diprenyl-sulphide

Diprenyl sulphide: Aroma, Smell and Safety | PatientsCann UK Skip to main content Back to Sulphur Compounds Guide SDPS Diprenyl sulphide di-prenyl sulphide, bis(3-methylbut-2-enyl) sulphide pronounced: dy-PREN-il SUL-fide Two prenyl groups joined by sulphur. Smells closer to garlic than to skunk. Garlic & savouryFormula: C10H18SVery potent Aroma familyGarlic FormulaC10H18S Mass170.31 g/mol Main noteGarlic Diprenyl sulphide · 170.31 g/mol The molecule Chemical structure This is the accurate skeletal structure of Diprenyl sulphide, drawn from PubChem data. Each corner and line-end is a carbon atom. The yellow S marks sulphur, the atom that gives this whole family its powerful smell. GarlicAlliaceousSavouryOniony About What is Diprenyl sulphide? Diprenyl sulphide is built from two prenyl groups joined by a single sulphur atom. That shape is very close to the smell molecules garlic makes, which use two allyl groups instead of prenyl. Its smell is more garlic and onion than skunk. It is one of the compounds that first made scientists notice how much cannabis and garlic have in common. What the research says The Science Garlic’s sulphur compounds have been studied for years for possible heart and blood-vessel benefits. Because cannabis makes such similar molecules, researchers have raised the hopeful question of whether cannabis sulphur compounds might one day show benefits of their own. This is an early idea, not a proven fact. So far the science here is about smell and structure, not about treating any condition. Aroma snapshot How Diprenyl sulphide Smells Garlic & savoury family GarlicAlliaceousSavouryOniony Smell strength: Very potent Rich and savoury; carries clearly even at low levels. You might also smell it in: Garlic, onions, leeks and chives, which build their smells in a very similar way. Its role in the smell Part of the Whole Brings a savoury, garlicky layer to a cultivar’s aroma. It is one of the compounds that ties the smell of cannabis to the smell of the kitchen. Good to know A Note on Safety Diprenyl sulphide is an aroma compound, present in cannabis in trace amounts. It is not a medicine and has no dose of its own. What matters for you is the whole product and how it is prescribed. Always choose and adjust your medicine with your prescriber and pharmacist, never by smell alone. Questions Diprenyl sulphide: Common Questions Why does some cannabis smell like garlic? Compounds like diprenyl sulphide are built much like the smell molecules in garlic and onions. When a plant makes more of them, it can take on a savoury, garlicky edge. Does that mean cannabis has garlic’s health benefits? Not proven. The molecules look alike, which is why researchers are hopeful, but no study has yet shown that cannabis sulphur compounds share garlic’s effects. PreviousPrenyl thioacetate NextDiprenyl disulphide Back to full Sulphur Compounds Guide Important: This page is for education only. It is not medical advice. Research into cannabis sulphur compounds is very new, and most work so far is about smell, not treatment. The garlic comparison is about chemistry, not proven health effects. Always speak to your prescriber before changing your treatment. PatientsCann UK does not recommend any specific cannabis product. References Oswald, I.W.H., Ojeda, M.A., Pobanz, R.J., Koby, K.A., Buchanan, A.J., Del Rosso, J., Guzman, M.A. and Martin, T.J. (2021) ‘Identification of a new family of prenylated volatile sulfur compounds in cannabis revealed by comprehensive two-dimensional gas chromatography’, ACS Omega, 6(47), pp. 31667-31676. doi: 10.1021/acsomega.1c04196. Amagase, H. (2006) ‘Clarifying the real bioactive constituents of garlic’, Journal of Nutrition, 136(3), pp. 716S-725S. doi: 10.1093/jn/136.3.716S. Russo, E.B. (2011) ‘Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects’, British Journal of Pharmacology, 163(7), pp. 1344-1364. doi: 10.1111/j.1476-5381.2011.01238.x. National Center for Biotechnology Information (2025) PubChem Compound Database. Bethesda: U.S. National Library of Medicine. Available at: https://pubchem.ncbi.nlm.nih.gov (Accessed: 3 August 2026).

