Follicular pharyngitis can be secondary to acute pharyngitis, chronic inflammation of the tonsils, upper and lower respiratory tract infections, etc. It can also be caused by damage to the mucous membrane of the pharynx through inhalation of dust, harmful gases, consumption of spicy and irritating foods, etc. It can also be secondary to some systemic diseases (e.g. anaemia, indigestion, cardiovascular disease, endocrine disorders and immune deficiency).