HHC (hexahydrocannabinol) is a semi-synthetic cannabinoid that is made in laboratories, usually from CBD extracted from hemp, and it gets people high in a similar way to THC. It can also make a cannabis drug screen come back positive. Since 6 December 2025 it has been under international control in Schedule II of the UN 1971 Convention on Psychotropic Substances, and many European countries had banned it before then.
Key facts
- What it is
- A hydrogenated form of THC (C21H32O2). Commercial HHC is semi-synthetic.
- Intoxicating?
- Yes. In a small controlled study, its effects were comparable to THC's (Höfert et al., 2025).
- Drug tests
- HHC cross-reacts with standard THC immunoassay screens in urine and saliva (Helander et al., 2024)
- UN status
- Schedule II of the 1971 Convention since 6 December 2025, after a vote in March 2025
- Europe, as of October 2026
- Controlled in Switzerland, Germany, France, Austria, Czechia, Denmark, Sweden, Norway and Finland. In the UK a draft order would make it Class B (see the table below).
- Formula Swiss
- We have never sold HHC
What is HHC?
HHC stands for hexahydrocannabinol. Chemically it is THC with two extra hydrogen atoms: hydrogenation saturates the one carbon–carbon double bond in THC's cyclohexene ring, and the aromatic ring stays unchanged. The result is a molecule with the formula C21H32O2 (molar mass about 316.5 g/mol), which exists as two forms, (9R)-HHC and (9S)-HHC.
Only traces of HHC have been reported in the cannabis plant. The HHC sold in shops is made by chemically converting CBD from hemp into THC-type compounds and then hydrogenating them, which is why it is called semi-synthetic. The production method affects which by-products end up in the final product, and products have been found to vary.
HHC appeared on the European market in 2022. By the time the UN placed it under control, 56 countries and territories had reported it to UNODC, which describes it as the first semi-synthetic cannabinoid under international control.
Does HHC get you high?
Yes. HHC acts on the same CB1 receptor as THC, and it is intoxicating. In a small controlled study at the University of Leipzig, six volunteers took HHC. The researchers measured how the body absorbed and broke it down, asked the volunteers to rate their "high", and ran balance and walking tests. Overall, the results were broadly comparable to THC. They varied a lot between people and with how HHC was taken (Höfert et al., 2025). The study was small and was not blinded or randomised.
In an online survey of 109 people who had used HHC, most described relaxation and euphoria. About 17% reported adverse effects, and about 20% of those who had stopped reported withdrawal symptoms (Ferretti et al., 2024). These are self-reports, not controlled evidence.
What are the risks of HHC?
The clearest data come from poison centres. French poison centres recorded 37 cases of self-reported HHC exposure between January 2022 and May 2023. Symptoms were mainly neurological (85%) and cardiovascular (61%), followed by gastrointestinal, psychiatric and eye symptoms. 59% of patients were hospitalised, and two cases were severe; all patients whose outcome was known recovered (Labadie et al., 2024). Only six patients had their blood or urine tested, and some had THC in their system too, so the series can't show how often these effects occur.
Beyond that, little is known:
- There are no long-term studies of repeated use.
- Effects in pregnancy haven't been studied.
- Because HHC is made by chemical conversion, products can differ in purity and in the mix of the two HHC forms.
Will HHC fail a drug test?
It can. Most cannabis drug tests start with an immunoassay screen, which uses antibodies designed to detect THC or its main metabolite, THC-COOH. HHC and its metabolites are similar enough to cross-react with these antibodies.
Researchers at Karolinska University Hospital in Stockholm reported that false-positive THC screens in saliva and urine samples rose from under 2% to over 10% as HHC spread in Sweden. Spiking experiments confirmed that HHC, its metabolite HHC-COOH and several related compounds trigger the screens (Helander et al., 2024).
| Test stage | What happens with HHC |
|---|---|
| Immunoassay screen (urine, saliva) | Can come back positive for THC because of cross-reactivity. A screen can't tell HHC from THC. |
| Confirmation by mass spectrometry | Measures specific compounds. Laboratories can identify HHC and its metabolites separately from THC, and some HHC metabolites can serve as clear markers of HHC use (Höfert et al., 2026). |
| Detection time | Not well established. Studies so far are too small to give reliable detection windows. |
In practice, using HHC can get you flagged for cannabis at work, at the roadside or in a treatment programme. In countries where HHC is now a controlled drug, a confirmed result can have legal consequences of its own. For how non-intoxicating CBD products relate to drug tests, see CBD, drug tests and driving.
