A letter dated 16 March 2016 from the government’s drug advisers told the Home Office minister Karen Bradley that poppers did not fall inside the new Psychoactive Substances Act. Earlier that year, ministers had indicated that they would be banned. The explanation is a technical one, and it is easier to follow than it sounds.
The one clause that decided it
Section 2 of the Act sets the test. A substance counts as psychoactive if it can produce a psychoactive effect, and the Act defines that effect as a change in someone’s mental functioning or emotional state caused by stimulating or depressing the central nervous system. When someone asks are poppers legal in the uk, the honest answer starts with that definition. Everything else follows from how it is read.
Read the clause as a two-step test. First ask whether the substance acts on the central nervous system. Then ask whether that action changes mental functioning or emotional state. The ACMD stopped at the first step because it judged that poppers do not act on the central nervous system directly.
The Advisory Council on the Misuse of Drugs (ACMD) took the view that a psychoactive substance acts directly on the brain. Poppers, it said, open blood vessels and relax smooth muscle, and the rush people report is the brain registering extra blood flow. Because the blood vessels involved lie outside the blood-brain barrier, their effects count as peripheral.
That is a narrow, mechanical reading, and it is worth noticing what it does not say. It does not say poppers are mild, and it does not say the effect is imaginary. It says only that the Act’s test as written asks where the effect starts. Reading the Act this way also explains why different writers can describe the same facts as a ban or as an exemption.
The three options the ACMD weighed
Picture two friends arguing about whether poppers were banned in 2016. One remembers ministers saying they would be, and the other remembers a news report saying they were not. Both are describing a real moment, and the gap between those moments is the story.
The ACMD considered three outcomes. Poppers could be caught and controlled, they could be psychoactive but placed on the Act’s list of exemptions, or they could fall outside the definition altogether. It chose the third and concluded that no exemption was needed.
The government agreed with that reading, according to a minister’s letter of 22 March 2016 quoted by the barrister Rudi Fortson. That choice has a practical consequence. Poppers are not named in the Act’s list of exempt substances, and that silence is easy to misread as either a ban or an approval.
Treating that silence as a formal exemption is the common mistake. An exemption means a substance is listed in Schedule 1. In 2016 the ACMD’s view was that poppers did not need listing because the Act did not reach them in the first place.
The same ACMD advice describes how the products are sold. In 2016 it said the legally available form was isopropyl nitrite, sold in small sealed bottles with labels describing it as an air freshener or a video head cleaner. That detail is from 2016, and the 2024 report says manufacturers now generally use other compounds, so old descriptions of the products may be out of date.
What escaping the Act did and did not change
The reading was not the last word. A 2018 Court of Appeal ruling confirmed that a substance with only an indirect psychoactive effect can still be caught by the Act, according to the Home Secretary’s letter to the ACMD in 2020. That letter described the position on supply as uncertain and said the Home Secretary was minded to exempt poppers explicitly, and in 2024 the ACMD recommended adding alkyl nitrites to Schedule 1.
Escaping the Act also did not make poppers harmless. The ACMD’s 2016 advice warns that poppers could lead to methaemoglobinaemia, which reduces the blood’s ability to carry oxygen and can be life-threatening, and it notes reports of eye damage. It also says that taking poppers with other vasodilators such as sildenafil is potentially life-threatening. It further warns that poppers are very flammable and can cause chemical burns on the skin.
Conclusion
If you are writing about poppers, or deciding what to believe, test every claim against the definition in section 2 and the date of the source. If your case is complicated, a solicitor can tell you how the law applies to you, and anyone considering use should speak to a doctor or pharmacist first. Then open Schedule 1 of the Act on legislation.gov.uk and see whether alkyl nitrites appear there today.
