Pharyngeal follicular hyperplasia is a sign, not a disease, and coughing up sputum has nothing to do with pharyngeal follicular hyperplasia. Sputum is a little more viscous than saliva and may originate from nasal and sinus secretions in the upper respiratory tract or from the lower respiratory tract, suggesting the presence of inflammation associated with the upper or lower airways. As the secretions from the respiratory tract are transported backwards through the mucosal ciliary mucus system and concentrated in the oropharynx, this may cause the sputum to be coughed up to be more viscous.