diprenyl-disulphide

Diprenyl disulphide: Aroma, Smell and Safety | PatientsCann UK Skip to main content Back to Sulphur Compounds Guide SDPDS Diprenyl disulphide di-prenyl disulphide pronounced: dy-PREN-il dy-SUL-fide Like diprenyl sulphide, but with two sulphur atoms. Deep, garlicky and long-lasting. Garlic & savouryFormula: C10H18S2Very potent Aroma familyGarlic FormulaC10H18S2 Mass202.38 g/mol Main noteGarlic Diprenyl disulphide · 202.38 g/mol The molecule Chemical structure This is the accurate skeletal structure of Diprenyl disulphide, drawn from PubChem data. Each corner and line-end is a carbon atom. The yellow S marks sulphur, the atom that gives this whole family its powerful smell. GarlicOnionySavouryAlliaceous About What is Diprenyl disulphide? Diprenyl disulphide is like diprenyl sulphide but with two sulphur atoms joined together in the middle. That extra sulphur makes the smell deeper and longer-lasting. It is a near mirror of diallyl disulphide, one of the most studied smell molecules in garlic. The main difference is the prenyl group in place of garlic’s allyl group. What the research says The Science Diallyl disulphide from garlic has been looked at for possible effects on blood pressure and blood vessels. The close match with diprenyl disulphide is what makes the cannabis-and-garlic comparison so striking. It is important to be clear: looking alike is not the same as acting alike. This stays a hopeful research direction, not a health claim. Aroma snapshot How Diprenyl disulphide Smells Garlic & savoury family GarlicOnionySavouryAlliaceous Smell strength: Very potent Deep and long-lasting; the double sulphur bond makes it cling. You might also smell it in: Cooked garlic and onion, which are rich in these two-sulphur “disulphide” smells. Its role in the smell Part of the Whole Adds a deep, clingy, savoury base note to the aroma. Two-sulphur compounds like this one tend to linger longer than lighter smells. Good to know A Note on Safety Diprenyl disulphide is an aroma compound, present in cannabis in trace amounts. It is not a medicine and has no dose of its own. What matters for you is the whole product and how it is prescribed. Always choose and adjust your medicine with your prescriber and pharmacist, never by smell alone. Questions Diprenyl disulphide: Common Questions What is the garlic molecule it copies? Diallyl disulphide. Garlic’s version uses an allyl group; the cannabis version uses a prenyl group. Otherwise they are built the same way, with two sulphur atoms in the middle. Is this why some cannabis smells strongly of garlic? Two-sulphur compounds like this one are deep and clingy. When a plant makes more of them, its savoury, garlicky side becomes easier to notice. PreviousDiprenyl sulphide NextPrenyl methyl sulphide Back to full Sulphur Compounds Guide Important: This page is for education only. It is not medical advice. Research into cannabis sulphur compounds is very new, and most work so far is about smell, not treatment. The garlic comparison is about chemistry, not proven health effects. Always speak to your prescriber before changing your treatment. PatientsCann UK does not recommend any specific cannabis product. References Oswald, I.W.H., Ojeda, M.A., Pobanz, R.J., Koby, K.A., Buchanan, A.J., Del Rosso, J., Guzman, M.A. and Martin, T.J. (2021) ‘Identification of a new family of prenylated volatile sulfur compounds in cannabis revealed by comprehensive two-dimensional gas chromatography’, ACS Omega, 6(47), pp. 31667-31676. doi: 10.1021/acsomega.1c04196. Amagase, H. (2006) ‘Clarifying the real bioactive constituents of garlic’, Journal of Nutrition, 136(3), pp. 716S-725S. doi: 10.1093/jn/136.3.716S. Russo, E.B. (2011) ‘Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects’, British Journal of Pharmacology, 163(7), pp. 1344-1364. doi: 10.1111/j.1476-5381.2011.01238.x. National Center for Biotechnology Information (2025) PubChem Compound Database. Bethesda: U.S. National Library of Medicine. Available at: https://pubchem.ncbi.nlm.nih.gov (Accessed: 3 August 2026).

dimethyl-trisulphide

Dimethyl trisulphide: Aroma, Smell and Safety | PatientsCann UK Skip to main content Back to Sulphur Compounds Guide SDMTS Dimethyl trisulphide dimethyl trisulphide, DMTS pronounced: dy-METH-il try-SUL-fide Three sulphur atoms in a row. A savoury, oniony smell found in cooked foods. Everyday sulphurFormula: C2H6S3Very potent Aroma familyEveryday FormulaC2H6S3 Mass126.31 g/mol Main noteSavoury Dimethyl trisulphide · 126.31 g/mol The molecule Chemical structure This is the accurate skeletal structure of Dimethyl trisulphide, drawn from PubChem data. Each corner and line-end is a carbon atom. The yellow S marks sulphur, the atom that gives this whole family its powerful smell. SavouryOnionCookedMeaty About What is Dimethyl trisulphide? Dimethyl trisulphide, or DMTS, has three sulphur atoms joined in a row. That gives it a strong, savoury, oniony smell. It is common in cooked foods, from fried onions to aged cheese. In cannabis it adds a savoury, cooked depth to the overall aroma. What the research says The Science Like DMS, DMTS is found widely in food, so its smell is well known. It is far more powerful than DMS thanks to those extra sulphur atoms. In cannabis it is one of several savoury sulphur notes that sit beneath the brighter skunk and fruit smells. Aroma snapshot How Dimethyl trisulphide Smells Everyday sulphur family SavouryOnionCookedMeaty Smell strength: Very potent Powerful and savoury; a little reads as onion or cooked meat. You might also smell it in: Cooked onion, aged cheese, cooked cabbage and some cooked meats. Its role in the smell Part of the Whole Deepens the savoury base of the aroma, adding a cooked, oniony richness under the sharper top-notes. Good to know A Note on Safety Dimethyl trisulphide is an aroma compound, present in cannabis in trace amounts. It is not a medicine and has no dose of its own. What matters for you is the whole product and how it is prescribed. Always choose and adjust your medicine with your prescriber and pharmacist, never by smell alone. Questions Dimethyl trisulphide: Common Questions Why does some cannabis smell savoury or oniony? Compounds like dimethyl trisulphide, also found in cooked onions and cheese, add a savoury, cooked depth. They sit under the sharper skunk and fruity smells. Is DMTS stronger than DMS? Yes. The extra sulphur atoms make dimethyl trisulphide much more powerful, which is why even a little smells strongly savoury. PreviousDimethyl sulphide Next3-Methyl-2-butene-1-thiol Back to full Sulphur Compounds Guide Important: This page is for education only. It is not medical advice. Research into cannabis sulphur compounds is very new, and most work so far is about smell, not treatment. The garlic comparison is about chemistry, not proven health effects. Always speak to your prescriber before changing your treatment. PatientsCann UK does not recommend any specific cannabis product. References Oswald, I.W.H., Ojeda, M.A., Pobanz, R.J., Koby, K.A., Buchanan, A.J., Del Rosso, J., Guzman, M.A. and Martin, T.J. (2021) ‘Identification of a new family of prenylated volatile sulfur compounds in cannabis revealed by comprehensive two-dimensional gas chromatography’, ACS Omega, 6(47), pp. 31667-31676. doi: 10.1021/acsomega.1c04196. Russo, E.B. (2011) ‘Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects’, British Journal of Pharmacology, 163(7), pp. 1344-1364. doi: 10.1111/j.1476-5381.2011.01238.x. National Center for Biotechnology Information (2025) PubChem Compound Database. Bethesda: U.S. National Library of Medicine. Available at: https://pubchem.ncbi.nlm.nih.gov (Accessed: 3 August 2026).

