LSD: autoradiographic study on the placental transfer and tissue distribution in mice.

(14)C-lysergic acid diethylamide administered intravenously passed in a few minutes from the blood into the tissues. In addition to the brain, the adrenals, hypophysis, kidneys, liver, and lungs showed the highest uptake, much higher than the blood concentration. Excretion into the bile started immediately; this was the most inmportant elimination route. In the early stage of pregnancy, 2.5 percent (and in the late stage, 0.5 percent) of the radioactive dose passed the placental barrier into the fetus in 5 minutes. Over 70 percent of this fetal radioactivity was unchanged (15)C-lysergic acid diethylamide.