Capecitabine-induced headache responding to diltiazem

Headaches have been reported as a potential side effect of capecitabine therapy. However, severe limiting headaches are rarely experienced in this setting and no known therapy has been described for such a serious side effect.

We report the case of a patient treated with capecitabine and radiation for rectal adenocarcinoma. The patient developed grade 3 capecitabine-induced headache. A cause-effect relationship to capecitabine was suggested due to resolution of headache with capecitabine withdrawal and reappearance with capecitabine rechallenge. The patient's headache resolved with diltiazem therapy and she was able to complete capecitabine and radiation therapy without further adverse events.

Capecitabine and 5-fluorouracil (5-FU) are known vasospasm inducers. We hypothesize that capecitabine-induced headache is vascular in nature. This likely explains the noted response to a calcium channel blocker (CCB), namely diltiazem. CCBs should be considered in the treatment of 5-FU or capecitabine-induced headaches.