Experimented using WD-40 (aerosol lubricant) to nuke drywood termites, and seemed to work. First squirted in their holes where they were ejecting granules. A lot of fluid missed going into the hole, so on the single ejection hole that formed somewhat later, a soft piece of cardboard was cupped to direct all fluid inside. Boy, did that hole suck in petro-cocktail, by capillary action or whatever.
Well, no guarantees, but their long period of activity seems to have come to a halt. Only dared tried it because that furniture was the only worthwhile stick of wood in a concrete structure. And official drywood termite treatment is expensive and inconvenient (remember drywood termites are TOTALLY different than the more typical kind of termite which require moisture, mudtubes etc).