RecruitingPhase 2Drug trialReversing External-beam Radiotherapy-associated Fibrosis Syndrome: an Interventional Bayesian Adaptive Randomized-controlled Orphan Drug Platform Trial for Orodental Sequelae (Reverse-fibrose)To find out if adding medication can help treat or prevent lymphedema and/or fibrosis related to radiation therapy, in survivors of head and neck cancer. Researchers will compare these drugs to find the most effective therapy for preventing or limiting these side effects.