Before Ibuprofen can relieve your headache, it has to dissolve in your bloodstream. The problem is Ibuprofen, in its native form, isn't particularly soluble. Its rigid, crystalline structures -- the molecules are lined up like soldiers at roll call -- make it hard to dissolve in the bloodstream. To overcome this, manufacturers use chemical additives to increase the solubility of Ibuprofen and many other drugs, but those additives also increase cost and complexity.
from Geochemistry News -- ScienceDaily http://ift.tt/1MRTHap