A transient worsening of pain occurs in approximately 30 to 40% of patients [4,20]. This typically occurs in the first few days after radiation therapy (RT), and the flare in pain generally lasts one to two days. Treatment with dexamethasone may reduce the frequency of a pain flare.
In a double-blind trial, 298 patients with painful bone metastases were randomly assigned either dexamethasone (8 mg daily for five days beginning one hour before a single dose of 8 Gy radiation) or placebo . The incidence of pain flare was decreased with dexamethasone compared with placebo (26 versus 35%, p = 0.05).