This is a prospective, single-arm, open-label, pilot clinical study to evaluate the efficacy and safety of nasopharyngeal administration of 13.6% high-concentration 35 kDa hyaluronan (HA35) care gel in subjects with chronic rhinitis and chronic pharyngitis. Eligible participants will receive the study gel twice daily for 10 consecutive days. The primary objectives are to assess rapid changes in nasopharyngeal discomfort, posterior pharyngeal discomfort, and nasal obstruction within 30 minutes after the first administration. Secondary objectives include evaluation of overall symptom improvement at day 10, changes in subjective mental clarity, and safety and tolerability throughout the treatment period. This is a minimal-risk, non-pharmacological supportive care intervention.

This prospective, single-center, single-arm, open-label pilot clinical study is designed to investigate the efficacy and safety of a 13.6% high-concentration 35 kDa hyaluronan (HA35) nasopharyngeal care gel for the management of chronic rhinitis and chronic pharyngitis.

Participants meeting all eligibility criteria will receive the HA35 gel via nasopharyngeal administration, one unit per nostril, twice daily (morning and evening) for 10 consecutive days.

Symptom assessments will be performed at baseline, 30 minutes after the first administration, 1, 2, and 3 hours after the first morning dose, and on day 10. Assessments include numeric rating scales (NRS) for nasopharyngeal discomfort, posterior pharyngeal discomfort and cough, nasal airflow obstruction, overall rhinitis and pharyngitis symptom severity, and subjective mental clarity.

Safety evaluations will monitor all adverse events, local tolerability, and any unexpected reactions throughout the study period.

This study involves a non-invasive, non-pharmacological non-drug intervention with minimal risk to participants. All procedures will be conducted in accordance with the Declaration of Helsinki, and written informed consent will be obtained from all subjects prior to enrollment.

Inclusion Criteria:

• Age 18-80 years, male or female
• Clinically diagnosed with chronic rhinitis and chronic pharyngitis for ≥3 months
• Baseline nasopharyngeal discomfort NRS score ≥4 points
• Baseline posterior pharyngeal discomfort NRS score ≥4 points
• Voluntary participation and signed written informed consent
• Ability to complete symptom assessment independently

Exclusion Criteria:

• Acute upper respiratory tract infection within 2 weeks
• Use of antihistamines, intranasal corticosteroids, decongestants, or other nasal medications within 2 weeks prior to screening
• History of nasal/sinus surgery within 6 months
• Known hypersensitivity to hyaluronan or any gel ingredients
• Pregnant or lactating women
• Severe systemic diseases or malignant tumors