dimethyl-sulphide

Dimethyl sulphide: Aroma, Smell and Safety | PatientsCann UK Skip to main content Back to Sulphur Compounds Guide SDMS Dimethyl sulphide dimethyl sulphide, DMS pronounced: dy-METH-il SUL-fide A simple, everyday sulphur smell found across many foods. Everyday sulphurFormula: C2H6SModerately potent Aroma familyEveryday FormulaC2H6S Mass62.13 g/mol Main noteSweetish Dimethyl sulphide · 62.13 g/mol The molecule Chemical structure This is the accurate skeletal structure of Dimethyl sulphide, drawn from PubChem data. Each corner and line-end is a carbon atom. The yellow S marks sulphur, the atom that gives this whole family its powerful smell. SweetishCooked vegetableCabbageMarine About What is Dimethyl sulphide? Dimethyl sulphide, or DMS, is one of the simplest sulphur smells there is: two methyl groups either side of a single sulphur atom. It is everywhere in food and nature. You have smelled it in cooked sweetcorn and cabbage, in beer, and even in the sea air at the coast. In cannabis it adds a light, savoury background note. What the research says The Science Unlike the prenyl compounds, DMS is not special to cannabis. It turns up across the plant and food world, which is why it is so well understood. In cannabis it is a minor player, adding a soft savoury edge rather than a defining smell. Aroma snapshot How Dimethyl sulphide Smells Everyday sulphur family SweetishCooked vegetableCabbageMarine Smell strength: Moderately potent Familiar from cooking; sweetish at low levels, cabbagey when strong. You might also smell it in: Cooked sweetcorn, cabbage, the sea breeze, beer and truffles. Its role in the smell Part of the Whole Sits quietly in the background, adding a gentle savoury lift rather than a smell of its own. Good to know A Note on Safety Dimethyl sulphide is an aroma compound, present in cannabis in trace amounts. It is not a medicine and has no dose of its own. What matters for you is the whole product and how it is prescribed. Always choose and adjust your medicine with your prescriber and pharmacist, never by smell alone. Questions Dimethyl sulphide: Common Questions Is dimethyl sulphide unique to cannabis? No. It is one of the most common sulphur smells in nature, found in cooked vegetables, the sea and many drinks. In cannabis it plays only a small background role. Is it harmful? It is a normal, widespread food aroma present in trace amounts. It is the smell, not a medicine, and there is no known concern at these tiny levels. Previous3-Mercaptohexyl acetate NextDimethyl trisulphide Back to full Sulphur Compounds Guide Important: This page is for education only. It is not medical advice. Research into cannabis sulphur compounds is very new, and most work so far is about smell, not treatment. The garlic comparison is about chemistry, not proven health effects. Always speak to your prescriber before changing your treatment. PatientsCann UK does not recommend any specific cannabis product. References Oswald, I.W.H., Ojeda, M.A., Pobanz, R.J., Koby, K.A., Buchanan, A.J., Del Rosso, J., Guzman, M.A. and Martin, T.J. (2021) ‘Identification of a new family of prenylated volatile sulfur compounds in cannabis revealed by comprehensive two-dimensional gas chromatography’, ACS Omega, 6(47), pp. 31667-31676. doi: 10.1021/acsomega.1c04196. Russo, E.B. (2011) ‘Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects’, British Journal of Pharmacology, 163(7), pp. 1344-1364. doi: 10.1111/j.1476-5381.2011.01238.x. National Center for Biotechnology Information (2025) PubChem Compound Database. Bethesda: U.S. National Library of Medicine. Available at: https://pubchem.ncbi.nlm.nih.gov (Accessed: 3 August 2026).