Is HHC legal? (October 2026)
Mostly not, as of October 2026. In March 2025, at its 68th session, the UN Commission on Narcotic Drugs voted to add HHC to Schedule II of the 1971 Convention on Psychotropic Substances. The decision took effect on 6 December 2025. Countries that are party to the Convention must control HHC, and most European countries had already banned it nationally. The table shows the status we found in each country's official legal texts on 6 October 2026. Laws change, so check the linked source before relying on it.
| Country or level | Status of HHC | Primary source |
|---|---|---|
| UN | Schedule II of the 1971 Convention since 6 December 2025 (CND vote, March 2025) | UNODC |
| EU | No separate EU-wide HHC law. Each member state controls it under national drug law, in line with the UN listing. | UNODC |
| United Kingdom | Not yet listed in the Misuse of Drugs Act 1971. A draft Misuse of Drugs Act 1971 (Amendment) Order 2026, laid before Parliament, would make HHC a Class B drug. | Draft Order 2026 |
| Switzerland | Controlled since 31 March 2023: listed in schedule e of the narcotics list ordinance (BetmVV-EDI) and subject to the same controls as narcotics | BetmVV-EDI (SR 812.121.11) |
| Germany | Narcotic: listed in Annex II of the Narcotics Act (BtMG) | BtMG, Annex II |
| France | Classified as a narcotic (stupéfiant) since 13 June 2023. Production, sale and use are banned. | ANSM |
| Austria | Covered by the New Psychoactive Substances Ordinance (NPSV, Annex II, hexahydro-benzo[c]chromen-1-ol group), which bans manufacture, import and trade. | NPSV (RIS) |
| Czechia | Listed as a psychotropic substance (List 4) in Government Regulation 463/2013 | Regulation 463/2013 Sb. |
| Denmark | On List B of the Executive Order on Euphoriant Substances since 3 May 2023: medical and scientific use only | BEK 453/2023; BEK 405/2026 |
| Sweden | Narcotic (Swedish list I) since 11 July 2023 | LVFS 2011:10; date: Helander et al., 2024 |
| Norway | On the narcotics list, marked as prohibited under section 5 of the Narcotics Regulation | Narkotikaforskriften |
| Finland | Listed as a narcotic in Government Decree 543/2008 | Decree 543/2008 |
HHC is not the same as CBD. CBD does not get people high, and CBD itself is not on the UN schedules. HHC is a different, intoxicating substance, even though it is often made from CBD. Related compounds such as HHC-P and HHC acetate are listed separately in several countries. You can read more in which cannabinoids are psychoactive and how synthetic cannabinoids differ from plant-derived ones.
How is HHC different from THC and CBD?
| HHC | THC (delta-9) | CBD | |
|---|---|---|---|
| Origin | Semi-synthetic; only traces in the plant | Main cannabinoid in drug-type cannabis | Main cannabinoid in hemp |
| Intoxicating | Yes | Yes | No |
| Can trigger a THC drug screen | Yes, by cross-reactivity | Yes | Not by itself; products containing THC can |
| UN status (October 2026) | 1971 Convention, Schedule II | 1971 Convention, Schedule II | Not scheduled |
Some sellers say HHC is more stable than THC. We found no comparative studies showing this. For more on THC itself, see THC (tetrahydrocannabinol).
From our production
We don't sell HHC or any other cannabinoid that intoxicates, and we don't sell THCA products that turn into THC when heated.
— Robin Roy Krigslund-Hansen, co-founder and CEO
Frequently asked questions
What is HHC?
