Seizures and severe methaemoglobinaemia following accidental ingestion of amyl nitrite.

We present a case of a man in his late 40s presenting with generalised tonic-clonic seizures and profound methaemoglobinaemia shortly after inadvertent ingestion of amyl nitrite. Arterial blood gas analysis demonstrated methaemoglobin levels exceeding the upper detection threshold of our analyser, accompanied with profound cyanosis despite apparent oxygen saturations of 94%. Prompt administration of intravenous methylene blue led to a rapid and complete recovery. This case highlights the importance of swift recognition and treatment of methaemoglobinaemia particularly when the precipitating factor may be unknown at the time of presentation. This case also demonstrates the potential limitations of bedside blood gas analysers in diagnosis.

Association Between Nitrite and Nitrate Intake and Risk of Gastric Cancer: A Systematic Review and Meta-Analysis.

BACKGROUND Studies have shown inconsistent associations of nitrite and nitrate intake with the risk of gastric cancer or its associated mortality. We performed a meta-analysis of observational studies to evaluate the correlation of nitrite and nitrate intake with the risk of gastric cancer. MATERIAL AND METHODS We searched for studies reporting effect estimates and 95% confidence intervals (CIs) of gastric cancer in PubMed, EMBASE, and the Cochrane Library through November 2018. The summary results of the included studies were pooled using a random-effects model. RESULTS Eighteen case-control and 6 prospective cohort studies recruiting 800 321 participants were included in this study. The summary results indicated that the highest (odds ratio [OR], 1.27; 95%CI, 1.03-1.55; P=0.022) or moderate (OR: 1.12; 95%CI, 1.01-1.26; P=0.037) nitrite intake were associated with a higher risk of gastric cancer. However, we noted that high (OR, 0.81; 95%CI, 0.68-0.97; P=0.021) or moderate (OR, 0.86; 95%CI, 0.75-0.99; P=0.036) nitrate intakes were associated with a reduced risk of gastric cancer. These associations differed when stratified by publication year, study design, country, the percentage of male participants, assessment of exposure, adjusted model, and study quality. CONCLUSIONS High or moderate nitrite intake was associated with higher risk of gastric cancer, whereas high or moderate nitrate intake was correlated with lower risk of gastric cancer.

A Study of the Longitudinal Patterns of Stimulant and Amyl Nitrite Use and Sexual Behavior Pre- and Post-HIV Seroconversion Among MSM.

The use of stimulant drugs alone or in combination with amyl nitrites (stimulant/nitrites) has been associated with higher rates of risky sexual behavior and predictive of HIV infection among men who have sex with men. However, the temporal pattern of stimulant/nitrite use pre- and post-seroconversion has not been well established. This study assessed changes in stimulant/nitrite use and risky sexual behavior among seroconverting MSM over time. Data were collected in the Baltimore-Washington, DC; Pittsburgh; Chicago; and Los Angeles sites of the Multicenter AIDS Cohort Study (MACS), a longitudinal study of the natural history of HIV infection among MSM. We used propensity scores to select 1044 MSM from 7087 MACS participants composed of 348 seroconverting, 348 seronegative, and 348 seroprevalent participants matched on demographics, recruitment cohort, and study visits. We centered up to four-years of semi-annual data around the seroconversion visit of the seroconverting case within each matched group of participants. Mixed effects regressions estimated the effects of serostatus, recruitment cohort, and time on self-reported stimulant/nitrite use, numbers of male intercourse partners, and numbers of unprotected receptive anal intercourse (URAI) partners. Covariates included demographics, binge drinking, and marijuana use. Seroconverters had the highest odds of stimulant/inhaled nitrite use (AOR 10.3, CI 4.8-22.0), incident rates of intercourse (IRR 1.6, CI 1.3-2.1), and URAI partners (IRR 5.1, CI 3.5-7.3). All participants decreased drug use and sexual risk behavior over time. However, the decreases were largest for seroconverters who nevertheless maintained the highest rates of stimulant/nitrite use and sexual risk. Cohort-related effects were associated with sharp reductions in stimulant/nitrite use and URAI in the early 1990s that rebounded considerably within the first decade of the 2000s. Although all participants decreased risky sexual behavior and stimulant and/or nitrite use over time, seroconverters had the largest decreases. There was no evidence for abrupt or substantial increases in drug use or risky sex post-seroconversion. However, there was substantial variation at the individual level, with the factors underlying this variation not well understood and worth further study. Moreover, stimulant/nitrite use and risky sexual behavior appear to have been strongly influenced by contextual historical and socio-cultural effects. The manner in which contextual factors influence individual behavior is also not well understood and also warrants further study.

[Case report - a dangerous intoxication after ingestion of alkyl nitrite ("poppers")]. / Kasuistik - Schwere Intoxikation nach oraler Einnahme von Alkylnitrit ("Poppers").

This case report describes the inadvertent poisoning of a young man with "poppers" after having ingested an unknown amout of the drug. "Poppers" (alkyl nitrite) were made famous in the 1960s as a party drug, and during certain sexual practices, and are still in use today. The drug's inhalation leads to a short-lived rush, vasodilation and relaxtion of smooth muscles. An accidental ingestion can lead to a significant build-up of methemoglobin with dire consequences. The therapy consists of the intravenous administration of methylene blue.

'Popper'-induced vision loss.

Amyl nitrite 'poppers' are recreational drugs, which are a potent source of nitric oxide. The use of 'poppers' can cause psychoactive stimulation, reduced blood pressure, tachycardia and involuntary muscle relaxation. Their use is becoming increasingly common around the world, including approximately 60% of Australia's male homosexual community. We report the first case of 'popper'-induced vision loss in Australasia.

