The purpose of this study is to decrease the rate of visits to the Emergency Department (ED) and Acute Care Clinics (ACC) for dehydration for head & neck (H&N) and esophageal cancer patients that are given Gatorade while receiving radiation therapy with or without chemotherapy.

Among patients with cancer of the H&N or esophagus, complications related to dehydration are fairly common, and can result in requiring IV fluid support in an ACC setting, ED or even inpatient admission. By instructing participants to drink a reasonable amount of a common electrolyte-rich energy drink from the initiation of treatment through its completion, the hypothesis will be tested that this inexpensive and easily administered preventative strategy can significantly decrease the rate of ACC and ED visits.

The objectives of this study are to decrease the frequency of ACC visits during the course of radiation therapy and decrease the frequency of ED visits during the course of radiation therapy. The study team also seeks to decrease the incidence of orthostatic vital signs during the course of radiation therapy and decrease the number of days of missed treatments due to radiation toxicity during the course of radiation therapy.

In the pilot cohort, participants will be given Gatorade G2 to drink daily during the course of radiation, along with standard of care nutritional support from dietitians. The randomized Phase 2 cohort has two study groups. Group 1 will receive standard of care nutritional support. Group 2 will receive standard of care nutritional support plus the study agent, Gatorade G2.

Inclusion Criteria:

- Subjects must have histologically confirmed primary invasive cancer of the H&N (Nasopharynx/Nasal Cavity, Oral cavity, Oropharynx, Larynx, Hypopharynx) or Esophagus.

Histologies: squamous cell carcinoma, adenocarcinoma, adenoid cystic carcinoma, sinonasal undifferentiated carcinoma Stages: Any stage that necessitates radiation therapy (either definitive, neoadjuvant or adjuvant) as per standard practice guidelines (NCCN, ASTRO)

• Subjects must have received no prior radiation therapy to the head, neck, thorax or abdomen in the last 1 year (with the exception of scalp squamous cell or basal cell carcinoma.
• ECOG Performance status 0-2.
• Life expectancy of ≥ 3 months, in the opinion of and as documented by the investigator.
• Subjects must have organ and marrow function based on lab values deemed acceptable to proceed with radiation therapy. No additional or specific lab value cutoffs are required for this protocol given the nature of the intervention. General guidelines are provided below.
• Hemoglobin ≥ 7 g/dl
• Absolute neutrophil count ≥ 500/mcL
• Platelet count ≥ 50,000/mcL
• Total bilirubin within normal institutional limits
• Subjects must have the ability to understand and the willingness to sign a written informed consent document.
• HIV-positive subjects on combination antiretroviral therapy are eligible.

Exclusion Criteria:

The presence of any of the following will exclude a subject from study enrollment.

• Prior radiation therapy to the head, neck, thorax or abdomen in the last year, with the exception of scalp squamous cell or basal cell carcinoma.
• Patients with active, uncontrolled, symptomatic volume overload congestive heart failure.