The classification of antiarrhythmic drugs.

The Vaughan Williams system of classification of antiarrhythmic drugs provides valuable information concerning their electrophysiologic effects and mechanism of action. Despite its limitations in predicting the clinical effectiveness for treatment of specific arrhythmias, this classification is helpful in allowing many correlations between different drugs and their expected actions and adverse effects.

Nuclear medicine evaluation of motion sickness and medications on gastric emptying time.

Diminished gastric motility and lack of bowel sounds have been observed in astronauts aboard the Space Shuttle (4). In this study subjects were given scopolamine 0.6 mg with d-amphetamine 5 mg with and without neostigmine 15 mg.

Mechanisms of antimotion sickness drugs.

Unlabelled: Eight subjects, male and female, were rotated using the step method to progressively increase the speed of rotation (+2 rpm) after every 40 head movements to a maximum of 35 rpm. The end-point for motion sickness was the Graybiel Malaise III total of symptoms short of frank nausea. The drug treatments were placebo, scopolamine 0.

Study of dose-dependence and urinary folate excretion produced by ethanol in humans and rats.

Acute ethanol ingestion by human alcoholic subjects produces a marked decrease in serum folate levels within 16 hr. A similar decrease occurs in rats and can be explained by a marked increase in urinary folate excretion following ethanol treatment. To assess the effects of acute ethanol ingestion on urinary folate excretion in healthy human volunteers, two studies were carried out at initial ethanol dose levels of 0.

Acute ethanol ingestion by humans and subacute treatment of rats increase urinary folate excretion.

Previous studies with rats showed that acute treatment with ethanol (4 g/kg) produce a marked increase in urinary folate levels, followed by a decrease in plasma folate levels. Analogous studies with human volunteer subjects using a lower dose of ethanol showed that there were small, but statistically significant increases in urinary folate levels after four hours. The initial ethanol dose was 1.