There are only two significant adverse reactions related to treatment with these radiopharmaceuticals. Myelosuppression is expected from irradiation of the marrow by beta particles localized in the bone which surrounds the marrow. The resulting decrease in leukocyte and platelet counts may not even result in leuko-penia and thrombocyopenia if the patient has a normal pretreatment leukocyte and platelet count and no evidence of DIC. The drop in leukocytes and platelets is usually in the range of 30% to 50% of the preinfusion count with these radio-pharmaceuticals. The nadir is between four and six weeks, and recovery occurs by eight to twelve weeks; both nadir and recovery may be at the earlier end of this range with the more short-lived radionuclides.
The flare phenomenon, an increase in pain in the sites being treated, is the other side effect. This is usually seen within 72 hours of administration, lasts a few days at most, and occurs in from about 5% to 60% of patients, depending, among other issues, on the degree of carefulness of follow-up, the asking of leading questions about pain, and the actual definition of the flare phenomenon employed. For example, a patient may assume that one day after infusion he is capable of more activity, tries to perform an act that is painful, and thus reports increased pain. This area has not been carefully studied.
Was this article helpful?