Somatostatin analogue is useful in carcinoid crisis for symptom control. Optimal dosing of somatostatin analogues for carcinoid symptoms is not known. This case highlighted management issues using combination short-acting octreotide infusion with long-acting lanreotide during carcinoid crisis. The patient had left lung neuroendocrine tumour that metastasized to his liver and bone, post left lobectomy. Due to extensive metastasis to the liver causing recurrent carcinoid crisis, he required shorter interval long-acting lanreotide with continuous infusion of short-acting octreotide, which led to transient diabetes insipidus. Symptoms resolved with discontinuation of treatment. Somatostatin analogues, especially in combination, may inhibit the posterior pituitary resulting in diabetes insipidus. Prompt withdrawal of short-acting somatostatin analogue and initiation of desmopressin can reverse the complication. It is important to recognize this complication with combination of octreotide and lanreotide injections to avoid serious complications.