RT Journal Article SR Electronic T1 Iatrogenic Cushing’s syndrome due to drug interaction between glucocorticoids and the ritonavir or cobicistat containing HIV therapies JF Clinical Medicine JO Clin Med FD Royal College of Physicians SP 412 OP 418 DO 10.7861/clinmedicine.16-5-412 VO 16 IS 5 A1 Emilie R Elliot A1 Aikaterini Theodoraki A1 Lakshmi R Jain A1 Neal J Marshall A1 Marta Boffito A1 Stephanie E Baldeweg A1 Laura J Waters YR 2016 UL http://www.rcpjournals.org/content/16/5/412.abstract AB Ritonavir and cobicistat, used as pharmacokinetic enhancers in combination with some antiretrovirals (ARVs) for the treatment of HIV, are potent inhibitors of the CYP3A4 isoenzyme. Most glucocorticoids are metabolised via the CYP3A4 pathway and iatrogenic Cushing’s syndrome (ICS), with possible secondary adrenal insufficiency (SAI), is a recognised complication following co-administration with ritonavir or cobicistat. A structured approach for identifying and managing potentially affected individuals has not been established.We systematically identified patients with ICS/SAI and found substantial heterogeneity in clinical practice across three large London HIV centres. While this significant drug interaction and its complications are now well-recognised, it is apparent that there is no standardised approach to management or guidance for the general physician. Here we describe the management of ICS/SAI in our current practice, review the available evidence and suggest practice recommendations.