Study of Efficacy and Safety of Gabapentin to Reduce the Need for Strong Opioid Use in Head and Neck Cancer Patients.

Inclusion Criteria: * Histologically confirmed squamous cell carcinoma of the head and neck region, generally cancer of the oral cavity, pharynx and larynx. Cancer of the nasal cavity, nasopharynx, paranasal sinuses, parotid gland, or a T1-2N0M0 of the glottis are excluded. * Primary cancer eligible for primary or adjuvant radiotherapy with or without systemic treatment, with curative intent * TNM stage I to IVb, without distant metastases * Patients should require the intake of at least a weak opioid (inclusion starting at prescription/intake of at least a step 2 drug (e.g. a step 2 or step 3 analgesic; if a physician would decide to skip step 2) according to the WHO pain ladder) * Patients should be 18 or older at the time of enrolment * Patients should be able to adequately communicate in Dutch or French Exclusion Criteria: * Patients younger than 18 years at the time of enrolment * Patients with cancer of the nasal cavity, nasopharynx, paranasal sinuses, parotid glands, or a T1-2N0M0 of the glottis * Pregnant or lactating women (Non-pregnancy must be confirmed before the first administration by use of a urine pregnancy test. Any positive urine pregnancy test must be confirmed via a serum β-HCG test). * Patients presenting with another non-cured cancer (e.g. PSA or CEA not within normal range as determined by the treating physician) * Patients with a prior history of cancer, with or without radio(chemo)therapy, diagnosed within the last 5 years * Patients who report pos…