The purpose of this clinical trial is to evaluate the acute bronchitis symptom relief effect of Bronpass tab. compared to Erdos capsule, and compare and evaluate the safety.

The purpose of this clinical trial is to evaluate the following in patients with acute bronchitis at the 7th day of administration of the investigational drug.

primary purpose: Prove the non-inferiority of the acute bronchitis symptom relief effect of Bronpass tab. compared to Erdos capsule, and compare and evaluate the safety.

secondary purpose: Compare and evaluate the effect of improving clinical symptoms, including sputum symptoms, of Bronpass tab. compared to Erdos capsule.

Inclusion Criteria:

1. Adult aged 19 to 80 at the time of screening
2. Patients with an acute bronchitis severity score (BSS) of 5 or higher at the time of screening and the first day of administration of the investigational drug
3. Patients with symptoms of acute bronchitis within 48 hours from the time of screening
4. Patients who voluntarily gave written consent to participate in this clinical trial

Exclusion Criteria:

1. Patients with a known hypersensitivity reaction to the components of this investigational product
2. Patients with respiratory and systemic infections requiring systemic antibiotic treatment
3. Patients with clotting disorders or bleeding tendencies
4. Patients with peptic ulcer at the time of screening
5. Severe lung diseases that may affect the efficacy evaluation of this clinical trial at the discretion of the investigator
6. For screening test results, creatinine clearance < 25 mL/min or AST, ALT more than 3 times the upper limit of normal
7. A person who have administered systemic corticosteroids or immunosuppressants within 4 weeks of the first administration of the investigational drug
8. A person who have administered antiviral drugs, systemic/inhaled glucocorticosteroids within 48 hours of the first administration of investigational drugs
9. A person who have administered mucolytics, sputum discharge agents, antitussives, herbal medicines with antitussive/ expectorant effects, and antihistamines within 48 hours of the first administration of investigational drugs
10. A person who need or plan to take contraindicated drugs or therapies during this clinical trial period
11. Patient with liver cirrhosis or cystathionine synthetase deficiency
12. Patient who have clinically significant diseases and disorders in the cardiovascular system, endocrine system, and central nervous system at the time of screening, or who have a history of malignant tumors or mental disorders (eg. depression) (However, participation is possible if there is no recurrence for more than 5 years after surgery at the time of screening)
13. A person with a history of alcoholism or drug abuse
14. Heavy smokers (more than 15 cigarettes per day) within 4 weeks from the time of screening
15. Pregnant or lactating
16. Among female subjects of childbearing potential, women who do not intend to use appropriate contraceptive methods or plan to become pregnant during this clinical trial
17. A person who administered other investigational drugs within 4 weeks from the time of screening
18. A person who are not suitable for participation in this clinical trial under the judgment of the investigator