3-mercaptohexyl-acetate

3-Mercaptohexyl acetate: Aroma, Smell and Safety | PatientsCann UK Skip to main content Back to Sulphur Compounds Guide S3-MHA 3-Mercaptohexyl acetate 3-mercaptohexyl acetate, 3-sulfanylhexyl acetate, 3-MHA pronounced: three mer-KAP-toh-HEX-il ASS-uh-tate The passion-fruit molecule. The acetate cousin of 3-MH, even more tropical. Tropical & fruityFormula: C8H16O2SExtremely potent Aroma familyTropical FormulaC8H16O2S Mass176.28 g/mol Main notePassion fruit 3-Sulfanylhexyl acetate · 176.28 g/mol The molecule Chemical structure This is the accurate skeletal structure of 3-Mercaptohexyl acetate, drawn from PubChem data. Each corner and line-end is a carbon atom. The yellow S marks sulphur, the atom that gives this whole family its powerful smell. Passion fruitTropicalFruityCitrus About What is 3-Mercaptohexyl acetate? 3-Mercaptohexyl acetate, or 3-MHA, is the acetate cousin of 3-MH. Adding the acetate group pushes the smell even further towards passion fruit and tropical punch. Like 3-MH, it is a star of flavour chemistry in wine and beer, and it was reported among the compounds behind fruity, exotic cannabis. What the research says The Science The 2023 study grouped 3-MHA with 3-MH as key drivers of tropical, fruity aromas in certain cultivars. The two often appear together. It is another extremely powerful smell, active at tiny concentrations. Aroma snapshot How 3-Mercaptohexyl acetate Smells Tropical & fruity family Passion fruitTropicalFruityCitrus Smell strength: Extremely potent An even punchier passion-fruit smell, powerful at trace levels. You might also smell it in: Passion fruit, tropical beers and white wines. Its role in the smell Part of the Whole Layers a ripe passion-fruit punch over the top of fruity cultivars, deepening their tropical character. Good to know A Note on Safety 3-Mercaptohexyl acetate is an aroma compound, present in cannabis in trace amounts. It is not a medicine and has no dose of its own. What matters for you is the whole product and how it is prescribed. Always choose and adjust your medicine with your prescriber and pharmacist, never by smell alone. Questions 3-Mercaptohexyl acetate: Common Questions What is the difference between 3-MH and 3-MHA? They are close cousins. 3-MHA has an extra acetate group, which shifts its smell from grapefruit towards passion fruit. They often occur together. Do these tropical smells mean the cannabis is stronger? No. Smell and strength are separate. A tropical aroma tells you about the plant’s sulphur compounds and terpenes, not about its cannabinoid content. Previous3-Mercaptohexan-1-ol NextDimethyl sulphide Back to full Sulphur Compounds Guide Important: This page is for education only. It is not medical advice. Research into cannabis sulphur compounds is very new, and most work so far is about smell, not treatment. The garlic comparison is about chemistry, not proven health effects. Always speak to your prescriber before changing your treatment. PatientsCann UK does not recommend any specific cannabis product. References Oswald, I.W.H., Ojeda, M.A., Pobanz, R.J., Koby, K.A., Buchanan, A.J., Del Rosso, J., Guzman, M.A. and Martin, T.J. (2021) ‘Identification of a new family of prenylated volatile sulfur compounds in cannabis revealed by comprehensive two-dimensional gas chromatography’, ACS Omega, 6(47), pp. 31667-31676. doi: 10.1021/acsomega.1c04196. Oswald, I.W.H. et al. (2023) ‘Minor, nonterpenoid volatile compounds drive the aroma differences of exotic cannabis’, ACS Omega, 8(36), pp. 39203-39216. Russo, E.B. (2011) ‘Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects’, British Journal of Pharmacology, 163(7), pp. 1344-1364. doi: 10.1111/j.1476-5381.2011.01238.x. National Center for Biotechnology Information (2025) PubChem Compound Database. Bethesda: U.S. National Library of Medicine. Available at: https://pubchem.ncbi.nlm.nih.gov (Accessed: 3 August 2026).

3 Mercaptohexanol

3-Mercaptohexan-1-ol: Aroma, Smell and Safety | PatientsCann UK Skip to main content Back to Sulphur Compounds Guide S3-MH 3-Mercaptohexan-1-ol 3-mercaptohexanol, 3-sulfanylhexan-1-ol, 3-MH pronounced: three mer-KAP-toh-HEX-an-ol The grapefruit molecule. A tropical, citrus thiol also famous in wine and beer. Tropical & fruityFormula: C6H14OSExtremely potent Aroma familyTropical FormulaC6H14OS Mass134.24 g/mol Main noteGrapefruit 3-Sulfanylhexan-1-ol · 134.24 g/mol The molecule Chemical structure This is the accurate skeletal structure of 3-Mercaptohexan-1-ol, drawn from PubChem data. Each corner and line-end is a carbon atom. The yellow S marks sulphur, the atom that gives this whole family its powerful smell. GrapefruitCitrusTropicalPassion fruit About What is 3-Mercaptohexan-1-ol? 3-Mercaptohexan-1-ol, or 3-MH, is a very different kind of sulphur compound. Instead of skunk or garlic, it smells of grapefruit, citrus and tropical fruit. It is well known outside cannabis. It is one of the molecules that give Sauvignon Blanc wine and certain hoppy beers their zesty, tropical lift. What the research says The Science A 2023 follow-up study reported that thiols like 3-MH help explain the fruity, tropical smell of some prized ‘exotic’ cannabis, a smell that terpenes alone could not account for. It is astonishingly powerful. The nose can detect it at parts per trillion, far below the level needed for most terpenes. Aroma snapshot How 3-Mercaptohexan-1-ol Smells Tropical & fruity family GrapefruitCitrusTropicalPassion fruit Smell strength: Extremely potent One of the most powerful smells known, detectable at parts per trillion. You might also smell it in: Sauvignon Blanc wine, tropical craft beers, grapefruit and passion fruit. Its role in the smell Part of the Whole Brings the bright, juicy, tropical top-notes to fruity cultivars, working hand in hand with citrus terpenes like limonene. Good to know A Note on Safety 3-Mercaptohexan-1-ol is an aroma compound, present in cannabis in trace amounts. It is not a medicine and has no dose of its own. What matters for you is the whole product and how it is prescribed. Always choose and adjust your medicine with your prescriber and pharmacist, never by smell alone. Questions 3-Mercaptohexan-1-ol: Common Questions Why does some cannabis smell of tropical fruit? Thiols such as 3-mercaptohexan-1-ol smell strongly of grapefruit and tropical fruit. A little goes a very long way, so even trace amounts can make a plant smell juicy and exotic. Is this the same molecule found in wine? Yes. 3-MH is one of the compounds that give Sauvignon Blanc wine and some tropical beers their grapefruit and passion fruit character. PreviousPrenyl methyl sulphide Next3-Mercaptohexyl acetate Back to full Sulphur Compounds Guide Important: This page is for education only. It is not medical advice. Research into cannabis sulphur compounds is very new, and most work so far is about smell, not treatment. The garlic comparison is about chemistry, not proven health effects. Always speak to your prescriber before changing your treatment. PatientsCann UK does not recommend any specific cannabis product. References Oswald, I.W.H., Ojeda, M.A., Pobanz, R.J., Koby, K.A., Buchanan, A.J., Del Rosso, J., Guzman, M.A. and Martin, T.J. (2021) ‘Identification of a new family of prenylated volatile sulfur compounds in cannabis revealed by comprehensive two-dimensional gas chromatography’, ACS Omega, 6(47), pp. 31667-31676. doi: 10.1021/acsomega.1c04196. Oswald, I.W.H. et al. (2023) ‘Minor, nonterpenoid volatile compounds drive the aroma differences of exotic cannabis’, ACS Omega, 8(36), pp. 39203-39216. Russo, E.B. (2011) ‘Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects’, British Journal of Pharmacology, 163(7), pp. 1344-1364. doi: 10.1111/j.1476-5381.2011.01238.x. National Center for Biotechnology Information (2025) PubChem Compound Database. Bethesda: U.S. National Library of Medicine. Available at: https://pubchem.ncbi.nlm.nih.gov (Accessed: 3 August 2026).

