Concern was first raised in southwestern France. People who have been poisoned have all had three or more meals containing "T. equestre" within the last two weeks prior to treatment. One to four days after their last meal containing the fungus, the patients reported weakness of the muscles, sometimes accompanied by pain. This weakness progressed for another three to four days accompanied by a feeling of stiffness and darkening of the urine. Periods of nausea, sweating, reddening of the face were also registered, but there were no fevers.