Carbamazepine is a therapeutic anticonvulsant, used to manage pain. We often use it to treat trigeminal and post-herpes zoster neuralgias. Interstitial pneumonitis (IP) is a known adverse consequence of using carbamazepine, with bronchiolitis obliterans and organizing pneumonitis. (BOOP) drug-induced IP as typical examples. Here we described a patient with post-herpes zoster neuralgia, who suffered from drug-induced acute IP that differed from cases typically induced by carbamazepine.