Results were different for two of the samples of Jungle Juice Plus. One was a mixture of compounds tentatively identified as having amyl, 2-methyl butyl and isobutyl structure, but the nitrite functional group was absent as confirmed by Raman spectroscopy.
The other sample of Jungle Juice Plus contained nitrite and was identified as a mixture of amyl nitrite, 2-methyl butyl nitrite and the corresponding alcohols.
Three patients said they had used poppers for at least 20 years but only noticed symptoms when they switched brands. One of them noticed the symptoms after a binge of Jungle Juice containing isopropyl nitrite in which he inhaled about every 5 minutes for a half hour.
Though isobutyl alcohol is not illegal in the UK, “its detection is concerning, given that isobutyl nitrite is a banned carcinogen and a potential source of isobutyl alcohol”, Dr Rewbury and her colleagues wrote.
Another patient reported using other brands without visual symptoms, then switching to Berlin XXX, which contains isopropyl nitrite. A third patient did not experience any visual side effects when he used isobutyl nitrites in the 1980s, but after a binge in which he inhaled Amsterdam poppers about every 5-10 minutes for 5 hours, he developed a central scotoma.
Symptoms and abnormalities mostly improved over time. After abstaining from poppers for 6 months after diagnosis, six patients were asymptomatic within a few months, with improvements in measured visual acuity. Abnormalities on optical coherence tomography (OCT) also improved gradually but were still present in some cases after symptoms resolved.
One patient continued to use poppers, but switched to another brand. His symptoms continued for five months but resolved after a year. Another patient experienced an improvement when he stopped using poppers, but lost visual acuity and had changes visible on OCT when he started again.
“The cases presented here suggest that certain brands of poppers may be more toxic to the retina than others, with users anecdotally identifying a link between specific brands and the onset of their visual symptoms,” Dr Rewbury and colleagues concluded.
“Chemical analysis of the products tested suggests that isopropyl nitrite is responsible for poppers' maculopathy, although the mechanism of this is unknown.”