Pleurisy Root as Mahuang ??

I was browsing in William Cook's The Physio-Medical Dispensatory, where I came upon his account of Pleurisy Root (asclepias tuberosa). Allow me to share a few passages: "The root of this plant is probably one of the most reliable and serviceable relaxing diaphoretics in the whole Materia Medica. ... Its principle action is upon the sweat glands ... The chief employment of this agent is in febrile and inflammatory affections, where the perspiration needs to be decidedly promoted ... It secures a slow, steady, and free perspiration, and the same time suitably diminishing excessive heat on the surface; which action renders it highly serviceable in [various fevers] and other forms of fever with hot skin and a rigid pulse ... Most commonly it is combined with some diffusive and more prompt stimulant, especially about one-fourth its own weight of ginger [and, I would add, guizhi]."

This seems to set us up perfectly to use Pleurisy Root in a Mahuang Tang type formula. But does it open the Lungs, for use in a Ma Xing Shi Gan Tang type formula? Ellingwood & Lloyd (1915), list Pleurisy Root in their chapter on "Agents Acting Upon the Respiratory Tract." They say: "It is of special service in the treatment of affections involving the serous membranes, as pleuritis, peritonitis, etc. ... It is beneficial in acute pleuritis specifically, also in bronchitis, pneumonitis, and peritonitis. It has distinct expectorant properties. In tight and painful coughs with difficult respiration, especially where there is a general suppression of secretion, with dry skin and mucous membranes, and in soreness of the chest from coughing, it is a most excellent remedy." That seems to line up pretty well, but I cannot tell whether it is working on the lungs through the same mechanism as Ma Huang. I have not yet seen wheezing mentioned specifically although "difficult respiration" comes pretty close. I'm not sure that I would rely on it in a case of whooping cough.

In terms of flavor, Holmes calls Pleurisy root bitter and pungent, which is how Bensky lists Mahuang. Holmes considers Pleurisy Root to be a cold herb, however, Matthew Wood (1997) notes that Pleurisy Root is called for in patients who are worse in the cold and damp.