Issues
Both CBD oil supplements and the FDA-approved CBD medicine Epidiolex have been reported to cause digestive issues such as [2, 4]:
- Nausea and vomiting
- Increased or reduced appetite
- Weight loss or gain
Because preliminary research suggests that CBD improves rather than causes nausea and diarrhea, these effects most likely result from the irritating effects of other ingredients (e.g., carrier oils) on the bowels [13, 14, 15].
Alternatively, the loose regulation of supplements may allow for excessive CBD levels in products or harmful contaminants such as pesticides, heavy metals, and solvents [16+, 17].
In turn, the endocannabinoid system has a role in promoting appetite. The mixed effects of CBD on appetite and weight seen in different studies may be due to its dual effect: it blocks the CB1 and CB2 receptors but boosts the levels of their activator anandamide [18, 19, 11].
If you experience digestive issues from using CBD oil, tell your doctor. He or she may recommend reducing the dose or shifting to another brand.
Contaminants and additives are likely responsible for the digestive side effects of low-quality CBD oil: nausea, vomiting, diarrhea, and appetite and weight changes.
3) Drowsiness and Fatigue
People taking CBD oil often report feeling sleepy and tired. Indeed, this side effect was observed in early clinical trials and one of the most common uses of CBD oil is to improve sleep disorders [20+].
If the symptoms are very severe, you shouldn’t drive or operate heavy machinery.
The effect of CBD on sleep seems to be biphasic: high doses may increase sleeping time, lower amounts may promote wakefulness. Additionally, levels of endocannabinoid receptors depend on the circadian rhythm. This may explain why CBD tends to cause drowsiness later in the day but has the opposite effect in the morning [21, 22, 23].
CBD oil may make you feel sleepy, especially if you take high doses at night. Low morning doses, on the contrary, seem to increase wakefulness.
High doses of CBD lowered blood pressure in a small trial on 9 people. In turn, THC seems to have a more complex effect: it slightly raises blood pressure in people lying down but increases the risk of sudden blood pressure drops when standing up [24, 25+].
As a result, a common adverse effect of CBD – both alone and with equal amounts of THC (nabiximols) – is feeling dizzy and light-headed [26, 27, 28].
If your blood pressure drops too much, you may faint. The risk is especially high in people diagnosed with low blood pressure or on blood pressure medications – such as diuretics, ACE inhibitors, and beta-blockers. These people should be especially cautious with CBD oil and never try it out without discussing it with their doctor.
CBD oil, alone or with THC, may reduce blood pressure. This can make you feel dizzy and light-headed, especially if you are prone to blood pressure drops.
5) Possible Liver Damage
Several trials testing CBD for seizures found possible liver damage (high transaminases ALT and AST) in 9-25% of the people. The risk increased with the dose and was highest in people also taking the anti-seizure drug valproate, which is known to cause liver injuries [29+, 30, 31, 32, 33, 34].
Similarly, CBD caused signs of liver toxicity (high transaminases, alkaline phosphatase, and bilirubin) in mice and dogs. However, the doses were generally higher than those used in human trials [35, 36, 37].
Make sure to talk to your doctor, especially if you are taking valproate, and never exceed the recommended CBD oil dose to reduce your risk of liver damage.
CBD oil may cause liver damage at very high doses and in people prescribed the anti-seizure drug valproate.
CBD is often used to curb anxiety, although research suggests it has “inverted U-shaped” effects: moderate doses, but not low or high amounts, may be effective for a range of anxiety disorders and stressful situations [38, 39].
In contrast, very high doses may even trigger anxiety and irritability. This was the case in 7-9% of the children in 2 clinical trials using CBD for seizures and autism [40, 41].
The effect probably involves the TRPV1 receptor, the activation of which increases the brain’s response to stressful situations .
CBD boosts the naturally-produced cannabinoid anandamide. While moderate anandamide levels activate CB1 receptors and curb anxiety, high amounts may worsen it by binding to TRPV1. CBD also activates this receptor directly, further contributing to the potential anxiety-triggering effects [43, 44, 11, 45].
7) Immune Suppression
CBD may reduce the immune response. It prevents T cells from dividing, migrating to inflammation sites, and producing pro-inflammatory cytokines. This may be beneficial in people with autoimmune conditions such as rheumatoid arthritis or multiple sclerosis [46, 47, 48, 49, 50, 51, 52].
