Amyl Nitrite (Nasal) (Monograph)

Drug class: Nitrates and Nitrites

Medically reviewed by Drugs.com on Jun 10, 2024. Written by ASHP.

Introduction

Amyl nitrite, an organic nitrite, is a vasodilating agent.

Uses for Amyl Nitrite (Nasal)

Angina

Amyl nitrite shares the actions of the other nitrates and nitrites and has been used for acute relief of angina pectoris; however, the drug is seldom, if ever, used for angina pectoris because it is expensive, inconvenient, has a high incidence of adverse effects (e.g., headache, orthostatic symptoms, tachycardia), and has an unpleasant odor.

Cyanide Poisoning

Amyl nitrite is used as an adjunct in the treatment of cyanide poisoning. Nitrite ions react with hemoglobin to form methemoglobin which unites with cyanide to form cyanmethemoglobin.

Diagnostic Aid for Heart Murmurs

Amyl nitrite also has been used to produce changes in the intensity of heart murmurs^{† [off-label]}. Murmurs resulting from stenosis of any of the 4 cardiac valves or from idiopathic hypertrophic subaortic stenosis will become louder after amyl nitrite adminis ration. Murmurs resulting from aortic or mitral regurgitation usually decrease in intensity.

Misuse and Abuse

Amyl nitrite and other volatile nitrites (“poppers”) have been used illicitly to enhance sexual pleasure. Some initial studies suggested that use of volatile nitrites, including amyl nitrite, may be one of numerous risk factors associated with the development of acquired immunodeficiency syndrome (AIDS) and Kaposi’s sarcoma in male homosexuals;^{100 101} however, more recent epidemiologic studies, while confirming the frequent use of volatile nitrites by homosexual men, have not found nitrite use to be a significant risk factor,^{102 103 104} and some data suggest that the initial attribution of risk may have been related to an association between nitrite use and certain behaviors and practices associated with enhanced transmission of the human innumodeficiency virus (HIV).¹⁰⁴

Misuse and abuse of amyl nitrite and other inhaled volatile nitrites may be associated with potentially life-threatening hypotension and/or hemodynamic compromise when combined with selective phosphodiesterase (PDE) inhibitors, which are used to increase the duration and intensity of erection.

Amyl Nitrite (Nasal) Dosage and Administration

Administration

Amyl nitrite is administered by nasal inhalation. The patient should be sitting during and immediately after inhaling amyl nitrite. The ampul, wrapped in a woven absorbent covering, is crushed between the fingers and held to the nostrils for inhalation.

Dosage

Dosage of amyl nitrite must be adjusted according to the patient’s requirements and response.

Angina

For acute relief of angina pectoris, the usual dosage of amyl nitrite is 0.18–0.3 mL as required.

Cyanide Poisoning

For the treatment of cyanide poisoning in adults and children, a 0.3-mL ampul of amyl nitrite is crushed every minute and the vapor is inhaled for 15–30 seconds until an IV sodium nitrite infusion is available. In adults, 300 mg (10 mL of a 3% solution) of sodium nitrite is infused IV at the rate of 2.5–5 mL/minute and immediately followed by 12.5 g (50 mL of a 25% solution) of sodium thiosulfate IV over a period of about 10 minutes. Dosage of sodium nitrite in children must be carefully adjusted to avoid the formation of excessive methemoglobin. In children, the dose of sodium nitrite is 180–240 mg/m² (6–8 mL/m² of a 3% solution) or 6 mg/kg (0.2 mL/kg of a 3% solution); dosage in children should not exceed 300 mg. IV sodium thiosulfate should be administered immediately after sodium nitrite; one clinician recommends that children receive 5 mL of a 25% sodium thiosulfate solution for every 1 mL of 3% sodium nitrite solution. If signs of cyanide poisoning reappear in adults and children, 50% of the initial doses of both sodium nitrite and sodium thiosulfate should be given.

Diagnostic Aid for Heart Murmurs

To produce changes in the intensity of heart murmurs^{† [off-label]}, amyl nitrite is inhaled until reflex tachycardia begins and then is discontinued immediately.

Amyl Nitrite (Nasal) Pharmacokinetics

Following nasal inhalation of amyl nitrite, angina pectoris is relieved within 30 seconds and the duration of action is about 3–5 minutes. Following nasal inhalation in patients with or without coronary artery disease, substantial hemodynamic effects such as increased heart rate and decreased brachial artery and left ventricular end-diastolic pressures occur within 30 seconds and persist at least 5 minutes.

Chemistry and Stability

Chemistry

Amyl nitrite, an organic nitrite, occurs as a clear yellowish, volatile, flammable liquid having a peculiar, ethereal, fruity odor and pungent aromatic taste and is practically insoluble in water and miscible with alcohol.

Stability

Amyl nitrite vapor forms an explosive mixture in air or oxygen at room temperature and may explode if ignited. Amyl nitrite inhalant should be packaged in unit-dose containers, wrapped loosely in gauze or other suitable material, and stored at 2–15°C. A stabilizer, such as diphenylamine or epoxolol, is added to the commercially available products. The drug should be protected from light.

Additional Information

The American Society of Health-System Pharmacists, Inc. represents that the information provided in the accompanying monograph was formulated with a reasonable standard of care, and in conformity with professional standards in the field. Readers are advised that decisions regarding use of drugs are complex medical decisions requiring the independent, informed decision of an appropriate health care professional, and that the information contained in the monograph is provided for informational purposes only. The manufacturer’s labeling should be consulted for more detailed information. The American Society of Health-System Pharmacists, Inc. does not endorse or recommend the use of any drug. The information contained in the monograph is not a substitute for medical care.

Preparations

Excipients in commercially available drug preparations may have clinically important effects in some individuals; consult specific product labeling for details.

Please refer to the ASHP Drug Shortages Resource Center for information on shortages of one or more of these preparations.

* available from one or more manufacturer, distributor, and/or repackager by generic (nonproprietary) name

Medical Disclaimer