Opoponaco is a gomoresin that is obtained by drying the sap that flows from the incisions made in the root collar of the chironium opoponax, umbelifera that grows on the slopes of El Piul de Rivas, Sierra Morena and other parts from Spain and in the East.
It appears in irregular pieces, rarely in tears, a reddish yellow on the outside and a dirty white veined red and yellow on the inside; It is opaque, dry and friable. It has a rather strong aromatic smell, but unpleasant and a bitter and pungent taste. It contains resin, gum and a little starch. It is assured that the European plant does not give the opoponaco but it is very likely that if the same operation were done with it as with the Syrian one, it would do so in a lesser amount.
It is exciting, it is administered in lamparonic infarcts and as a beaker in catarrhal affections. Enter the composition of many plasters, ointments and liniments.
Veterinary Dictionary, Carlos Risueño, 1833
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