Sulphur Compounds

Sulphur Compounds in Cannabis: The Skunk Molecule Explained | PatientsCann UK Skip to the compound library PatientsCann UK  ·  Education Understanding Sulphur Compounds Cannabinoids and terpenes get all the attention. But a third group of molecules, the volatile sulphur compounds, is the real reason cannabis can smell so skunky, so gassy, or so surprisingly tropical. Here is what they are, and why they matter to patients. 9 compounds The skunk molecule explained Live chemical structures The garlic connection On this page What they are Aroma families The garlic link Freshness & curing Why tests miss them The full family Questions References What are sulphur compounds? Sulphur compounds, or volatile sulphur compounds, are a group of smelly molecules the cannabis plant makes in tiny amounts. Volatile just means they float easily into the air, which is why you smell them the moment you open a jar. They were only pinned down recently. In 2021 a team of scientists found a whole new family of them in cannabis, and showed that one, called 3-methyl-2-butene-1-thiol, is the main reason strong cannabis smells skunky. What makes them special is their power. Where terpenes are measured in whole percentages, these sulphur compounds work at a few parts per billion. A trace is all it takes to change how a whole plant smells. The third pillar of aroma Think of cannabis smell as a three-legged stool. Cannabinoids like THC and CBD do the medical work. Terpenes bring the citrus, pine and floral notes. Sulphur compounds add the skunk, the gas and the tropical punch. Together they give every cultivar its signature. Explore the other two in our cannabinoids and terpenes guides. Interactive The Three Aroma Families Cannabis sulphur compounds fall into a few groups by how they smell: pungent skunk and diesel, savoury garlic, bright tropical fruit, and the milder everyday smells found in food. Pick any compound below to see its family, its smell, and how powerful it is. The hopeful part The Garlic Connection Here is the exciting bit. Many of the sulphur compounds in cannabis are built almost exactly like the ones in garlic. The only real difference is a small chemical part: cannabis uses a “prenyl” group where garlic uses an “allyl” group. Cannabis Prenyl thiol the skunk molecule nearly the same shape Garlic Allyl thiol a garlic molecule Why it matters: Garlic’s sulphur compounds have been studied for years for possible benefits to the heart and blood vessels. Because cannabis makes such close copies, scientists have raised a hopeful question: might the cannabis versions one day show benefits of their own? Hopeful research, not proven Interactive Freshness: Why Timing Changes the Smell Sulphur compounds are delicate. They build up late in the plant’s life, peak at just the right moment, then fade away. This is why the same flower can smell powerful one week and flat the next. Tap each stage to follow the journey. What this means for you: if aroma matters to you, fresher is usually better. Keep cannabis in an airtight container, somewhere cool and dark, and it will hold its smell for longer. Illustration based on greenhouse monitoring by Oswald and colleagues (2021). The exact rise and fall differ from plant to plant. Good to know Why Your Lab Report Misses Them If sulphur compounds matter so much to smell, why are they almost never listed on a product’s lab report? The answer is that they are genuinely hard to catch. 1 They hide in tiny amounts Sulphur compounds appear at parts per billion, or even parts per trillion. That is thousands of times less than a typical terpene, so they are very easy to walk straight past. 2 Normal tests are not tuned for them The usual lab equipment is set up to measure cannabinoids and terpenes. It is not designed to spot faint sulphur smells, so it often does not report them at all. 3 It takes special kit The 2021 discovery needed a powerful method called two-dimensional gas chromatography with sulphur detection. Very few routine labs run it. The takeaway: a lab report (sometimes called a COA) tells you about cannabinoids and often terpenes, but rarely these sulphur compounds. If they are missing from the paperwork, it does not mean they are missing from the jar. Often, your own nose is the better guide. Full library The Sulphur Compound Family Select any card to open the full profile, with its accurate chemical structure, how it smells, what the research says, and where else you meet it in daily life. Use the filters to narrow the list by aroma family. Filter: All Skunk & diesel Garlic Tropical Everyday Questions Sulphur Compounds: Your Questions Answered What makes cannabis smell skunky? The main reason is a volatile sulphur compound called 3-methyl-2-butene-1-thiol, sometimes called prenylthiol. In 2021 scientists showed that the more of it a plant makes, the skunkier it smells. It is powerful even at a few parts per billion, so a trace goes a long way. Are sulphur compounds the same as terpenes? No. Terpenes give the citrus, pine and floral notes and are measured in whole percentages. Sulphur compounds contain a sulphur atom, work at far lower amounts, and add the skunk, gas and tropical smells that terpenes alone cannot explain. You can read about the aroma side in our terpenes guide. Why do cannabis sulphur compounds get compared to garlic? Cannabis makes sulphur compounds built much like the ones in garlic and onion. Garlic’s versions have been studied for possible heart and blood-vessel benefits, which is why researchers are hopeful about the cannabis ones. It is important to be clear that this is an early idea, not a proven health benefit. Does fresh cannabis smell stronger? Usually yes. Sulphur compounds rise in the last weeks of flowering and peak during curing, then fade once a jar is opened and over months of storage. Storing your cannabis airtight, cool and dark helps keep the aroma for longer. Why are sulphur compounds not on my

