Cannabis & Cannabinoids
Education only. This area explains the cannabis plant, its compounds and what research shows, separating approved medicines, ongoing research and unproven claims. It gives no dosing, buying or growing advice.
Cannabis and CBD can interact with medicines and are not suitable for everyone. Legal status differs by country and changes; pages say where that matters.
Start here: What Is Cannabis? Plant Biology and Common Terms
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Safety first
- These topics can involve legal restrictions, medicine interactions and serious health risks. Laws differ by country and change.
- Do not stop a prescribed medicine or delay care for a serious condition to try any of these.
- If someone may be poisoned or in a crisis, call emergency services first. See urgent help.
Overview
What this area covers
Cannabis and cannabinoids is one of the most searched and most misunderstood topics in natural health. The cannabis plant contains many compounds. NIDA says at least 125 are cannabinoids, including THC, which can be intoxicating, and CBD, which is not intoxicating like THC. [1] The FDA has not approved the plant for medical use, but it has approved a few drugs made from single cannabinoids. [2]This area is for education. It does not tell anyone what to use, how much, where to buy it or how to make it, and it does not replace advice from a doctor or pharmacist.
How the guides are organized
- Cannabis fundamentals. The plant, its history, the body's own cannabinoid system and the chemistry: what is cannabis, history and cultural use, the endocannabinoid system and cannabis chemistry.
- Cannabinoids. CBD, THC and CBG, CBN and other minor cannabinoids.
- Terpenes and varieties. Terpenes in cannabis and what strain names mean.
- Hemp and product education. Hemp foods, CBD product forms and labels and certificates of analysis.
- Research. Approved cannabinoid medicines, a clinical research overview, pain and sleep, neurological conditions and adverse effects and use disorder.
- Safety and regulation. Interactions and toxicology, pregnancy, teens and driving and laws by country.
- Comparisons. CBD vs THC, CBD vs CBG and CBN and hemp vs marijuana.
How we label the evidence
Each claim is tied to a source we read. We use plain labels: approved medicine (a regulator has approved a specific drug for a stated use), established, promising but limited, mixed, insufficient evidence, preclinical (cells/animals only), no good evidence of benefit, evidence of harm and marketing claim. Where we looked and found nothing usable, the page says "Proper evidence not found." Findings from cells or animals are not applied to people.Safety and legal pointers
- Children and edibles. Children eating cannabis edibles can be hospitalized. [1] The FDA says to take a child to a physician or emergency department if you reasonably suspect they swallowed a cannabis product. [3] In the US, Poison Help is 1-800-222-1222; see Poison Help by country.
- Medicines. Cannabis may interact with other medicines. [1] See how interactions work.
- Product quality. The FDA found many CBD products did not contain the amount of CBD claimed. [4]
- Laws. Laws differ by country, and in the US by state, and they change. Under US federal law marijuana is in Schedule I and hemp is defined by a 0.3 percent THC limit. [3] Nothing here is legal advice.
Explore Cannabis & Cannabinoids
Cannabis Fundamentals(4)The plant, its history, the endocannabinoid system and the chemistry of cannabinoids and terpenes.
- What Is Cannabis? Plant Biology and Common Terms
A plain guide to the cannabis plant: how it grows, what it contains, and what words like marijuana, hemp, THC, CBD and terpenes mean, with safety and legal pointers.
- Cannabis History and Cultural Use
A short, sourced history of cannabis from early use in Asia and the Old World through 19th-century Western medicine, 20th-century controls and modern research.
- The Endocannabinoid System: What It Is and What Is Known
What the endocannabinoid system is, how CB1 and CB2 receptors and the body's own cannabinoids work, and which claims about it are established, proposed or marketing.
- Cannabis Chemistry: Cannabinoids, Acids and Terpenes Explained
Plain-language chemistry of cannabis: cannabinoids, acid forms like THCA and CBDA, what heat changes, terpenes, and how strong the evidence for an entourage effect is.
Cannabinoids(3)CBD, THC, CBG, CBN and the minor cannabinoids, each described by what is known and what is not.
- CBD (Cannabidiol): What It Is, What Research Shows and Safety
What CBD is, the one approved CBD medicine, what research shows for anxiety, pain and sleep, and the liver, interaction, pregnancy and product-quality concerns.
- THC (Tetrahydrocannabinol): Effects, Research and Risks
What THC is, how it affects the body, the THC-based medicines the FDA has approved, and the short- and long-term risks, including edibles, driving and use disorder.
- CBG, CBN, CBC, THCV and Other Minor Cannabinoids
What is known and not known about CBG, CBN, CBC, THCV, delta-8 THC and other minor cannabinoids, with plain evidence labels and safety notes.
Terpenes & Varieties(2)Terpenes, cultivars, chemotypes and what strain names do and do not tell you.
- Terpenes in Cannabis: Myrcene, Limonene, Pinene, Linalool and Caryophyllene
What myrcene, limonene, pinene, linalool, caryophyllene and other cannabis terpenes are, what research does and does not show, and why product terpene profiles vary.
- Cultivars, Chemotypes and Strain Names: What the Labels Mean
What cultivar, chemotype, indica, sativa and strain names mean, and what genetic and lab studies show about whether those labels predict a product's chemistry or effects.
