An extract of an herb that is made according to official (and unofficial) pharmaceutical practice, with a strength of 1:1. That means each ounce of the fluidextract has the solutes found in an ounce of the dried herb. Advantageous for some herbs (such as Arctium or Taraxacum), where the active constituents retain the same proportions as in the plant, even though reduced to a very small volume of menstruum, it is deadly for others (such as Hydrastis or Lobelia), whose constituents may have wildly varying solubility, and whose fluidextract will contain only the most soluble constituents and lack others completely. The gradual disappearance of herbal preparations in Standard Medicine in the 1930s can partly be attributed to the almost complete reliance on fluidextracts. Some manufacturers (notably Lilly and SK&F) sold Tinctures (1:5 strength and meant to, at the least, contain EVERYTHING in the plant) that were made from diluted fluidextracts. Some fluidextracts were even made from dilutions of what were termed Solid Extracts....heat-evaporated tars, easy to store, easy to make in huge labor-minimal batches, where 100 pounds of Blue Cohosh could be reduced to 25 pounds of solid extract. This convenience pitch, with many constituents oxidized by heat, others never even extracted, could be diluted four times to sell as a fluidextract, TWENTY time to market as a tincture. These practices by American pharmaceutical manufacturers, with eyes perhaps on the larger drug trade (the use of crude drugs being a diminished part of their commerce, yet needing MANY different preparations...and being labor-intensive and profit-minimal...and sort of old-fashioned) ended up supplying terminally impaired products. Their value being reduced, physicians relied more and more on mainstream pharmaceuticals...and the medical use of whole plant preparations died.
Health Encyclopedia