Properties : A liquid containing about 80 per cent, of amyl (chiefly isoamyl) nitrite. It should be kept in hermetically sealed glass bulbs or in dark, amber-colored, glass-stoppered vials. in a cool, dark place. Amyl nitrite is a clear, yellowish liquid of a peculiar, ethereal, fruity odor and a pungent, aromatic taste. It is very volatile even at low temperatures, and is inflammable. It is practically insoluble in water, but miscible in all proportions with alcohol or ether.

Action and Uses: When given by inhalation, amyl nitrite produces an almost instantaneous dilatation of the peripheral blood-vessels, shown by redness of the skin beginning in the head and neck, rapidly spreading over the body and sometimes extending to the lower extremities. This is promptly followed by a dilatation of the splanchnic and other vessels so that the blood-pressure soon falls. The lowered pressure increases the heart-rate. There is a feeling of fulness in the head, often accompanied by headache. The breathing is rapid. With excessive doses unconsciousness may supervene, and convulsions may occasionally occur after toxic doses. Large doses kill by respiratory paralysis. It may produce methemoglobin in the blood and cause the excretion of sugar in the urine. As much as 0.6 c.c. may be inhaled without dangerous results.

The effects of the medicinal administration of amyl nitrite are very transient. It is employed to relieve spasm in epilepsy, sometimes averting an expected paroxysm. It is also used to relax the spasm of the blood-vessels in angina pectoris and in other painful affections in which there is reason to believe that the pain depends on arterial spasm.

Amyl nitrite is given to reduce the blood-pressure in cases in which hemorrhage is due to the rupture of a blood-vessel in the lungs, brain or other organ in consequence of elevated blood pressure, but in hemorrhage with normal blood-pressure it may do harm. It has been used with favorable results in bronchial asthma.

Dosage: 0.2 c.c. or 3 minims, by inhalation.    It is conveniently carried in the form of glass pearls,   each pearl containing a dose. When required the pearl is  crushed in the handkerchief and the contents inhaled.