Available in tablets of 200mg, prescription drug generic Pirfenidone is suggested for Idiopathic Pulmonary Fibrosis (IPF) cases, which are not very severe. It is a rare disease, which causes the lungs to have scars or become thick. The changes caused to the lungs by this condition make it very difficult for the patient to respire properly. Usually it affects individuals between the age group of 50 and 70 years.