Cytotoxic drugs and hyperglycaemia

Some cytotoxic drugs can cause hyperglycaemia; these include cancer chemotherapy (eg docetaxel, cyclophosphamide, L-asparaginase, vorinostat) and targeted anticancer drugs (eg tyrosine kinase inhibitors, epidermal growth factor receptor inhibitors). Glucocorticoids (eg dexamethasone) are often used in treatment regimens for cancer or for prevention of cytotoxic-induced nausea and vomiting, and can cause significant hyperglycaemia; see Glucocorticoid-induced hyperglycaemia.

If drug-induced hyperglycaemia develops, the patient’s prognosis should be considered when planning glycaemic treatment targets (see Glycaemic targets for adults with type 2 diabetes) and antihyperglycaemic drug treatment.

Many cytotoxic treatments are given cyclically, so antihyperglycaemic treatment should be targeted to the appropriate pattern for the individual patient (eg insulin might only be given on days one to four of a treatment cycle, corresponding to the days of dexamethasone use). The antihyperglycaemic dosage needs to be adjusted whenever the cytotoxic drug or glucocorticoid causing hyperglycaemia is started or stopped.

Ideally, all patients with type 2 diabetes should be taught to self-monitor blood glucose concentrations (if not already self-monitoring) before starting cytotoxic treatment that can cause hyperglycaemia. See information on self-monitoring blood glucose concentrations in adults with type 2 diabetes.