Yanlishuang Buccal Dropping Pills for Acute Pharyngitis

Acute pharyngitis commonly causes sore throat and pain on swallowing. This multicenter trial will compare Yanlishuang Buccal Dropping Pills with a matching placebo in 400 adults aged 18 to 65 years whose acute pharyngitis began within 48 hours and whose baseline throat-pain visual analog scale score is at least 4. Participants will be randomized 1:1 and treated under double-blind conditions. Each group will use four buccal dropping pills 4 to 6 times daily at intervals of at least 2 hours for up to 5 days. Participants whose sore throat resolves after at least 72 hours and remains absent for at least 24 hours may stop treatment early. The primary outcome is time to complete sore throat resolution. Secondary outcomes assess immediate pain relief, onset and resolution of pain, symptom and physical-sign response, complications, and work absence. Safety will be assessed using physical examinations, vital signs, laboratory tests, electrocardiograms, and adverse events.

Inclusion Criteria: * Age 18 to 65 years, inclusive, of any sex. * Baseline throat-pain visual analog scale score of at least 4. * Meets the protocol-defined Western medicine diagnostic criteria for acute pharyngitis. * Acute onset with disease duration of 48 hours or less. * Provides written informed consent and is able to follow the study protocol. Exclusion Criteria: * Prior use of Yanlishuang Buccal Dropping Pills before enrollment, or use before enrollment of any other Chinese or Western medicine for the target disease that, in the investigator's judgment, may affect efficacy evaluation. * Prodromal or accompanying throat symptoms of an acute infectious disease, such as measles, scarlet fever, or infectious mononucleosis; suppurative tonsillitis; peritonsillar abscess; retropharyngeal abscess; acute epiglottitis; or throat symptoms caused by another disease. * Modified Centor score of at least 2, with white blood cell count, absolute neutrophil count, and C-reactive protein all above the upper limit of normal, when the investigator considers bacterial infection or antibiotic treatment necessary. * Concurrent bacterial otitis media, sinusitis, laryngitis, bronchitis, pneumonia, acute nephritis, rheumatic fever, sepsis, or a similar complication. * Severe primary disease of the central nervous, hematopoietic, endocrine, cardiovascular/cerebrovascular, digestive, or other system, or a psychiatric disorder, that the investigator considers may affect participant safety or materially affect clinical evaluation. * Abnormal hepatic or renal function: alanine aminotransferase or aspartate aminotransferase greater than 1.5 times the upper limit of normal and/or serum creatinine above the upper limit of normal. * Suspected or confirmed history of alcohol or drug abuse. * Pregnancy, breastfeeding, preparation for pregnancy, or a recent childbearing plan. * Known allergy to any component of the study medication. * Participation in another clinical trial and use of an investigational product within the previous 1 month. * Constitutional spleen-stomach deficiency-cold or a condition considered unsuitable for study medication, including but not limited to acute or chronic gastritis, erosive gastritis, or gastroesophageal reflux disease. * Any other condition that the investigator considers makes the individual unsuitable for participation.