This is regarding my dad. He is 57 years old. Before 5 months back my dad is suffering from cough problem so we consult with local doctor and we have done the x ray and found that there is some water (Pleural Fluid) in right lung. So then we consult with chest and respiratory specialist doctor further we done the more test for this (Pleural Fluid) like AFB Culture, Cytology,and also we have done CT scan for chest and Sputum test all are regarding pulmonary tb. But all the report are showing normal. Also 15 days back we have done the bronchoscopy also for that one report came normal and we are now waiting for next report which will come after one month. This is case history Right now my dad taking the following medicine since last 4 months:- R-Cin 600 Rifampicin Capsules Ecox-800 Ethambutol Tablets Solonex Isoniazid Tablets 300 mg PYRIDOXINE HYDROCHLORIDE Tablets (VITAMIN B6) my question is how much time it require to cure this disease? Because my dad is still suffering from cough problem.