AMYL NITRITE (am'il)
Amyl Nitrite Classifications: nitrate vasodilator; antidote; Therapeutic: antidote; nitrate vasodilator Prototype: Nitroglycerin Pregnancy Category: X
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Availability
0.3 mL ampules
Action
Short-acting vasodilator and smooth muscle relaxant. It is converted to nitric oxide, which causes the vasodilation. Action
in treatment of cyanide poisoning is based on ability of amyl nitrite to convert hemoglobin to methemoglobin, which forms
a nontoxic complex with cyanide ion.
Therapeutic Effect
Effective for immediate treatment of cyanide poisoning.
Uses
As an adjunct antidote in the immediate treatment of cyanide poisoning. (Because of adverse effects, unpleasant odor, and
expense, infrequently used to treat angina pectoris.)
Unlabeled Uses
Change intensity of heart murmurs.
Contraindications
Hypersensitivity to nitrites or nitrates; severe anemia; uncontrolled hyperthyroidism; acute alcoholism; pregnancy (category
X).
Cautious Use
Elderly; recent increase in intracranial pressure; cerebral hemorrhage, head trauma; hypotension; glaucoma; recent MI; lactation,
children.
Route & Dosage
Acute Angina Adult: Inhalation 0.180.3 mL prn
Cyanide Poisoning Adult/Child: Inhalation 0.3 mL perle crushed every minute and inhaled for 1530 s until sodium nitrite infusion is ready
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Administration
Inhalation
- Crush ampule between fingers to prepare (amyl nitrite is available in 0.18 mL and 0.3 mL perles, which are thin, friable
glass ampules enveloped with woven fabric cover).
- Instruct patient to sit a while immediately after drug is administered.
- Note: Amyl nitrite is volatile and highly flammable; when mixed with air or oxygen, it forms a mixture that can explode if ignited.
- Store at 8°15° C (46°59° F), unless otherwise directed. Protect from light.
Adverse Effects (≥1%)
Body as a Whole: Transient flushing, weakness.
CV: Orthostatic hypotension, palpitation,
cardiovascular collapse, tachycardia.
GI: Nausea, vomiting.
Hematologic: Methemoglobinemia (large doses). CNS: Headache, dizziness, syncope.
Respiratory: Respiratory depression.
Pharmacokinetics
Absorption: Rapidly from mucous membranes.
Onset: 1030 s.
Duration: 35 min.
Nursing Implications
Assessment & Drug Effects
- Monitor for S&S of syncope, due to a sudden drop in systolic BP, which sometimes follows drug inhalation, particularly in
older adults.
- Monitor vital signs until stable. Rapid pulse, which usually lasts for a brief period, is an expected response to the fall
in BP produced by the drug.
- Chart length of time required for pain to subside after administration of drug.
- Note: Tolerance may develop with repeated use over prolonged periods.
Patient & Family Education
- Note: Drug has a strongly fruity odor.
- Go to the emergency room immediately or consult physician if no relief from angina is experienced after 3 doses 5 min apart.