Skin injury and dermatitis are common complications following chemotherapy and radiation administration for cancer treatment. Symptomatic relief of these complications is limited to slow-acting therapies and often results in holding or modifying cancer therapy that may impact patient outcomes. The off-label use of oral high dose vitamin D3 has demonstrated rapid clinical improvement in skin inflammation and swelling in both chemotherapy and radiation-induced injury. Furthermore, vitamin D3 has been shown to downregulate pro-inflammatory pathways and cytokines, including NFkB, and CCL2, as well as CCL20, which are not only involved in tissue injury, but may confer resistance to cancer treatment. In this paper, we discuss 2 patients with acute radiation dermatitis and acute radiation recall dermatitis following chemotherapy who received 50 000 – 100 000 IU of oral high dose vitamin D3 with improvement in their symptoms. These findings may indicate the potential use of vitamin D as a therapeutic intervention and future target for studying skin healing following chemotherapy and/ or radiation-induced cutaneous toxicity.