"Drink plenty of fluids": a systematic review of evidence for this recommendation in acute respiratory infections

Abstract

Doctors often recommend drinking extra fluids to patients with respiratory infections. Theoretical benefits for this advice are replacing insensible fluid losses from fever and respiratory tract evaporation, correcting dehydration from reduced intake, and reducing the viscosity of mucus. To many this advice is self evident and justified on the basis that even if the benefit is uncertain, or at best small, at least it is harmless.