Laburnum Poisoning and Cytisine.

Abstract

THE common laburnum tree, Cytisus laburnuont, was shown by Gray, in 1862 [1], to contain an alkaloid which he named "cytisine." This alkaloid has been found in a number of other plants, and has since been investigated from a chemical point of view by Husemiiann and Marme [2], Partheil [3], and others. Its physiological action has been examined and described by Gray, Husemann and Marme, Cornevin [4], Prevost and Binet [5], and Radziwillowicz [6]. The poisonous effects of laburnum are usually attributed to the presence of cytisine in the plant. As' Dr. Dale and I have recently been engaged in re-investigating the action of cytisine, and have been able to determine its pharmacological effects with greater accuracy and fuller detail than previous workers, I thought it might be interesting to analyse a number of poisoning cases in man, and show that such new facts as we have discovered confirm the view that the alkaloid is responsible for the poisonous properties of the plant. A large number of cases of accidental poisoning are recorded. Radziwillowicz collected 181 cases in 1888, and since that date additional cases have been described. The great majority of these occur in children, and are for the most part miild; fatal cases are rare. Three are described in the British Medical Journal [7 and 8] and one in the Lancet [9]; Radziwillowicz records others. The milder cases [10] run a course somewhat as follows: A child swallows a few laburnum seeds under the impression that they are peas; or he eats the flowers, pods, or leaves, possibly in search for a new sensation in flavours. About an hour afterwards the child feels unwell, complains of being unable to walk, or seems weak and helpless. Some complain of headache, giddiness , and stomach-ache. Shortly after the onset of these symptoms he vomits and appears to be very ill. The skin of the face in particular is pale, cold, and moist, the pulse rapid and thin. The pupils may be contracted at first, but dilate in the later stages; they react to light in mild cases. Sickness continues, and purgation may occur. The recorded cases among adults are not severe, and usually have their origin in the mistaken use of laburnum flowers to flavour dishes.