The narcotic effect begins to manifest itself about a half hour after eating, in a pulling and jerking of the muscles or a so-called tendon jump, though sometimes these effects appear only after an hour or two. The narcotic substance contained in fly-agarics retains its effectiveness permanently and can be transmitted to other persons by drinking the ingester's urine. This has long been a practice in Siberia. The smaller mushrooms, which are bright red and covered with many white warty spots, are said to be far stronger in narcotic power than the larger ones, which are pale red and have few white spots.
Effects vary with individuals, source of mushroom, and dose.
The usual pattern is dizziness, twitching and some nausea after 30 minutes, followed by numbness of feet and twilight sleep for 2 hours, with colorful visions and intensified awareness of sounds. After this, one may feel buoyant with great energy and strength. Hallucinations and distortion of size are common. The entire experience lasts about 5-6 hours. Side effects include flushing of the skin and lethargy.