Adequate completion of informed consent process with written documentation
Male and female patients, 18 - 70 years old, inclusive
Meets criteria for deployment related asthma or DRA (New onset of persistent respiratory symptoms of cough, dyspnea, wheezing and/or chest tightness during or after post-9/11/2001 military deployment to Southwest Asia, accompanied by a post-bronchodilator increase in FEV1 ≥ 12% and an increase in FEV1 ≥ 200 milliliters on pulmonary function testing and/or methacholine challenge showing airways hyperresponsiveness with a 20 percent drop in FEV1 (PC\[-20\] FEV1) ≤ 16 mg/mL. ) Historical results from previous studies or documented in clinical records within the last 24 months are acceptable alternatives
Able to perform reproducible spirometry according to ATS criteria
All racial/ethnic backgrounds may participate
Smoking tobacco history ≤15 pack years and no smoking in the last 3 months
Suboptimal asthma control at baseline (ACQ ≥ 0.5 or ACT\<19)
You may not be if
Respiratory tract infection within the 4 weeks prior to Visit 0
Pulmonary-related ER visit within the 4 weeks prior to Visit 0
Oral or systemic corticosteroid burst (for any indication) within the 4 weeks prior to Visit 0. One-time doses, such as intra-articular injections into a shoulder or knee joint, require a 2-week washout prior to Visit 0
Significant concomitant medical illness at the discretion of the PI, including (but not limited to) heart disease, cancer, uncontrolled diabetes, other chronic lung diseases
Chronic renal failure (creatinine \> 2.0) at Visit 0 (Associated with higher ADMA levels)
Positive urine (or serum) pregnancy test at Visit 0 or at any time during the study
Intolerance or allergy to L-arginine or L-citrulline
Concomitant use of PDE5 drugs or oral mononitrates
Unable or unlikely to complete study assessments in the opinion of the Investigator
Study intervention poses undue risk to patient in the opinion of the Investigator
