Inclusion Criteria:
* Patients with a diagnosis of advanced non-small cell lung cancer
* Presence of anorexia, defined as =\< 37 points on FAACT A/CS domain (on a 0 to 48-point scale in which 0 = worst possible anorexia/cachexia)
* Patients with a history of either: \>= 5% of weight loss for body mass index (BMI) \>= 20 kg/m\^2 or \>= 2% of weight loss for BMI \< 20 kg/m\^2, over a period of 1 year
* Patients must be willing to keep a daily medication diary and engage in telephone follow up with research staff
* Patients must have telephone access to allow contact by the research staff
* Adequate hepatic function, defined as aspartate transaminase (AST) and alanine transaminase (ALT) levels =\< 5 x upper limit of normal (ULN)
* Life expectancy of \>= 6 months
Exclusion Criteria:
* Major contraindication to anamorelin i.e. hypersensitivity
* BMI \>= 28 kg/m\^2
* Inability to complete the baseline assessment forms or to understand the recommendations for participation in the study
* Pregnant or lactating women. Women of childbearing age not on birth control. For inclusion in the study, a negative pregnancy test for women of childbearing potential, as defined by intact uterus and at least one ovary, and a history of menses within the last 12 months is necessary. Pregnancy test is to be performed no greater than 14 days prior to consent in study. In cases of women with elevated b-human chorionic gonadotropin (HCG), these candidates will be eligible to participate so long as the level of b-HCG is not consistent with pregnancy. Women of childbearing potential must be on or use contraception during the study period. Their male partners must also use contraception (condom) or maintain abstinence. Birth control specifications: Women who are able to become pregnant must use birth control during the study and for 30 days after the last anamorelin dose. Acceptable forms of birth control include barrier methods (such as condom or diaphragm) with spermicide
* Uncontrolled diabetes mellitus (fasting blood sugar \> 200 mg/dl) at screening
* Patients on drugs with strong CYP 3A4 inhibitors within the previous two weeks (ketoconazole, clarithromycin, itraconazole, nefazodone, telithromycin)
* Patients on drugs that may prolong the PR or QRS interval durations, such as any of the class I/sodium (Na+) channel blocking antiarrhythmic medications should be avoided (e.g. flecainide, procainamide, propafenone, quinidine)
* Patients currently on investigational therapies will be evaluated by the principal investigator (PI) on a case by case basis and study participation approval will be obtained from the treating oncologist
* Patient currently taking androgenic compounds (including but not limited to testosterone, testosterone-like agents, oxandrolone, megestrol acetate, methylphenidate, corticosteroids \[note: topical, inhaled, or oral corticosteroids taken for a short duration (=\< 5 consecutive days) after chemotherapy are acceptable\]), dronabinol or medical marijuana (medical cannabis) or any other prescription medication or off-label products intended to increase appetite or treat unintentional weight loss
* Any relevant condition that would interfere with ability to participate in one-on-one interviews either in person or via telephone
