When fumes from these substances are inhaled, they act as potent vasodilators, producing mild euphoria, warmth, and dizziness.

[2] The term poppers stems from the "popping" sound of glass vials containing the substance when crushed to release vapour for inhalation.

Vasodilation may cause giddiness, dizziness, headache, nausea, vomiting and flushing, and may produce a sensation of heat and excitement.

[20] Swallowing poppers (rather than inhaling the vapour) may cause cyanosis, methemoglobinemia, unconsciousness, coma, and complications leading to death.

[25] Isopropyl nitrite poppers may be a cause of maculopathy (eye damage), as reported in France and the United Kingdom.

[26] Some studies have concluded that there may be increased risk for at least temporary retinal damage with habitual popper use in certain users; in a letter to the New England Journal of Medicine,[27] an ophthalmologist described four cases in which recreational users of isopropyl nitrite poppers suffered temporary changes in vision.

[34] This is different from the relatively brief exposure to isobutyl nitrite that inhaling poppers recreationally usually provides.

[46] Sir Thomas Lauder Brunton, a Scottish physician born in the year of amyl nitrite's first synthesis, documented its clinical use to treat angina pectoris in 1867 when patients experiencing chest pains would experience complete relief after inhalation.

[47] Brunton was inspired by earlier work with the same agent, performed by Arthur Gamgee and Benjamin Ward Richardson.

[47] Brunton reasoned that the angina sufferer's pain and discomfort could be reduced by administering amyl nitrite—to dilate the coronary arteries of patients, thus improving blood flow to the heart muscle.

[52][53] It was packaged and sold pharmaceutically in fragile glass ampoules wrapped in cloth sleeves which, when crushed or "popped" in the fingers, released the amyl nitrite for inhalation, hence the colloquialism poppers.

[52] In the late 1970s, Time magazine[54] and The Wall Street Journal[55] reported that popper use among gay men began as a way to enhance sexual pleasure, but "quickly spread to avant-garde heterosexuals".

[58] In June 2018, the Therapeutic Goods Administration (TGA) motioned to reschedule alkyl nitrites to be in the same category as heroin and cocaine (Schedule 9).

[60] In October 2018, the Australian Federation of AIDS Organisations (AFAO) pointed out the lack of quality evidence provided by the TGA to justify the rescheduling[61] and that use of amyl nitrites has been stable over the past decade with very little evidence of harm and has been in use by a high proportion of gay men over a long period.

A final decision was pushed back from 29 November 2018 to late January or early February 2019 for further consultation with the public.

[62] As of March 2019, two public meetings have taken place in Sydney and Melbourne with The Kirby Institute and the Australian Research Centre in Sex, Health and Society (ARCSHS).

[69] After litigation by sex shop owners, this extension was quashed by the Council of State on the grounds that the government had failed to justify such a blanket prohibition: according to the court, the risks cited, concerning rare accidents often following abnormal usage, rather justified compulsory warnings on the packaging.

[73] The Psychoactive Substances Act 2016, scheduled to be enacted 1 April 2016, was initially claimed to impose a blanket ban on the production, import and distribution of all poppers.

[76][77] In March 2016, the Advisory Council on the Misuse of Drugs stated that, because alkyl nitrites do not directly stimulate or depress the central nervous system, poppers do not fall within the scope of the Psychoactive Substances Act 2016.

There was a huge increase in the number of brands for butyl nitrites after the FDA put in the prescription requirement again in 1969.