Cannabidiol Oil (CBD) Safety, Side Effects, and Interactions with Other Drugs You Should Know Before Use

Common side effects and interaction of CBD need to know for the better outcomes


What is Cannabidiol?

A chemical compound. CBD present in Hemp Plant, Scientifically as Cannabis sativa or well-known Marijuana. Marijuana has more than eighty different chemical compounds. Among them, Tetrahydrocannabinol (THC) is more famous than CBD. In a Cannabis plant, the CBD amount is significantly less. But, these two chemicals are having some effects on the brain. 

CBD is usually formulated as oil. Sometimes it is available as a solid extract, vaporized liquid, and as an oil-based capsule. Presently, FDA approved only CBD oil product is Epidiolex. But we can find many CBD includes products such as beverages, cosmetics and supplements online. 

How does CBD work for me?

CBD is a cannabinoid. In our brain, there are many receptors on which many chemicals work. Among them, receptors called CB1 and CB2 are sensitive to cannabinoids. The principal chemical constituent of hemp, THC, works well on those receptors. Unlike THC, CBD does not directly work on those receptors. Another thing is that the CB1 receptor can be blocked by CBD and helps to reduce the harmful effects of THC. The ratio of THC: CBD is essential when formulating products such as Cannabidiol oil. 

CBD can work on non – cannabinoid receptors too. They are opioid receptors, dopamine receptors, and serotonin receptors. Opioid receptors are the unique aims of painkillers such as morphine and codeine. Dopamine receptors usually play a valuable role in cognitive regulations. Some studies ave done among the animals proved, CBD can activate serotonin receptors directly. 

Is CBD safe to use?

Nowadays, CBD is marketed mainly as a supplement. There are no regulations for the purity and safety of dietary supplements implemented by the FDA. We cannot ensure the exact amount of CBD available in that particular product. Perhaps, the product may include other chemicals. Based on recent research, found among 84 CBD products, one-fourth contained a minuscule amount of CBD than mentioned on the label. Eighteen products exceed the maximum amount of THC. 

If you are planning to take a CBD product, it would be better to consult a physician first. 

What are the Side Effects of CBD? 

Before going into the side effects, three things need considering. First, more research needs to evaluate the impact of CBD chronic use. Secondly, clinical trials have been done up to now in a small population. It should expand for a large population. Also, toxicological evaluation should be done in several aspects. Though CBD oil has beneficial effects on human health, we should take it at our own risk like other drugs because side effects that arise with CBD may not happen overnight. It will not affect everyone like same. When time goes by, side effects start slowly. Our body is different from others. If you take CBD oil, perhaps the following potential side effects may not be experienced at all. 


According to some customers’ experience, they felt the discomfort of the stomach and nausea after taking the CBD oil drops. Though CBD oil is used as an indication for this sickness, improper use causes sensitive stomachs. Also, it should not be used with an empty stomach. To avoid the nauseous feeling it is better to take it an hour after a meal. 

Dry mouth 

Some people feel dry after CBD oil. CBD itself has a cannabinoid effect. It can act on the endocannabinoid receptors and inhibits CB1 and CB2 receptors. That will lead to reducing the saliva production on salivary glands, and dry mouth occurs. 


Often high doses of CBD can cause dizziness. This is mostly happening with CBD vape pens. It has high absorption activity. If someone inhales a lot, this situation arises. Perhaps, this is medically insignificant. But dizziness can lead to low blood pressure, which should be highly considered. 


Several customers who complained reported drowsiness after taking CBD oil. On the one hand, this can be beneficial for people who suffer from sleep disorders. Anyway, high doses of the oil again cause drowsiness for all consumers. 

Mood and Appetite 

With CBD oil the mood and appetite of people can be altered. Usually, this will lead to a lack of appetite and low mood. Appetite can sometimes increase with CBD presence of high THC. 


This is a rare side effect. Individuals who do not have a strong stomach may experience diarrhea after taking CBD. Especially, someone who takes CBD oil with a full stomach can cause diarrhea. 


This is sometimes used in a patient with migraines as an alternative. So, there can be a chance to get a headache. In some cases, headaches come due to the harmful ingredients present in CBD oil

What are the interactions of CBD?

Our liver has many enzymes which are helpful to metabolize medications. A famous enzyme called Cytochrome P450(CYP450) is metabolizing many drugs. CBD can inhibit this enzyme. As a result, some drugs cause toxicity, and some lose their effectiveness within our bodies. 

Following are the potential drug interactions. 

Quinidine – drug use for correct the rhythms of the heart

Carbamazepine – anticonvulsant drug

Ketoconazole – use in fungal infections 

Pimozide – antipsychotic drug

Warfarin – blood thinner (therapeutic index of this drug is very narrow. With small changes of the dose can lead to toxicity or therapeutic failure)

Cyclosporine – immune-suppressive drug 

Some are mild interactions, and no need to adjust the medications. Sometimes you need to substitute the medicines or CBD taken with intervals. Our advice does not self-prescribe CBD; consult your physician first.