Inclusion Criteria:

1. Adult between the ages of 18 and 60.
2. patient who has cough symptom caused by following diaseses: Chronic Bronchitis, Asthma, Bronchiectasis, Gastroesophargeal Reflux Disease, Postnasal drip syndrom caused by rhinitis, sinusitis, rhinopharyngitis, rhinolayngitis.
3. Patient requiring internal treatment due to cough symptom, who has coughing more than 3 weeks.
4. Patinet who decided to participate in theis clinical trial at his(her) own will and agreed in written letter of consent.
5. Patient who is trustworthy, ready for cooperation and observing the restrictions during the trial period.

Exclusion Criteria:

1. Patient who is accompanied by the seriously abnormal symptom in respiratory system, such as Acute infectious Pulmonary Disease, Tuberculosis.
2. Patient who has clinical history of sensitivity to Xanthine drug.
3. Patient who pas Peptic Ulcer (Except Cicatrix)
4. Patient whose liver or kidney function is seriously abnormal: Including the cases of sGOT, sGPT, bilirubin and blood creatinine value exveeding twice of their upper normal limit.
5. Patient whose heart function is abnormal: including the case of showing abnormal EKG test value that is clinically significant.
6. Patient who has experinece to have participated in other clinical trial whithin two months before starting the trial.
7. Pregnant woman, latating woman.