The objective of this study was to determine the toxicity and efficacy of the current phase II chemoradiation protocol. Stage III or IV locally advanced head and neck squamous cell carcinomas arising from the oral cavity, hypopharynx, oropharynx, nasopharynx, paranasal sinuses, or larynx were treated using hyperfractionated radiation (74.4 Gy at twice-daily fractions of 1.2 Gy) in combination with a 5-fluorouracil, cisplatin, paclitaxel regimen, and an amifostine infusion. Thirty-five of 36 eligible patients were evaluable. The overall survival (OVS) was 88%, 82%, and 66% at 1, 2, and 3 years respectively. Twenty-five patients (71%) had a complete response, which was maintained in 20 (57%) patients until last follow up or death. Disease-free survival (DFS) of the complete responders was 92% at 1 year and 77% at 2 years and 3 years, respectively. Percutaneous endoscopic gastrostomy dependency lasted for a median of 7 months. Grade 3 and 4 mucositis occurred in 23 and 3 patients, respectively. Comparison with a similar study (A-2) that did not include amifostine showed no significant benefit to the addition of amifostine in these patients. A locoregional control benefit should be confirmed in a prospective, randomized trial. Alternative amifostine delivery methods should be investigated.