Laryngitis is an inflammation of the mucous membranes of the larynx. Signs of laryngitis include hoarseness and loss of voice. The most common causes are excessive meowing and a chronic cough. Both cause vocal cord strain.
Laryngitis can be associated with tonsillitis, throat infections, tracheobronchitis, pneumonia, inhalant allergies, and (rarely) tumors in the throat. The lining of the larynx is not coated with cilia. Therefore, mucus frequently accumulates in the larynx. Exaggerated throat clearing is needed to dislodge it. This further irritates the larynx and lowers resistance to infection.
Brushing your cat not only removes dirt, grease and dead hair from her coat, but it helps to remove skin flakes and stimulates blood circulation, improving the overall condition of her skin. One or two brushings per week will help kitty to keep her healthy glow and allow her to bask in yummy together time-and you’ll find that regular sessions are especially beneficial when your cat ages and is no longer able to groom so meticulously on her own.
Treatment: Laryngitis due to excessive meowing usually responds to removing the cause of the cat’s anxiety or distress. If the problem is due to prolonged coughing, seek veterinary attention to investigate and eliminate the cause of the chronic cough.
WebMD Veterinary Reference from "Cat Owner's Home Veterinary Handbook"