Treatment of intercostal neuralgia with 10 per cent ammonium sulfate

Intercostal nerves were injected with 10 per cent annomium sulfate in 41 patients (52 total sets of injections) for management of intercostal neuralgia from radical mastectomy (six blocks), thoracotomy (20 blocks), or unknown etiology (26 blocks). Five patients failed to return for follow-up evaluation and could not be located. Sixty per cent (28/47) of the treatments produced complete or nearly complete (excellent) relief of pain. Excellent pain relief persisted for more than 20 days after 22 treatments and for more than 90 days after seven treatments. Postblock neuritis never occurred. We conclude that intercostal nerve block with 10 per cent ammonium sulfate effectively relieves intercostal neuralgia and is not associated with postblock neuritis. We therefore believe that ammonium sulfate nerve blocks should be administered for treatment of intercostal neuralgia before phenol or alcohol nerve blocks or a surgical procedure.