To evaluate the analgesic effect of benzydamine hydrochloride dripping on the endotracheal tube cuff for postoperative sore throat.

The investigators will assign patients into either the benzydamine hydrochloride or the control group. The whole ETT cuff will be either dripped with 3 ml (4.5 mg) of benzydamine hydrochloride or nothing 5 minutes prior to anesthesia induction. The incidence and severity of POST at 0, 2, 4, 6, 12 and 24 hours postoperatively will be assessed. The potential adverse effects of benzydamine hydrochloride (throat numbness, throat burning sensation, dry mouth and thirst) will also be evaluated.

Inclusion Criteria:

• Patients aged 18-65 years
• ASA status I-II
• Mallampati grade I-II
• Duration of surgery less than 4 hours
• Patients placed in the supine position

Exclusion Criteria:

• Undergoing oral, cervical spine or thyroid surgery
• More than one attempt of ETT intubation or intubated with a technique of rapid sequence induction with cricoid pressure
• Insertion of nasogastric/orogastric tube or esophageal stethoscope
• Complaint of sore throat or hoarseness
• Presence of upper respiratory tract infection within 7 days prior to the operation
• Gastroesophageal reflux
• Known allergy to benzydamine hydrochloride or other nonsteroidal anti-inflammatory drugs (NSAIDs)