Metformin Hydrochloride in Affecting Cytokines and Exosomes in Patients With Head and Neck Cancer

Inclusion Criteria:

* Subjects with a diagnosis of head and neck cancer biopsy proven, and who are candidates for radiation therapy
* All subjects must be able to comprehend and sign a written informed consent document.

Exclusion Criteria:

* Subjects who are pregnant or may become pregnant during metformin administration; pregnancy testing will be done in conjunction with preradiation protocols
* Subjects on metformin for any reason during the preceding 4 weeks
* Diabetic subjects are eligible if they are not taking metformin or insulin
* Subjects who have received iodinated contrast dye must wait 12 hours prior to starting Metformin. If a CT scan with contrast is scheduled after screening and consent, the metformin cannot be taken until after the CT with contrast has been completed and they have waited 12 hours.
* Patients with plasma creatinine level greater than 1.3 mg/dL
* Patients with plasma bicarbonate less than 22 mEq/L or history of lactic or any other metabolic acidosis
* Patients with history of congestive heart failure
* Patients with myocardial ischemia or peripheral muscle ischemia
* Patients with sepsis or severe infection
* Patients with history of lung disease currently requiring any supplemental oxygen treatment
* Patients scheduled for radiation less than 6 days from enrollment
* Patients with history of hepatic dysfunction or hepatic disease and abnormal liver function tests; patients who have a history of hepatic dysfunction or hepatic disease and normal liver function tests will be eligible to participate
* Patients with a current history (in the past 30 days) of heaving drinking which is defined in accordance with CDC definition as more than 8 drinks per week for women and more than 15 drinks per week for men. A standard drink contains .6 ounces of pure alcohol. Generally, this amount of pure alcohol is found in 12-ounces of beer, 8-ounces of malt liquor, 5-ounces of wine, 1.5-ounces or a "shot" of 80-proof distilled spirits or liquor (e.g., gin, rum, vodka, or whiskey). While on study, patients should limit their alcohol consumption to no more than 8 drinks per week for women and no more than 15 drinks per week for men. Patients who feel they cannot comply with this recommendation are not eligible".
* All medications are permitted except those that are contraindicated with metformin under current Food and Drug Administration (FDA) recommendations