Synthetic cannabinoids: 12 of 223 'CBD' products hid one

Any molecule that acts on the CB1 and CB2 receptors of the endocannabinoid system is a cannabinoid. THC binds to CB1, and that is where its psychotropic effects come from. A "synthetic" cannabinoid is made by chemistry, where the others are extracted from the plant. In practice the word covers two very different families, and people often confuse it with CBD.

In semi-synthesis, a chemical reaction transforms a natural molecule: adding hydrogen to CBD gives H4-CBD, for example. Fully synthetic molecules often share no structure with THC whatsoever. They simply copy its action on the receptor.

A 2014 review in Drug and Alcohol Dependence explains why they are dangerous. Most of the molecules found in herbal blends bind more strongly to the CB1 receptor than THC, and depending on the molecule their effects are 2 to 100 times more potent.

People who search for "synthetic CBD" often mix up two things. Chemical synthesis can produce cannabidiol, and what comes out is the molecule found in hemp, trans-CBD. Since no new molecule is created, it falls outside what this article calls a synthetic cannabinoid.

Its safety as a food is a separate question. In July 2025, the European Food Safety Authority (EFSA) assessed a synthetic CBD of 99.5% purity, put forward as a food supplement at 30 mg per day. The manufacturer had not supplied the data requested, and EFSA concluded that its safety could not be established. Flowers and resins are plant products, and the CBD they contain is not synthesised. For the basics, see our article what is CBD.

The first of these molecules were made in university laboratories that studied the cannabinoid receptors. HU-210 was developed at the Hebrew University of Jerusalem, and the JWH series, JWH-018 among them, by chemist John W. Huffman's team. According to the same 2014 review, clandestine labs started spraying them onto dried plants in the early 2000s. The blends went on sale in Europe as Spice, labelled "not for human consumption".

In France, these molecules entered the CBD market through HHC, a semi-synthetic derivative that shops sold until its classification as a narcotic on 13 June 2023. At the time, the ANSM, France's medicines agency, reported growing use, "sometimes without the knowledge of users who think they are consuming another product, such as CBD". Our article on the HHC ban gives the full timeline.

Other molecules took its place straight away. In a decision of 22 May 2024, the ANSM added new cannabinoids to the narcotics list with effect from 3 June 2024: H4-CBD, H2-CBD, any molecule derived from the benzo[c]chromene core, THCP included, and eight fully synthetic cannabinoids. An amending decision of 3 June 2024, published the following day, leaves out CBN, CBNA, THCV up to 0.3% and the THCA of compliant hemp. Whatever you may read, the THCA in a legal flower is therefore not banned. A separate article covers H4-CBD.

The most recent arrivals are e-liquids sold as PTC, French slang for "blow your skull". On 6 February 2025, the ANSM reported new poisoning cases among teenagers hospitalised in 2024. These products are described in our feature on PTC.

Three addictovigilance centres and the toxicology laboratory of Lille University Hospital bought 223 products sold as CBD, first in July 2022 and again in April 2023. The purchases included flowers, resins, pollens, e-liquids and sweets, and 85% were meant to be inhaled. The results appear in a summary note from MILDECA, the body that coordinates French government drug policy.

For a buyer, four findings stand out:

• 12 of the 223 products, or 5.4%, contained HHC, Δ⁸-THC or H4-CBD without declaring it, mostly among the 2023 purchases.
• 28 products, or 12.5%, went over 0.3% Δ⁹-THC, the highest reaching 1.2%.
• Only one product in two stated its composition. Among those, 19% had a CBD content within 20% of the figure on the label.
• The laboratory found no medicine, no cutting agent and no other new psychoactive substance.

The authors point out that their sample is not representative of the whole market. Two years later, on 19 June 2025, the ANSM and Anses warned of several hundred poisonings recorded since early 2024. The products concerned were e-liquids, smoking products and foods such as oils, capsules or sweets. They contained HHC, HHC-O, H4-CBD, MDMB-PINACA or excess THC.

Potency comes first. A molecule 2 to 100 times more active than THC leaves no margin for error. Once it is sprayed on a flower or mixed into an e-liquid, the buyer has no way of knowing the dose.

Then come the observed effects. For the molecules listed in 2024, the ANSM reports vomiting, loss of consciousness, coma, convulsions, paranoia, anxiety, high blood pressure, rapid heart rate and cases of kidney failure. Users often found these effects stronger than those of cannabis.

The third risk is particular to the CBD market: the user has no idea. A person who buys a CBD flower expects no psychotropic effect. Sold a synthetic derivative in its place, they may drive, work or drink alcohol without suspecting a thing. Not one of these molecules was assessed before going on sale.

Looking at the product tells you nothing, since a sprayed flower looks like any other flower. Four checks lower the risk.

1. Read the composition. HHC, H4-CBD, "tetrahydrocannabidiol", "hydrogenated CBD", THCP, PTC and "Buddha Blue" are all names of narcotics. Be wary of any promise of an effect "close to THC" or "stronger than CBD".
2. Ask for the certificate of analysis of the batch, and check that its batch number matches the product. Δ⁹-THC must be at 0.30% or less, within the legal limit.
3. Look at which molecules the laboratory searched for. In the Lille study, liquid chromatography coupled to mass spectrometry picked up these derivatives. A certificate listing only CBD and THC tells you nothing about HHC or H4-CBD, which must appear in the list, marked "not detected", with a limit of detection.
4. Treat any unexpected effect as a warning. With heavy drowsiness, palpitations or anxiety, stop, keep the product so it can be tested and call a poison control centre. In an emergency in France, dial 15.

Every line of a certificate is explained in our guide to reading a certificate of analysis. The laboratory page describes the measurement methods.