The downside of blocking the immune response is that it may make people with weakened immune systems more prone to infections. Thus, people on immunosuppressants or with conditions such as HIV, diabetes, and Down syndrome might want to avoid it .
CBD oil seems to reduce the immune response, which may make people with a weak immune system more prone to infections.
CBD didn’t damage the kidneys in clinical trials. In fact, researchers believed it protected against kidney injury and inflammation in numerous animal studies [54, 55, 56, 57, 58]. Remember that larger and better designed clinical trials are needed before these findings are conclusive.
Though more clinical trials are needed, the current evidence suggests CBD oil will not harm your kidneys at normal doses.
On the other hand, people with kidney disease should probably avoid THC-containing medical marijuana without consulting a doctor.
According to a recent review, THC may worsen kidney health and increase urination by activating CB1 receptors. Remember that, unlike THC, CBD blocks these receptors. However, CBD may indirectly activate them by increasing anandamide levels in the body [59+].
Lastly, avoid synthetic cannabinoids at all costs (products like “spice” and “K2” sold in smoke shops). These chemicals caused sudden and severe kidney injury in several cases [59+].
Unlike THC and synthetic cannabinoids, CBD oil probably does not cause side effects on the kidneys; some researchers believe it might even be protective.
Are You at Risk of CBD Oil Side Effects?
CBD altered the levels of two drug transporters in placental cells. This suggests that taking CBD oil during pregnancy may increase the exposure of the fetus to any drugs that the mother takes. Pregnant women should avoid CBD oil in any case, since safety data are lacking .
Taking THC-containing CBD oil during pregnancy and breastfeeding is particularly dangerous, since THC may reduce growth and cause brain developmental anomalies in babies [61+].
Because there are no studies testing its safety in children below 2 years old, it’s better to avoid giving them CBD oil unless prescribed by a doctor.
CBD is thought to be safe in older children, but they may be more sensitive to THC and toxic contaminants such as heavy metals and pesticides than adults. Be sure to use high-quality, THC-free CBD in children and consult the doctor first.
Pregnant women and children under 2 years old should avoid CBD oil due to the lack of safety data; THC during pregnancy is known to be dangerous.
Most drugs are broken down by liver enzymes. Among them, cytochrome (CYP) P450 plays a key role. A single CBD dose blocks several CYP enzymes, such as:
By doing so, it may slow the breakdown of several drugs and enhance their effects [62, 63, 64, 65, 66].
Indeed, CBD reduced the breakdown of the sedative hexobarbital, the anti-seizure drug clobazam, and the blood thinner warfarin in humans. It had the same effect on the immunosuppressant cyclosporin and the cannabis compound THC in cells [67, 68, 69, 70].
On the other hand, repeated CBD doses can increase the levels of some enzymes of this group and reduce the effects of the drugs they break down [71, 72, 73, 74].
Plus, CBD itself is broken down by CYP enzymes, especially by CYP34A and CYP2C19. Drugs that block these enzymes (such as ketoconazole and ritonavir) will enhance its effects, while those that activate them (such as phenobarbital and rifampicin) will have the opposite effect [75, 4].
If you are on prescription medication and plan to use CBD oil, ask your doctor about potential interactions and dose readjustment. Additionally, avoid combining CBD oil with grapefruit or other supplements that block the same liver enzymes (such as St John’s wort or watercress).
CBD oil can block or activate liver enzymes that metabolize drugs. This may increase the side effects of both CBD oil and the medication you’re taking.
How Does the Delivery Form Influence CBD Oil Side Effects?
While rapid-release forms (mouth sprays and oil tinctures) deliver CBD directly into your bloodstream, slow-release forms (capsules, edibles, and teas) have to pass your digestive system first. This means their ingredients may irritate your bowels and give you nausea and diarrhea [76+, 77].
However, rapid-release forms will release CBD faster, so you may experience both wanted and unwanted effects sooner [76+, 77].
And since tinctures and sprays are directly applied in the mouth, they will quickly reach the salivary glands and cause dry mouth. Mouth sprays may also cause a stinging sensation and even burns, especially if they contain alcohol [9, 78].
Capsules and edibles are more likely to cause digestive side effects, while mouth sprays and tinctures more frequently cause dry mouth.