Didactic image poppers maculopathy.

We describe a case of toxic maculopathy caused by unique inhalation of poppers. This maculopathy has spontaneously resolved.

Foveal damage in habitual poppers users.

OBJECTIVE: To describe foveal damage in habitual use of poppers, a popular recreational drug. METHODS: Retrospective observational case series. Six patients with bilateral vision loss after chronic popper inhalation were seen in 4 university-based ophthalmology departments. Symptoms, medical history, ophthalmic examination, and functional and morphological tests are described. RESULTS: All patients experienced progressive bilateral vision loss, with central photopsia in 2 cases. Initial visual acuities ranged from 20/50 to 20/25. In all patients, a bilateral yellow foveal spot was present that, by optical coherence tomography, was associated with disruption of the outer segments of foveal cones. Functional and anatomical damage was restricted to the fovea. The poppers involved were identified as isopropyl nitrite in 3 cases. Four patients showed anatomical and/or functional improvement over several months after discontinuing popper inhalation. CONCLUSIONS: Repeated inhalation of poppers may be associated with prolonged bilateral vision loss due to the disruption of foveal cone outer segments. Retinal damage may progressively improve following drug discontinuation.

Does amyl nitrite have a role in the management of pre-hospital mass casualty cyanide poisoning?

CONTEXT: Amyl nitrite has been recommended as a cyanide antidote for several decades. Its antidotal properties were initially attributed to induction of methemoglobin and later to a nitric oxide mediated hemodynamic effect. The ease of administration and alleged rapid clinical effect would recommend its wide use in the pre-hospital management of mass casualty cyanide poisoning; yet there are concerns regarding the use of amyl nitrite for this indication. OBJECTIVE: Review the data on amyl nitrite in cyanide poisoning and evaluate its efficacy and safety in mass casualty cyanide poisoning. METHODS: A literature search utilizing PubMed, Toxnet, textbooks in toxicology and pharmacology, and the bibliographies of the articles retrieved identified 17 experimental studies and human reports on the use of amyl nitrite in cyanide poisoning, and 40 additional articles on amyl nitrite's properties and adverse effects. One paper was excluded as it was a conference abstract with limited data. MECHANISMS OF ACTION: The antidotal properties of amyl nitrite were attributed initially to induction of methemoglobinemia and later to nitric oxide mediated vasodilation. EXPERIMENTAL STUDIES: Animal studies on the use of amyl nitrite in cyanide poisoning are limited, and their results are inconsistent, which makes their extrapolation to humans questionable. HUMAN STUDIES: Clinical reports are limited in number and the part played by amyl nitrite relative to the other treatments administered (e.g. life support, sodium nitrite, and sodium thiosulfate) is unclear. ADVERSE EFFECTS: Amyl nitrite can be associated with potentially serious adverse reactions such as hypotension, syncope, excessive methemoglobinemia, and hemolysis in G6PD deficient patients. These effects are more pronounced in young children, in the elderly, and in patients with cardiac and pulmonary disorders. Dose regimen. The method of administration of amyl nitrite (breaking pearls into gauze or a handkerchief and applying it intermittently to the victim's nose and mouth for a few minutes) is not easily controlled, might result in under- or over-dosing, can prevent the caregiver from administering life support, and possibly expose him/her to amyl nitrite's adverse effects. CONCLUSIONS: Administration of amyl nitrite in mass casualty cyanide poisoning can result in unnecessary morbidity and may interfere with the proper management of the incident and the required supportive treatment and rapid evacuation. In the authors' opinion these drawbacks make the use of amyl nitrite in pre-hospital mass casualty cyanide poisoning unwarranted.

Problems in three Japanese drug users with Human Immunodeficiency Virus infection.

Numbers of individuals infected with Human Immunodeficiency Virus (HIV) are increasing in Japan. The majority of them are Men who have sex with men and a part of them take drugs as 'Sex drug' at their sexual intercourse. Especially, Amyl nitrite, Methamphetamine, 5-methoxy-N, N-diisopropyltryptamine (5-MeO-DIPT; Foxy), and 3, 4-methylenedioxy- methamphetamine (MDMA; Ecstasy) are used, and they sometimes cause the physical and mental disorders. However, the actual drug inducing troubles among Japanese HIV-infected drug users had not yet been discussed enough. In this report, we describe three cases with HIV infection; a case developed severe neuroleptic malignant syndrome (NMS) after taking 5-MeO-DIPT, a case with persistent convulsion due to multiple drug intake and a case with rhabdomyolysis due to the non-subjective methamphetamine intake. Through these cases, we raise and discuss several underlying problems associated with drug use among HIV-infected individuals.

Transient visual loss after amyl Isobutyl nitrite abuse.

PURPOSE: To report retinal alterations after Isobutyl nitrite (popper) inhalation. METHODS: Case Report. RESULTS: A 30-year-old man presented a sudden visual decrease following the use of Isobutyl nitrite (popper) while he was at a discotheque. His visual acuity (VA) was 20/50 in the right eye (RE) and 20/63 in the left eye (LE). Ophthalmoscopy revealed symmetric alteration of the foveal reflex with a small yellowish-white spot in the foveal area, much more evident in the RE. Fluorescein angiography and OCT were normal. Visual field showed a mild reduction of central differential light sensitivity. A progressive recovery was noted and at one month's follow-up VA was 20/25 in OU with very faint yellowish-white spots. CONCLUSIONS: The inhalation of drugs as "popper" may cause a visual loss by unclear mechanisms.