Lower airway inflammation and mucus hypersecretion are hallmark symptoms of acute bronchitis. Bronchipret ® TP (BRO), a fixed combination of thyme and primula dry extracts, previously demonstrated anti-inflammatory activity in the respiratory tract. Here, we report on its capability to normalize goblet cell hyperplasia and MUC5AC production in both an in vivo animal model and air-liquid interface (ALI) cell culture. In rats, bronchoalveolitis was induced by intratracheal LPS instillation. BRO was given daily at 68-680 mg/kg for up to 3 days. At 24h intervals up to 72h post LPS challenge epithelial goblet cell numbers as well as bronchial MUC5AC protein expression were analyzed. In vitro , human airway epithelial ALI cultures were stimulated for 14 days with IL-13 to induce goblet cell hyperplasia and MUC5AC production. Cells were cotreated basolaterally with BRO. Quantitative microscopical analyses were performed in ALI cross sections after Alcian blue staining for goblet cell detection or immunohistochemical MUC5AC staining. LPS increased both bronchial goblet cell density as well as MUC5AC levels. Treatment with BRO significantly reduced MUC5AC as well as goblet cell numbers. The magnitude of these effects was comparable to that of dexamethasone. These findings were supported in vitro : IL-13 stimulation led to goblet cell hyperplasia and increased MUC5AC production. Co-treatment with BRO normalized these effects. In conclusion, Bronchipret ® TP film-coated tablets normalizes pathologically altered determinants of viscous mucus secretion in vivo and in vitro . These effects most likely contribute to the clinical efficacy of Bronchipret ® in acute bronchitis.