The _Lathyrus_ is a vetch, and a member of the leguminosae family growing
in India.
This remedy, which produces a perfect picture of certain spinal
affections, has been known for over a century. In _Christison's
Toxicology_ it is stated that it causes paraplegia, dragging gait,
turning-in of the toes, stiffness and semi-flexion of the knee-joints.
The attention of the homoeopathic profession was directed to the drug
as a possible remedy in paraplegia, in the _British Journal of
Homoeopathy_, Vol. III. Here is found an account of a wheat famine in
India, where the peas of the plant were substituted for wheat and used
as a food. Those who subsisted on it were taken, even during sleep,
with sudden paralysis of the lower limbs; this occurred without
warning, in young men more than in young women, and was never recovered
from. Another observer records fifty cases who had eaten the _Lathyrus_
bread and all stated that they became paralytic during the wet season of
the country, that they went to bed quite well and awoke with stiff legs,
unsteady gait, and aching, but no severe pain. The upper extremities
were free.
Another who saw the disease in Algeria and described the symptoms found
in ten cases observed that they came on suddenly, in damp weather, with
some pains in the loins, trembling, motor paralysis and exaggerated
reflexes. He attributed these phenomena to an acute transverse myelitis
with degenerative changes in the cord.
A German writer states that the drug produces disturbances of nutrition
of the muscles of the lower extremities, paresis, and that the muscles
of the trunk and neck and face remain unaffected. Sensation remains
normal. It seems to produce a sclerosis of the pyramidal tracts of the
cord.
In animals the same condition is found; namely, paralysis of the hind
legs. Pigs drag their hind legs and horses give out.