Acute Laryngitis: This is the most common cause of hoarseness, often resulting from a viral upper respiratory infection. It leads to inflammation of the larynx, affecting the vocal cords and causing hoarseness.

Vocal Cord Nodules or Polyps: These are growths on the vocal cords that can cause hoarseness due to overuse or misuse of the voice. They are common in singers, teachers, and others who use their voice extensively.
Gastroesophageal Reflux Disease (GERD): Stomach acid reflux can irritate the vocal cords, leading to hoarseness. This is more likely in individuals with a history of GERD symptoms.
Allergies: Postnasal drip from allergies can irritate the vocal cords, causing hoarseness.
Smoking: Smoking can cause chronic inflammation and irritation of the vocal cords, leading to hoarseness.

Laryngeal Cancer: Although less common, laryngeal cancer can present with hoarseness as an early symptom. It's crucial to investigate further, especially in smokers or those with a significant history of smoking.
Thyroid Disorders: Conditions like a thyroid nodule or goiter can compress the recurrent laryngeal nerve, leading to hoarseness.
Neurological Disorders: Such as Parkinson's disease, myasthenia gravis, or a stroke, which can affect the nerves controlling the vocal cords.

Relapsing Polychondritis: A rare autoimmune disorder that can cause inflammation of the larynx and trachea, leading to hoarseness.
Sarcoidosis: A condition that can cause granulomas in various parts of the body, including the larynx, leading to hoarseness.
Amyloidosis: A rare condition where abnormal proteins (amyloid) accumulate in various organs, including the larynx, potentially causing hoarseness.
Foreign Body: In rare cases, especially in children, a foreign body in the larynx or trachea can cause hoarseness.