Background: Prior to receiving docetaxel-based chemotherapy patients often incorrectly take all or part of their steroid-premedication. The lack of standardised steroid-replacement strategies can lead to variability in care and delays in starting chemotherapy while nursing/pharmacy/physicians establish an individualized patient plan, which can use up valuable chemotherapy chair time. A randomised controlled trial comparing a fixed-oral dose of dexamethasone and physician-directed replacement was performed. Methods: Patients who missed at least one dose of steroid-premedication were randomised to either standard replacement with dexamethasone 8mg orally or physician-directed replacement (any steroid, dose or route). The primary outcome was time from randomisation to starting docetaxel. Secondary outcomes included rates of acute and delayed hypersensitivity reactions, fluid retention and skin rashes. Results: Sixty patients were randomized. Most patients were enrolled during cycle 1 (47.5%) and cycle 2 (22%) of docetaxel. The most frequent total doses of dexamethasone omitted were 24 mg (27%), 12 mg (20%), and 8 mg (19%). There were 7 different replacement strategies used by physicians. The most frequently used strategies were: dexamethasone 8mg IV (34.5%), 12mg IV (17.2%) and 20mg IV (13.8%). Patients in the fixed-dose arm received docetaxel earlier than patients in the physician-choice arm, at a median of 47.5 and 61 minutes after randomization (mean = 62.2 vs 83.4 minutes) (p = 0.033). No significant difference in rates of acute (0 vs 2)/delayed allergic reactions (1 vs 0), fluid retention (2 vs 1), or skin rashes (1 vs 0) was observed between the fixed-dose and physician-choice arms respectively. Conclusions: This is the first randomised trial to compare steroid-replacement strategies in this patient population. Fixed-dose replacement with dexamethasone 8 mg PO should be the preferred standard of care, as it reduces both the time to starting docetaxel and treatment variability, with no apparent increase in toxicity. Clinical trial information: NCT02815319.