Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
tussiens, entis, m., one who has a cough: nuces tussientibus inimicae, Plin. 23, 8, 77, § 147; 21, 20, 83, § 140; 29, 3, 11, § 42.
tussĭo, īre, v. n. [tussis], to cough, to have a cough: forte si tussire occoeperit, ne sic tussiat, Ut cuiquam linguam in tussiendo proferat, Plaut. As. 4, 1, 49 sq.: male, Hor. S. 2, 5, 107: crebro, Quint. 11, 5, 56: plurimum, Petr. 117: acerbum, Mart. 2, 26, 1.