Hello,
There are many conditions which can cause difficulty in speaking at higher pitches. Voice misuse and overuse are common causes. Acute
laryngitis caused by allergies, viral infection, chronic laryngitis and laryngoesophageal reflux all can cause hoarseness and voice difficulties. Rare but serious causes producing these symptoms are vocal cord paralysis and vocal cord tumours.Please see your Otolaryngologist (Ear, Nose, and Throat doctor) for an evaluation.