Amyl nitrite relaxes the vascular smooth muscle, decreases arterial blood pressure, reduces left ventricular work, and decreases myocardial oxygen consumption. It is used to treat patients with cyanide toxicity and for the provocation of LVOT (latent left ventricular outflow tract) gradient during echocardiography in patients with hypertrophic cardiomyopathy. It is abused as it causes a sudden high and improves sexual performance.

Amyl Nitrite Dose in Adults

Dose as off-label use in the treatment of Cyanide toxicity:

• 0.3 mL ampule crushed into a gauze pad and placed in front of the patient’s mouth or endotracheal tube if the patient is intubated to inhale over 15 - 30 seconds.
• The dose may be repeated every minute until sodium nitrite can be administered.
• Amyl nitrite is a temporary intervention that is used in the prehospital settings, or if intravenous access is difficult, and until intravenous hydroxocobalamin or the sodium nitrite and sodium thiosulfate infusions can be administered.

Dose as off-label use in the treatment of Pharmacologic provocation of LVOT (latent left ventricular outflow tract) gradient in hypertrophic cardiomyopathy:

• 3 - 4 deep inhalations from one crushed ampule over a 10 - 15 second period
• The use of physiologic testing like Valsalva maneuver and treadmill testing with Doppler echocardiography are preferred over amyl nitrite.

Amyl Nitrite Dose in Childrens

Dose in the treatment of Cyanide toxicity:

• 0.3 mL ampule crushed into a gauze pad and placed in front of the patient’s mouth or endotracheal tube if the patient is intubated to inhale over 15 - 30 seconds
• The dose may be repeated until sodium nitrite can be administered.
• Amyl nitrite is a temporary intervention that is used in the prehospital settings, or if intravenous access is difficult, and until intravenous hydroxocobalamin or the sodium nitrite and sodium thiosulfate infusions can be administered.

Pregnancy Risk Factor C/ X

• Although no studies have been done, the manufacturer suggests that pregnant women avoid it as it can significantly lower your systemic blood pressure.
• Fetal hemoglobin can also be converted to methemoglobin.

Amyl Nitrite use during breastfeeding:

• You should be cautious while breastfeeding, as the excretion of this drug into breastmilk has not been determined.

Amyl Nitrite Dose in Renal Disease:

• No recommendations available

Amyl Nitrite Dose in Liver Disease:

• No recommendations available

Side Effects of Amyl Nitrite Frequency not defined.

• Cardiovascular:
  • Cerebral Ischemia
  • Facial Flushing
  • Hypotension
  • Orthostatic Hypotension
  • Shock
  • Syncope
  • Tachycardia
  • Vasodilatation
• Central Nervous System:
  • Dizziness
  • Headache
  • Increased Intracranial Pressure
  • Restlessness
• Dermatologic:
  • Dermatitis
  • Diaphoresis
  • Pallor
  • Skin Irritation
• Gastrointestinal:
  • Fecal Incontinence
  • Nausea
  • Vomiting
• Genitourinary:
  • Urinary Incontinence
• Hematologic & Oncologic:
  • Hemolytic Anemia
  • Methemoglobinemia
• Neuromuscular & Skeletal:
  • Weakness
• Ophthalmic:
  • Eye Irritation
  • Increased Intraocular Pressure

Contraindication to Amyl Nitrite Include:

• Glaucoma
• Recent head trauma or cerebral hemorhage.
• Pregnancy
• Concurrent carbon monoxide poisoning if used for cyanide poisoning.

Warnings and Precautions

• Hypotension
  • Hypotension can be caused by amyl nitrite, which can sometimes lead to serious complications. 
  • Before therapy can be initiated, the patient must be euvolemic.
  • Before using it, ensure that oxygenation and perfusion are adequate.
  • Patients with an undetermined diagnosis and patients with reduced cardiovascular reserve (like those who smoke, suffer from anemia, blood loss, or have cardiac disease) should be advised to avoid the drug.
  • These patients should be prescribed hydroxocobalamin.

• Methemoglobinemia:
  • This causes methemoglobin to form, which has a lower oxygen-carrying capability. Monitoring the patient is important to ensure adequate oxygenation.
  • Patients with an undetermined diagnosis, patients with anemia, bleeding disorders, or patients who have suffered from cardiac disease, such as smokers, heart attack victims, congenital methemoglobin deficiency, or patients with reduced cardiovascular reserve should be advised to avoid the drug. These patients should be given hydroxocobalamin.
  • Patients taking medications that cause methemoglobinemia such as nitroglycerin or phenazopyridine need to be warned.
• Aortic stenosis
  • Patients with aortic Stenosis should use it with caution due to the risk of impaired coronary perfusion that could lead to ischemia.
• Cardiovascular disease
  • It can cause hypotension, syncope and postural dizziness.
  • Patients with hypotension and patients with coronary artery disease are at particular risk.
• Increased intracranial pressure
  • Patients with recent head trauma or cerebral hemorhage should not use it.

Amyl nitrite: Drug Interaction

Note: Drug Interaction Categories:

• Risk Factor C: Monitor When Using Combination
• Risk Factor D: Consider Treatment Modification
• Risk Factor X: Avoid Concomitant Use

Monitoring Parameters:

• Blood pressure and heart rate during treatment
• Hemoglobin and Hematocrit
• Co-oximetry
• Serum lactate levels
• Arterial and venous partial pressure of oxygen gradient
• Serum methemoglobin and Oxyhemoglobin

How to administer Amyl Nitrite:

• Administer via nasal inhalation. Ask the patient to lie down.
• Crush the ampoule in a gauze piece and place it in front of the patient's mouth or endotracheal tube in intubated patients.
• Ask the patient to inhale it for 15 to 30 seconds.
• Repeat at one-minute interval until sodium nitrite can be administered. One ampoule lasts for about 3 minutes. 

Mechanism of action of Amyl Nitrite:

• It relaxes the blood vessels smooth muscle, lowers arterial blood pressure, reduces left-ventricular work and decreases myocardial oxygen intake.
• It promotes the formation-met hemoglobin, which competes for the cyanide-ions. Combining cyanide with met hemoglobin creates cyano-methemoglobin.
• This frees the cytochrome oxygenase and allows aerobic metabolism to continue.

It has been the beginning of action Within half an hour. The anti-anginal effects can last between 3 and 15 minutes. The effect lasts about 30 seconds when used to diagnose hypertrophic cardiomyopathy (pharmacologic stimulation of LVOT gradient).

It is easily available absorbed by inhalation through your respiratory tract.

Metabolized Inorganic nitrates are less potent and can be found in the liver.

Half-life elimination The time taken to prepare Amyl Nitride is less than an hour, while that for met hemoglobin takes one hour. 33% of the drug can be found in this form.

Excreted Via urine

Interantional Brands of Amyl Nitrite:

• Amyl Nitrite

Amyl Nitrite Brands in Pakistan:

No brands available in Pakistan.