THC COOH

THC-COOH (11-Nor-9-carboxy-THC): The Inactive Metabolite | PatientsCann UK Skip to main content Back to Cannabinoids Guide COOH THC-COOH 11-nor-9-carboxy-THC, THC-11-oic acid, carboxy-THC pronounced: ih-LEV-uhn nor nine kar-BOK-see T-H-C The inactive metabolite your body makes last, as it packs THC away for removal. It is what most drug tests look for. Metabolite (body-made)Formula: C21H28O4Intoxicating: No TypeMetabolite FormulaC21H28O4 IntoxicatingNo Key focusDrug tests 11-Nor-9-carboxy-delta-9-THC · 344.4 g/mol The molecule Chemical structure This is the accurate skeletal structure of THC-COOH, drawn from PubChem data. Your body has oxidised the end of the THC molecule all the way to a carboxylic acid (the -COOH group). This switches its activity off. Its formula is C21H28O4 and it weighs 344.4 g/mol. InactiveDrug-test markerStored in fatLast step About What is THC-COOH? THC-COOH is the main inactive product your body makes as it clears THC. Its full name is 11-nor-9-carboxy-delta-9-tetrahydrocannabinol, which is a mouthful, so almost everyone calls it THC-COOH or carboxy-THC. It is made in two steps. First your liver turns THC into the strong, active 11-hydroxy-THC. Then it oxidises that into THC-COOH, which no longer causes a high. This is your body switching the medicine off and getting ready to remove it. In the body How THC-COOH Works THC-COOH does not switch on the CB1 receptor, so it produces no high at all. In that sense it does not really “work” in the way THC does. Its job is to be removed. To do that, your body attaches a sugar (glucuronic acid) to it. This makes it dissolve in water so your kidneys and gut can flush it out. Some laboratory studies have looked at mild anti-inflammatory effects, but it is not used as a medicine. Receptor snapshot Where THC-COOH Acts The endocannabinoid system has two main receptors. Here is how strongly THC-COOH acts on each. CB1Brain & nervous systemNone Does not switch on CB1. This is why it is inactive and causes no high. CB2Immune system & bodyNone Little to no direct action at CB2 either. Beyond CB1 and CB2: THC-COOH is the body’s inactive “exhaust”. It is the compound most urine drug tests are designed to find, because it lingers far longer than THC. In the body How THC-COOH is Made THC-COOH is the final active-to-inactive step. THC becomes 11-hydroxy-THC, which is then oxidised into THC-COOH. A sugar is attached to make it water-soluble, and it is then excreted, mostly in faeces (about 65 to 80 percent) and urine (about 20 to 35 percent). Because it dissolves into body fat, it is released slowly, which is why it can be found long after the last dose. Pathway11-OH-THC→THC-COOH→ sugar →excreted Good to know Safety and Drug Testing THC-COOH is not intoxicating and does not impair you. But because it lingers in fat, it can show up on a urine drug test for days after occasional use, and for several weeks in people who use cannabis heavily or who have more body fat. Being a legal UK patient does not stop the test from being positive. If you drive for work or face workplace testing, tell your prescriber and keep your prescription paperwork to hand. Questions THC-COOH: Common Questions Does THC-COOH get you high? No. THC-COOH is inactive. It does not switch on the CB1 receptor, so it produces no high. It is simply the form your body makes to pack THC away and remove it. Why does cannabis stay in your system so long? THC-COOH dissolves into body fat and is released slowly over time. Most urine drug tests look for THC-COOH, not THC itself, which is why cannabis can be detected for days after occasional use and for several weeks after heavy, regular use. Previous11-Hydroxy-THC NextDelta-9-THC Back to full Cannabinoids Guide Important: This page is for education only. It is not medical advice. Cannabinoid research is still developing, and many studies have been done in cells or animals rather than people. Always speak to your prescriber before changing your treatment. PatientsCann UK does not recommend any specific cannabis product. References Huestis, M.A. (2007) ‘Human cannabinoid pharmacokinetics’, Chemistry & Biodiversity, 4(8), pp. 1770-1804. doi: 10.1002/cbdv.200790152. Watanabe, K. et al. (2007) ‘Cytochrome P450 enzymes involved in the metabolism of tetrahydrocannabinols and cannabinol by human hepatic microsomes’, Life Sciences, 80(15), pp. 1415-1419. doi: 10.1016/j.lfs.2006.12.032. Grotenhermen, F. (2003) ‘Pharmacokinetics and pharmacodynamics of cannabinoids’, Clinical Pharmacokinetics, 42(4), pp. 327-360. doi: 10.2165/00003088-200342040-00003. National Center for Biotechnology Information (2025) PubChem Compound Summary for CID 65079, 11-Nor-9-carboxy-Delta9-THC. Bethesda: U.S. National Library of Medicine. Available at: https://pubchem.ncbi.nlm.nih.gov (Accessed: 3 August 2026).

