CBD and Side Effects

CBD and Side Effects

Does CBD have side effects?

CBD has gained popularity in the health and beauty sectors because of its many benefits. Some have even recommended it as a valid alternative to pharmaceutical drugs in the context of certain health issues. According to a 2011 study on the safety and side effects of CBD, it is considered safe for consumption for both humans and animals. However, some may experience certain side effects, and while most are mild, it is important to know them.

Dry mouth

This is one of the most common phenomena associated with regular users of CBD. Your endocannabinoid system (ECS) has receptors in your salivary glands. So when you consume any cannabinoid, your ECS slows down the secretion of these glands. Studies have shown that your submandibular gland has cannabinoid receptors. This gland is responsible for over 60% of your saliva production. An endocannabinoid called anandamide interacts with these receptors to reduce the production of saliva. It does this by blocking the signals from your nervous system responsible for saliva secretion. You can easily overcome mouth dryness by drinking plenty of water or hydrating before, after, or while taking CBD.


Usually, CBD doesn't induce drowsiness. But the effects of CBD vary from person to person. Most of the time, CBD has a wake-inducing effect, causing you to feel more energetic and alert. Feelings of drowsiness have been reported, however, especially in users taking high doses. If you feel drowsy after taking CBD, it's best to avoid driving or operating heavy machinery. Since drowsiness is associated with higher doses of CBD, an easy fix might be to reduce the dosage.


Feeling lightheaded or dizzy is a rare and temporary side effect you may experience while using CBD. You may be able to alleviate this symptom by drinking beverages that contain caffeine. This helps your body get back to normal, but make sure to drink plenty of water since caffeine has an overall dehydrating effect as well.

Reduced blood pressure

A reduction in blood pressure is the cause of dizziness or lightheadedness in CBD users. CBD has been found to help people with heart disease and diabetes by lowering their blood pressure. Therefore, for healthy people with normal blood pressure, high doses of CBD may cause slight drops in blood pressure. If you're suffering from low blood pressure or you're undergoing treatment for it, you should see your doctor before taking CBD products.

Diarrhea and change in appetite & weight

A 2017 clinical study found that patients with psychotic disorders and epilepsy experienced side effects like diarrhea, fatigue, and changes in weight or appetite when exposed to CBD as a form of treatment. However, the study found that CBD had a better side effect profile compared to other drugs used in treating these conditions.

Effect on patients with movement disorders

In a 2009 study, patients with movement disorders were treated with standard medications alongside oral doses of CBD oil—between 100mg to 600mg daily for six weeks. These patients showed signs of improvement, but also experienced side effects such as:

  • low blood pressure
  • dryness of mouth
  • drowsiness and lightheadedness
  • psychomotor slowing (slowing of physical movements and thought processes)
  • increase in hypokinesia and resting tremor (with CBD doses above 300mg/day)
  • Effects on patients with Parkinson's disease

    Earlier research showed that high doses of CBD might worsen tremors and muscle movement in people with Parkinson's disease. However, a different study hinted that CBD could improve the quality of life in people suffering from Parkinson's disease. This shows that more research needs to be carried out regarding the effects of CBD on people living with Parkinson's disease.

    Effects on pregnant and breastfeeding women

    There is no sufficient and reliable information regarding the safety of taking CBD if you're pregnant or breastfeeding. To be on the safe side, avoid using CBD during pregnancy or breastfeeding.

    Interaction with pharmaceutical drugs

    Be careful with using CBD if you're on medication for any ailment or health issue. CBD has been shown to slow down the activities of certain liver enzymes responsible for the metabolism of certain pharmaceutical drugs. One enzyme of note is the cytochrome P450. The P450 enzyme system has over fifty enzymes that metabolize and eliminate drugs and toxic compounds. If you consume high amounts of CBD, it can neutralize the function of the P450 enzyme, since the same enzyme is required for CBD metabolism. Some pharmaceutical drugs also slow down the functioning of this enzyme, meaning the metabolism of CBD will also be slowed down. Meanwhile, some other pharmaceutical drugs can increase the levels of this enzyme, meaning a faster CBD metabolism. Whichever way, for your safety, always consult your doctor before using CBD in combination with any pharmaceutical drug.