Pulmozine was a drug used to treat oxygen deprivation and stimulate breathing.
In 2372, The Doctor gave 40 milligrams of pulmozine to one of Seska's aides, Teirna, after he was brought aboard the USS Voyager. (VOY: "Basics, Part I")
In 2373, The Doctor used pulmozine to stimulate breathing in Lieutenant B'Elanna Torres after she was injured during an attack on the Nasari. (VOY: "Favorite Son")