11 Hydroxy THC

11-Hydroxy-THC: The Metabolite Behind Edibles | PatientsCann UK Skip to main content Back to Cannabinoids Guide 11-OH 11-Hydroxy-THC 11-OH-THC, 11-hydroxy-delta-9-THC pronounced: ih-LEV-uhn hy-DROK-see tet-ruh-hy-droh-kuh-NAB-ih-nol The stronger metabolite your liver makes from THC. It is the reason eaten cannabis can feel so much more intense. Metabolite (body-made)Formula: C21H30O3Intoxicating: Yes, stronger TypeMetabolite FormulaC21H30O3 IntoxicatingYes Key focusEdibles 11-Hydroxy-delta-9-THC · 330.5 g/mol The molecule Chemical structure This is the accurate skeletal structure of 11-hydroxy-THC, drawn from PubChem data. It is almost identical to THC, but your liver has added an oxygen and hydrogen (an -OH group) at one end. That tiny change makes it stronger. Its formula is C21H30O3 and it weighs 330.5 g/mol. Stronger than THCLong-lastingReaches brain fastEdible effects About What is 11-Hydroxy-THC? 11-Hydroxy-THC is a metabolite. That means it is not made by the plant. Instead, your own body makes it in the liver when it starts to break THC down. Its full name is 11-hydroxy-delta-9-tetrahydrocannabinol, usually shortened to 11-OH-THC. Here is the surprising part: it is stronger than THC itself. Research suggests it is somewhere between 1.5 and 7 times more active at the CB1 receptor, and it slips into the brain more easily. So the molecule your body makes can pack more of a punch than the one you started with. In the body How 11-Hydroxy-THC Works Like THC, 11-hydroxy-THC works by switching on the CB1 receptor in the brain and nerves. But because it fits that receptor even better and crosses into the brain more readily, the effects can feel stronger and last longer. This is the hidden reason an edible can feel so different from a vape. When cannabis is eaten, a large share of the THC is turned into 11-hydroxy-THC before it ever reaches the rest of your body. When it is inhaled, far less is made. Receptor snapshot Where 11-Hydroxy-THC Acts The endocannabinoid system has two main receptors. Here is how strongly 11-hydroxy-THC acts on each. CB1Brain & nervous systemVery strong Fits CB1 even better than THC. This is what makes it more potent, and why eaten cannabis can feel so intense. CB2Immune system & bodyPartial Also acts on CB2 in the immune system, much like THC does. Why it matters: after an edible, blood levels of 11-hydroxy-THC can be as high as, or higher than, THC itself. After inhaling, there is far less. This is the main reason the two routes feel so different. In the body How 11-Hydroxy-THC is Made When you swallow cannabis, it travels to the liver before reaching the rest of your body. This is called first-pass metabolism. A liver enzyme called CYP2C9 adds an oxygen to THC, turning it into 11-hydroxy-THC. Your body then oxidises it again into the inactive THC-COOH, which is later flushed out. How fast all of this happens differs a lot from person to person. PathwayTHC→ liver →11-OH-THC→THC-COOH Good to know Safety and Side Effects Because 11-hydroxy-THC is stronger, edibles can catch people out. The onset is slow, often 30 minutes to 2 hours, so it is easy to think a dose “isn’t working” and take more. When both doses land together, the effect can be overwhelming, with anxiety, a racing heart or feeling faint. The golden rule with edibles is to start low, go slow, and wait at least 2 hours before considering any more. It affects driving. Always follow your prescriber’s advice. Questions 11-Hydroxy-THC: Common Questions Why do edibles feel stronger than smoking? When you eat cannabis, your liver changes most of the THC into 11-hydroxy-THC before it reaches the rest of your body. This metabolite is stronger than THC and reaches the brain more easily, so an eaten dose can feel much more intense and last longer than an inhaled one. Is 11-hydroxy-THC found in the cannabis plant? No. 11-hydroxy-THC is not made by the plant. It is a metabolite, which means your own body makes it in the liver while breaking down THC, mostly using an enzyme called CYP2C9. PreviousCBGA NextTHC-COOH Back to full Cannabinoids Guide Important: This page is for education only. It is not medical advice. Cannabinoid research is still developing, and many studies have been done in cells or animals rather than people. Always speak to your prescriber before changing your treatment. PatientsCann UK does not recommend any specific cannabis product. References Huestis, M.A. (2007) ‘Human cannabinoid pharmacokinetics’, Chemistry & Biodiversity, 4(8), pp. 1770-1804. doi: 10.1002/cbdv.200790152. Grotenhermen, F. (2003) ‘Pharmacokinetics and pharmacodynamics of cannabinoids’, Clinical Pharmacokinetics, 42(4), pp. 327-360. doi: 10.2165/00003088-200342040-00003. Sachse-Seeboth, C. et al. (2009) ‘Interindividual variation in the pharmacokinetics of delta-9-tetrahydrocannabinol as related to genetic polymorphisms in CYP2C9’, Clinical Pharmacology & Therapeutics, 85(3), pp. 273-276. doi: 10.1038/clpt.2008.213. National Center for Biotechnology Information (2025) PubChem Compound Summary for CID 37482, 11-Hydroxy-Delta9-THC. Bethesda: U.S. National Library of Medicine. Available at: https://pubchem.ncbi.nlm.nih.gov (Accessed: 3 August 2026).

