Regional cerebral blood flow changes associated with amyl nitrite inhalation.

Regional cerebral blood flow (CBF), mood states and somatic symptoms were measured before and after inhalation of amyl nitrite in 10 physically healthy volunteers with a prior history of using volatile nitrites for recreational purposes. CBF was measured with the same technique, under identical laboratory conditions, in an equal number of normal volunteers. During CBF measurements, blood pressure, pulse rate, respiratory rate and end-tidal levels of carbon dioxide were monitored. The amyl nitrite group and the control group were compared on CBF, rating scale scores and physiological indices via analysis of variance. Amyl nitrite inhalation was associated with significant global increases in CBF, while the control group did not show any change. Pulse rate increase was the only physiological change associated with administration of the drug. Subjects who received the drug reported significant decrease in anger, fatigue and depression and increased palpitation, breathing difficulty, dizziness and headache. Changes in the rating scale scores, physiological indices, and somatic symptoms after amyl nitrite did not correlate with regional CBF change.