Cannabidiol (CBD)

Last Updated: September 28 2022

Like THC, CBD is a cannabinoid (a compound in cannabis). Unlike THC, CBD won’t get you high, but it shows promise as a treatment for epilepsy, anxiety, depression, pain, inflammation, cancer, and more. Unfortunately, as of 2022, human trials are still few.

Cannabidiol (CBD) is most often used for

What is CBD?

CBD (cannabidiol) is the second most abundant cannabinoid in cannabis, after THC (tetrahydrocannabinol).[1] Unlike THC, CBD won’t get you high; it’s typically used medicinally, not recreationally, with the four most commonly targeted conditions being pain, anxiety, depression, and sleep disorders.

What are CBD’s main benefits?

Human research on CBD has focused on two rare forms of epilepsy: Dravet syndrome and Lennox-Gastaut syndrome.[3] In humans and animals, CBD has shown promise as a treatment for a wide variety of ailments, notably anxiety,[4][5][6][7][8] depression,[6] pain,[9][10][11][12] inflammation,[13][14] and cancer.[15]

Unlike cannabis and THC, CBD doesn’t impair coordination, judgment, or memory.[16] In a Critical Review Report published in 2018, the World Health Organization concluded that there was “no evidence of recreational use of CBD or any public health-related problems associated with the use

What are CBD’s main drawbacks?

CBD’s adverse effects are usually minor, but they include lethargy, fatigue, sleepiness, fever, diarrhea, vomiting, decreased appetite, and increased levels of alanine aminotransferase (a marker of liver damage).[17][18][19]

Other drawbacks include a paucity of human evidence, the unreliability of most CBD products on the market, and the “gray area” legality of CBD products.

How does CBD work?

CBD works in myriad ways, which are still being explored. For instance, it may reduce pain and stress via the TRPV1 receptor,[21][22][23] stress and depression via the 5HTI-alpha receptor,[24][25] and inflammation via the A2A receptors.[26]

Unfortunately, CBD seems to work better in combination with THC.

What else is Cannabidiol (CBD) known as?
Note that Cannabidiol (CBD) is also known as:
  • Cannabidiol
  • Epidiolex
  • CBD
Cannabidiol (CBD) should not be confused with:
  • THC
  • Cannabis
  • Sativex
Dosage information

The only CBD product approved in the U.S. is an epillectic drug: Epidiolex® is a solution (100 mg of CBD per milliliter) taken orally, preferably with food. The starting dosage is 2.5 mg per kilogram of body weight twice per day (so 5 mg/kg/day). The maximum dosage is 10 mg/kg twice per day (so 20 mg/kg/day). In people with hepatic impairment, the dosage is reduced.

Since (i) dosages in studies are all over the place, (ii) a CBD product’s label will very often overstate or understate this product’s CBD content,[93][94] and (iii) high-fat and high-calorie meals can greatly increase CBD absorption,[49] properly dosing CBD products is very, very difficult.

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