Intravenous injection of glucose blocking agents immediately before UHF are essential and have to be given quickly through a vein or an intravenous line. The blocking agents consist of cystine and oxidised glutathione and other similar forms of amino acids in their fully oxidised state. They carry a lot of oxygen with them, they look like glucose to the cancer cell and are therefore rapidly absorbed by them immediately the UHF radiation commences. The glucose is “burnt” by the blocking agent's oxygen and the cancer cell dies.