years ago, when i first came to curezone for sinus issues (since resolved), pine bark extract was one of the best remedies i had to get me through the day. It had almost immediate effect of making me feel better, and opening up the sinuses. I think it was the potent anti-oxident effect, but i could be wrong.
"PCOs or OPCs were discovered in 1947 by Prof. Jacques Masquelier, who developed and patented techniques for the extraction of oligomeric proanthocyanidins from pine bark and grape seeds.[1]"