Inclusion Criteria:  Histologically proven cancer of the head and neck cancer Locally advanced non-metastatic disease (T3N0M0, T4N0M0, T1-4N1-3M0) Planned primary or adjuvant radiation or chemoradiation therapy Willing and able to provide informed consent ECOG PS 0-2 Age ≥ 21 years English speaking  Exclusion Criteria:  Currently on gabapentin or ketamine Prior non-tolerance of gabapentin or ketamine Unable to administer ketamine intranasally due to anatomical restrictions History of seizure disorder History of schizophrenia History of increased intracranial pressure Glomerular filtration rate <30 mL/min/1.73 m2