MARACAIBO, Venezuela—Desperate and cashless Venezuelans, angry that the government hasn’t exchanged their voided bank notes as officials had pledged, on Friday rose up in protest with some scattered looting of stores.

National Guard troops were deployed to put down the unrest that broke out as far west as this large city near the Colombian border and in smaller towns in the east. With only nine days to go before Christmas, Venezuelans grappling with a collapsing economy and soaring inflation are left without money after President...