Growth Hormone Replacement in Veterans With GWI and AGHD (GWIT)

Inclusion Criteria: 1. veteran of the Gulf War conflict with a history of deployment to Operation Desert Storm or Desert Shield between 1990-91 2. age less than or equal to 64 years old 3. have a diagnosis of Gulf War Illness assessed by study investigators 4. have adult growth hormone deficiency diagnosed by glucagon stimulation test (cut point 3.0 mcg/L if BMI is less than or equal to 25 or 1.0 mcg/L if BMI is greater than 25) 5. 4-week stability on any psychotropic medications 6. 3-month stability on all hormone treatments 7. able and willing to provide informed consent to participant in the study and complete study protocol Exclusion Criteria: 1. history of a psychiatric disorder with substantial impact on functional status or quality of life (e.g., schizophrenia, schizoaffective disorder, bipolar, or other psychotic disorder) 2. history of neurologic disorder other than traumatic brain injury with substantial impact on the quality of life 3. other known cause for growth hormone deficiency (GHD) including history of childhood onset GHD, hypothalamic/pituitary disease, history of brain radiation, or genetic mutations known to lead to GHD 4. active suicidal ideation as determined by a score of 2 points or higher on the Columbia Suicide Severity Rating Scale 5. suicidal behavior in the past 6 months 6. contraindication to recombinant human growth hormone (rhGH) such as hypersensitivity to rhGH or any of the components of the supplied product 7. acute medical illness, active infection, cancer, or decompensated chronic medical illness (e.g., decompensated diabetes mellitus, congestive heart failure, chronic obstructive pulmonary disease) 8. evidence of substance use disorder in the past 6 months other than mild alcohol or cannabis use disorder diagnosed by clinician at time of screening. 9. urine toxicology evidence of illicit drug use (excluding cannabis) within the past 90 days prior to screening 10. BMI \> 35 or body weight \> 350 lbs 11. abnormal pituitary anatomy documented by an MRI using a Sella protocol 12. women who are pregnant or of child-bearing potential who are unable/unwilling to use one of the following barrier contraceptives: condoms, diaphragm, cervical cap, or intrauterine device 13. current use of the following: growth hormone, estrogen or estrogen-like dietary supplements, hormonal contraceptives, progestin, insulin growth factor 1 (IGF-1), or chronic glucocorticoid use in supraphysiologic doses 15\) currently enrolled in any other interventional drug trials unless prior approval is provided by the study chairs and the study sponsor