IRCT201506181165N5 IRCT 2015-07-13 Research deputy of Baqiyatallah University of Medical Sciences Examining the effect of NAC tablet on improving lung problems caused by mustard gas in chemically-wounded patients and veterans Assessment of efficacy and safety of Iranian version of NAC and comparing it with foreign sample of NAC in controlling pulmonary symptoms caused by sulfur mustard in chemically-wounded patients and veterans 2015-07-06 anticipated 84 Complete https://irct.ir/trial/307 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Not used, Assignment: Parallel, Purpose: Treatment, Other design features: We used the block randomization technique as the randomization procedure in our trial; if Oslyt group is shown by the letter A and Fluimucil group by B, randomization blocks are quaternary, i.e., AABB, BBAA, BABA, ABBA, ABAB and BAAB. In total, 21 blocks are established and patients are allocated to Oslyt or Fluimucil by these blocks and therefore, randomized. N/A Chronic respiratory disorders caused by chemical weapons (sulfur mustard; mustard gas). Intervention 1: In the control group, patients consume the standard treatment of Foreign NAC (Fluimucil) with a total daily dosage of 1800 mg (three times a day and each time a 600 mg effervescent oral tablet) for four months. Intervention 2: In the intervention group, patients consume the Iranian NAC (Oslyt) with a total daily dosage of 1800 mg (three times a day and each time a 600 mg effervescent oral tablet) for four months.