Cannabidiol (CBD) is naturally obtained cannabinoid from the cannabis plant. It is a compound that can also be found in the human body, also called endocannabinoids. It has become widely popular in the last couple of years for its potential in treating symptoms of various diseases.

Nevertheless, similar to other substances that you could introduce to your body, CBD comes with its own sets of side effects. While they are not necessarily serious, understanding them is important, especially if you are taking CBD or intend to do so in the future.

A review published in the Cannabis and Cannabinoid Research journal in 2017 documented the safety and side effects of the compound. It discussed its uses in various clinical studies, a lot of them concerns psychotic disorders and epilepsy. Its most common side effects include diarrhea, tiredness, and changes in both appetite and weight.

In general, the side effects appear fairly minor. The authors stated that CBD comes with a better side effect profile than other medications used in treating the above-mentioned illnesses.

A separate review published in the Current Drug Safety journal showed that the compound has no adverse effects as far as physiological parameters are concerned, such as blood pressure, heart rate, body temperature, psychomotor and psychological functions, food intake, and gastrointestinal transit.

A lot of the side effects of CBD have been observed in vitro or outside a living organism like Petri dishes and in studies involving animals. Some of the side effects known are inhibiting liver drug metabolism, reducing fertilization capacity, and altering cell viability.

In order to see if the side effects occur among humans, more studies involving human subjects is required.


Dry mouth sensations are common among many cannabis smokers. It usually happens after smoking a couple of joints which leave users the feeling of as if a cotton ball stays in the mouth. A glass of juice or water is a quick remedy to it.

As cannabis reduces secretion of saliva, dry mouth happens. Within the salivary glands are the cannabinoid receptors of the endocannabinoid system. These receptors interact with CBD, resulting in the dry mouth as salivary secretion is inhibited.


A study published in the International Journal of Neuroscience observed significant improvements among patients suffering dystonic movement disorders when CBD was administered to them.

Over a six week long period, the patients were given 100 to 600 mg daily oral doses of the CBD together with standard medications.

Nonetheless, while some improvements were seen in every patient, there were also some side effects noticed, including sedation, low blood pressure (hypotension), psychomotor slowing, dry mouth, and lightheadedness. Over 300 mg daily doses actually increased resting tremor and hypokinesia. It led researchers to believe that CBD can aggravate Parkinsonism effects among humans.

A study in 2014, meanwhile, published in the Journal of Psychopharmacology found that CBD can help patients with Parkinson’s disease by improving their quality of life.

You must consult your doctor prior to taking CBD, especially if taking pharmaceutical drugs.


CBD’s effect on drug metabolism within the liver is one side effect you need to be aware of. It is particularly crucial for folks taking prescribed medicines. The compound has been discovered to interact with the cytochrome P450 family, enzymes in charge of metabolizing drugs. The enzyme CYP3A4 metabolizes almost 60% of all pharmaceutical medicines, as well as CBD.

There are particular medicines that inhibit this enzyme that may slow down CBD breakdown and boost its physiological activity. Moreover, other drugs increase the levels of this enzyme, which result in a more rapid breakdown of the compound than normal.

On the other hand, CBD has benefits on liver enzymes, including improving levels of CYP1A1, an enzyme that can break down substances causing cancer including benzopyrene.