HHC (hexahydrocannabinol) is a hydrogenated form of THC. It is made in laboratories, usually from hemp-derived CBD, so it is called semi-synthetic. It is intoxicating, and since 6 December 2025 it has been in Schedule II of the UN 1971 Convention on Psychotropic Substances.
Is HHC legal in the UK?
As of 6 October 2026, HHC is not yet listed in the Misuse of Drugs Act 1971, but a draft order laid before Parliament in 2026 would make it a Class B drug.
Is HHC legal in Europe?
In much of Europe, no. Switzerland, Germany, France, Austria, Czechia, Denmark, Sweden, Norway and Finland control it, and since December 2025 it has been under UN control as well.
Does HHC get you high?
Yes. HHC acts on the same CB1 receptor as THC. In a small controlled study, its effects and how the body handled it were broadly comparable to THC, with large differences between people.
Will HHC fail a drug test?
It can. HHC and its metabolites cross-react with the immunoassay screens used for THC in urine and saliva, so a screen can come back positive for cannabis. Laboratory confirmation by mass spectrometry can then tell HHC apart from THC.
Is HHC the same as CBD?
No. HHC is often made from CBD, but it is a different, intoxicating compound under drug control. CBD does not cause a high and is not listed in the UN drug conventions.
Related guides
This article is for information only. It is not legal or medical advice, and it doesn't describe any product in our shop. Formula Swiss oils are cosmetics for external use. See our full disclaimer.
Last reviewed:
Sources
- UNODC Laboratory and Scientific Service (6 December 2025). CND decision on international control of hexahydrocannabinol (HHC) and carisoprodol enters into force.
- Höfert L et al. Preliminary pharmacokinetic and psychophysical investigations after controlled oral and inhalative consumption of hexahydrocannabinol (HHC). Sci Rep 2025;15:10086. doi:10.1038/s41598-025-93931-4
- Höfert L, Schirmer W et al. Preliminary pharmacokinetic investigations of hydroxylated metabolites after controlled inhalative and oral consumption of hexahydrocannabinol (HHC). Sci Rep 2026;16:22712. doi:10.1038/s41598-026-62767-x
- Helander A et al. Appearance of hexahydrocannabinols as recreational drugs and implications for cannabis drug testing: focus on HHC, HHC-P, HHC-O and HHC-H. Scand J Clin Lab Invest 2024;84(2):125–132. doi:10.1080/00365513.2024.2340039
- Labadie M et al. Hexahydrocannabinol poisoning reported to French poison centres. Clin Toxicol (Phila) 2024;62(2):112–119. doi:10.1080/15563650.2024.2318409
- Ferretti ML et al. A survey study of individuals using hexahydrocannabinol cannabis products: use patterns and perceived effects. Cannabis Cannabinoid Res 2024;9(5):e1385–e1394. doi:10.1089/can.2023.0143
- United Kingdom. Draft Misuse of Drugs Act 1971 (Amendment) Order 2026; Misuse of Drugs Act 1971, Schedule 2.
- Switzerland. Betäubungsmittelverzeichnisverordnung (BetmVV-EDI), SR 812.121.11, Annex 6 (schedule e), version of 13 March 2026.
- Germany. Betäubungsmittelgesetz (BtMG), Anlage II.
- France. ANSM (12 June 2023). L'ANSM classe l'hexahydrocannabinol (HHC) et deux de ses dérivés sur la liste des stupéfiants.
- Austria. Neue-Psychoaktive-Substanzen-Verordnung (NPSV), Annex II.
- Czechia. Nařízení vlády č. 463/2013 Sb., o seznamech návykových látek, Annex 4.
- Denmark. BEK nr 453 af 28/04/2023; BEK nr 405 af 26/03/2026 om euforiserende stoffer.
- Sweden. Läkemedelsverkets föreskrifter (LVFS 2011:10) om förteckningar över narkotika, consolidated up to HSLF-FS 2026:26.
- Norway. Forskrift om narkotika (narkotikaforskriften), narcotics list.
- Finland. Valtioneuvoston asetus huumausaineina pidettävistä aineista, valmisteista ja kasveista (543/2008).