Vapes bypass the digestive system without irritating your bowels, but they may trigger the other adverse effects faster [76+, 77].
Vaping is considered safer than smoking cigarettes or joints because the oil is heated at lower temperatures that produce fewer toxic byproducts [76+ 79].
However, the additives used as flavorings and thinning agents in vaping oils may still pose some hazards. Although they are normally food-grade, they may release harmful compounds (including the cancer-causing formaldehyde) when vaporized. Their heavy use may lead to [80, 79, 81+]:
- Dry throat
- Lung injury
- Fat particles entering the lungs (lipoid pneumonia – rare)
For instance, one man developed severe lung damage from vaping CBD oil [82+].
Creams & Gels
Creams and gels act locally on the application site and don’t release CBD into the gut or bloodstream. This means they will not cause most of the adverse effects previously described [76+].
However, they may cause allergic reactions with itching, redness, and rashes on the skin. It’s important to note that the reactions can be caused by either CBD or other ingredients in the formulation [83+, 84+].
How to Reduce Your Risk of Side Effects from CBD Oil
1) Drink More Water
The best way to reduce dry mouth when using CBD oil is to drink plenty of water and other hydrating liquids before, during, and after consumption.
2) Find Additive-Free Products
You can reduce the risk of digestive issues by choosing forms that bypass the gut and directly release CBD into your bloodstream such as vapes, mouth sprays, and oil tinctures. High-quality oils without additives may also irritate your bowels less.
3) Take it Before Sleep
If you feel drowsy or light-headed after taking CBD oil, you may need to reduce the dose or take it only before sleep.
4) Increase Wakefulness Naturally
Drinking coffee or tea will help you both stay awake and raise your blood pressure, but it also causes many side effects. Try to get more sunlight first thing in the morning, as it will energize you and help you get better sleep at night. We talk about other natural ways to increase wakefulness in this post.
5) Support Your Liver
Avoid combining CBD with the anti-seizure drug valproate. Additionally, make sure not to exceed the dose and regularly monitor your liver function to reduce your risk of liver damage. Eggs (choline), artichokes, NAC, and probiotics also support liver health. Read more foods and supplements that are good for the liver here.
6) Don’t Take Megadoses
Only very high CBD doses may cause irritability. Make sure not to exceed the dose and try reducing it if you notice this symptom.
7) Monitor Your Immune Response
If you have a weakened immune system, you should consult your doctor before taking CBD oil. You may need to avoid CBD or take a lower dose.
Additionally, you may also want to look into balancing your Th1/Th2 immune response. If you have a slightly weaker immune system and are prone to allergies, you are probably Th2-dominant.
To reduce your risk of CBD oil side effects, avoid products with additives, drink plenty of water, get sunlight during the day, and support your liver and gut health.
Always make sure to speak with your physician before starting on a CBD oil regimen.
CBD oil is thought to be safe and most people seem to tolerate it well.
Low-quality products may contain additives and toxins that can irritate the lungs when vaped and the gut when taken orally. Choose high-quality products to reduce your risk.
Additionally, CBD oil can make you feel drowsy and lightheaded. If you feel tired after taking CBD oil, lower your dose or use it only before sleep. Look to also increase your wakefulness naturally by getting more sunlight during the day.
High doses may damage the liver, but likely only in people taking the anti-seizure medication valproate. Monitor your liver enzymes and look into natural ways to protect your liver.
Avoid CBD oil if you have a weak immune system, as it might make you more prone to infection.
If you take prescription drugs, consult your doctor. Many drugs can interact with CBD oil and increase the risk of side effects.
Pregnant women and children should avoid CBD oil until more safety data are available.
Some people have genes that make them more likely to experience inflammation. Check out SelfDecode’s Inflammation DNA Wellness Report for genetic-based diet, lifestyle, and supplement tips that can help reduce inflammation levels. The recommendations are personalized based on YOUR DNA.
About the Author
Carlos spent 9 years in the laboratory investigating mineral transport in plants. He then started working as a freelancer, mainly in science writing, editing, and consulting. Carlos is passionate about learning the mechanisms behind biological processes and communicating science to both academic and non-academic audiences. He strongly believes that scientific literacy is crucial to maintain a healthy lifestyle and avoid falling for scams.
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