Open Letter Reddit

Open Letter on Patient Access, Welfare and Moderation Transparency | PatientsCann UK® Skip to content Open letter Patient welfare Public statement Open letter: why free patient help is being blocked on r/ukmedicalcannabis PatientsCann UK CIC is a non-profit. Our help is free, and it always will be. Yet for around four years we have watched our free patient resources be filtered, removed and then banned on the r/ukmedicalcannabis subreddit. This is our open letter. It sets out what happened, the reasons we were given, our honest answer to each one, and where you can always find us. PatientsCann UK CIC Open letter 30 July 2026 Read our free resources On this page The core issue Timeline Our directors Reasons and our answer Why it harms patients Our commitment Find us References About this letter This is an open statement of our own experience, shared to inform patients and to invite fair dialogue. It is not legal advice. In the screenshots below, moderator names have been removed, and the only accounts shown are our own team’s. The screenshots also show our former name and website, The Sanskara Platform; we now operate as PatientsCann UK CIC. Who we are PatientsCann UK CIC is a registered Community Interest Company. A CIC is a non-profit set up to serve the community, not to make money for owners. We exist to give UK medical cannabis patients free, honest information, legal guidance and support. We take no payment from patients for any of it. We are writing this letter because free, non-profit patient resources, ours and those we are linked to, keep being filtered, removed and banned on one of the busiest patient forums in the country: the r/ukmedicalcannabis subreddit. We have asked, appealed, and offered to follow every rule. Time and again we have been met with silence. Why this matters Free, not for profit Every guide, legal framework and toolkit we make is free. We take no money from patients, ever. Removed and banned Our links and crossposts were filtered, our posts held for approval, and then we were permanently banned. Appeals ignored Our requests, formal appeals and offers to talk have gone unanswered for years. The core issue Gatekeeping essential patient information UK medical cannabis is new, complex, and changing fast. Patients lean on each other, and on trusted independent guidance, to stay safe and to stay legal. When the first forum a worried patient finds removes free, non-commercial education, patients are the ones who lose out. Over the past few years we have found that resources produced by, or linked to, PatientsCann UK have been filtered and removed from r/ukmedicalcannabis. This has even included content where we were not the only author, but were simply named as a contributor or a source. At the time we operated under our former name, The Sanskara Platform, and links to that free resource site, along with crossposts linked to our work, were blocked. The pattern we have seen: free help is treated as advertising, links are quietly filtered, appeals are ignored, and the door is closed with no clear right to reply. What we have experienced A documented timeline Around 4 years agoOur links removed, our crossposts blocked Links to our free resource site were being automatically removed, and crossposts from our patient committee subreddit were disabled. When we asked why, the moderators told us the material was being treated as advertising, because our website “appears to be built by and partnered with companies and consultancies in the medical cannabis sector.” Our answer at the time was simple: the site exists to give patients resources and education, and it makes no money from those links. Moderation reply confirming our links and crossposts were being automatically filtered as “advertising”, and our response explaining the resources are free. Around 4 years agoA patient resource taken down A post explaining how to verify a patient was removed under the “no advertising” rule. In the same message, the moderator accepted that the post “does contain a patient resource”, but removed it anyway. A free patient resource removed under the “no advertising” rule, even though the moderator accepted it was a genuine patient resource. Around 4 years agoPosting rights limited to approval only After a month-long ban was lifted, we were told we were not banned. In practice, every post and comment we made would be held back and would only appear if a moderator approved it first. Told we were “not banned”, but that every post and comment would have to wait for a moderator to approve it. Around 3 years agoWe tried again, in good faith We reached out again, calmly, hoping to reach “a mature conclusion” about the block on our resources. We explained that patients ask the same questions every day, questions our free guides already answer, and asked to talk it through so we could move forward together. Our good-faith request to reopen the conversation and find a fair way forward for the community. Around 3 years agoA permanent ban, and a question turned back on us We were then permanently banned from taking part in r/ukmedicalcannabis. When we asked for a clear reason, and suggested an independent review of the decision, the reply did not answer the point. Instead it turned the question back on us, saying that if anything needed investigating, it was our “backing and investors.” The permanent ban notice, and the exchange that followed when we asked for reasons and an independent review. This year, MarchA fresh request for review, met with silence Most recently, in March, we sent a calm, respectful request to revisit the ban. We explained that we were never given a clear or definitive reason, and that we simply wanted the chance to put it right. As with our earlier appeals, we received no meaningful reply. Our most recent request for review, sent in good faith and, once again, left unanswered. Not one account This reached others. The messages above are from our Managing Director. But