Hemp & Product Education(3)Hemp foods, CBD products, quality testing and how to read a certificate of analysis.
- Hemp Foods and Hemp Seed Oil
What hemp foods and hemp seed oil are, how they differ from CBD oil, what the US food regulator says, and what small human studies do and do not show.
- CBD Products: Oils, Topicals, Edibles and How to Read a Label
A plain guide to CBD oils, topicals and edibles: what the US regulator says, what lab studies found on labels, and what to check on a package before relying on it.
- Product Quality and Certificates of Analysis for Hemp and CBD Products
What lab studies found about mislabeled and contaminated CBD products, and how to read a certificate of analysis, including what a lab report can and cannot prove.
Cannabis Research(5)Approved cannabinoid medicines, clinical research by condition and adverse effects.
- Approved Cannabinoid Medicines: Epidiolex, Dronabinol, Nabilone and Nabiximols
Which cannabinoid medicines regulators have approved (Epidiolex, dronabinol, nabilone, nabiximols), for what, in which countries we verified, and the main warnings on th…
- Cannabis and Cannabinoid Clinical Research: What Systematic Reviews Show
What large systematic reviews say about cannabis and cannabinoid medicines for medical conditions, with evidence levels by condition, common side effects and the limits …
- Cannabis and Cannabinoids for Pain and Sleep: Research Summary
What systematic reviews and guidelines found for cannabis and cannabinoids in chronic pain and in sleep or insomnia, with evidence levels, side effects and where CBD fit…
- Cannabinoids and Neurological Conditions: Epilepsy, Spasticity and Other Research
What research shows for cannabinoids in epilepsy, multiple sclerosis spasticity, Parkinson's disease and anxiety, with approved uses, evidence levels, safety warnings an…
- Cannabis Adverse Effects, Cannabis Use Disorder and When to Seek Help
Plain facts on cannabis side effects, cannabis hyperemesis, psychosis risk, withdrawal and cannabis use disorder, with US emergency and treatment contacts as listed by N…
Safety & Regulation(3)Interactions, special groups, driving and how laws differ by country.
- Cannabis and CBD: Medicine Interactions and Toxicology
How CBD and THC can interact with other medicines, what is known about liver effects and acute toxicity, and where the evidence is thin. For education, not advice.
- Cannabis, Pregnancy, Breastfeeding, Teens and Driving
What regulators and research say about cannabis and CBD in pregnancy, breastfeeding, adolescence and driving, led by what to do if a child eats an edible.
- Cannabis and CBD Laws: How Regulation Differs by Country
How cannabis, hemp and CBD are regulated in the United States, Canada and the United Kingdom as read from official sources, with notes on what could not be verified.
Comparisons(3)CBD vs THC, CBG, CBN and hemp vs marijuana.
- CBD vs THC
A plain comparison of CBD and THC covering effects, approved medicines, risks, interactions, legal differences and why neither is a universal winner.
- CBD vs CBG and CBD vs CBN
Two short comparisons of CBD against CBG and against CBN, separating approved-medicine evidence for CBD from the limited human research and marketing claims for the mino…
- Hemp vs Marijuana
What separates hemp from marijuana in US law and in practice, how hemp seed foods differ from hemp-derived CBD and THC products, and why hemp-derived does not mean safe.
Related comparisons
Related Wellness Goals
Research connections
Our pages cite the studies and official sources behind each statement. For the underlying records, see the evidence page for this goal and the Research Library.
Specialty Topics Research and Evidence: How Much Research Exists and How to Read It Research Library Wellness Goals
Frequently asked questions
Is cannabis a medicine?
The FDA has not approved the cannabis plant for any medical use, but it has approved drugs containing individual cannabinoids for specific conditions. [2]
What is the difference between CBD and THC?
THC is mainly responsible for intoxicating effects. CBD is not intoxicating like THC but can cause side effects such as drowsiness and diarrhea. [1]
Is CBD legal?
It depends on the country and, in the US, on the state and how the product is made and sold. The FDA says adding CBD to a food or selling it as a dietary supplement is currently illegal federally. [4] Laws change; this is not legal advice.
Do CBD and cannabis products work for anxiety, pain or sleep?
Evidence varies by condition and product. Reviews find a small benefit for chronic pain and limited evidence for anxiety and sleep. [2]
Are CBD products what the label says?
Not always. The FDA tested some and many did not contain the CBD level claimed. [4]
Where do I start?
Start with what is cannabis, then CBD or THC. If you take medicines, read the interaction guide and talk with your pharmacist.
References
- National Institute on Drug Abuse (NIDA). Cannabis (Marijuana) DrugFacts. Read 2026-10-22.
- National Center for Complementary and Integrative Health (NCCIH). Cannabis (Marijuana) and Cannabinoids: What You Need To Know. Read 2026-10-22.
- US Food and Drug Administration. FDA Regulation of Cannabis and Cannabis-Derived Products, Including Cannabidiol (CBD): Questions and Answers. Read 2026-10-22.
- US Food and Drug Administration. What You Need to Know (And What We're Working to Find Out) About Products Containing Cannabis or Cannabis-derived Compounds, Including CBD. FDA page states content current as of 03/05/2020. Read 2026-10-22.
Content last updated . This section has not been medically reviewed.