The goal of this pilot randomized controlled trial is to understand whether we can successfully conduct a larger definitive clinical trial in the future. The current pilot study will test various aspects of the larger trial and help us improve its design if needed. The investigators are mainly interested in knowing whether they can (1) recruit enough patients, (2) administer the intervention, and (3) collect all the data needed from patients. The definitive randomized controlled trial will assess if dexamethasone is superior to placebo for treating children and youth hospitalized with orbital cellulitis.

This is a double-blinded, placebo-controlled, internal pilot randomized controlled trial, with two parallel groups with a 1:1 allocation ratio, at The Hospital for Sick Children (Toronto, ON) and Stollery Children's Hospital (Edmonton, AB).The purpose of the study is to determine the feasibility of a definitive randomized controlled trial, which will determine whether IV dexamethasone 0.3 mg/kg after randomization and 24 hours later (2 doses total) is superior to placebo for children and youth hospitalized with orbital cellulitis.

Children and youth (n=30) hospitalized with orbital cellulitis will be randomized to receive IV dexamethasone 0.3 mg/kg (first dose after randomization, second dose 24 hours later) or placebo. The primary feasibility outcome of this pilot trial is recruitment rate. Secondary feasibility outcomes include (a) intervention fidelity, (b) completion of definitive trial primary, and (c) completion of definitive trial secondary outcomes.

Inclusion Criteria:

1. Age 2.00 months -17.99 years (prior to 18th birthday)
2. Confirmed or suspected diagnosis of orbital cellulitis as determined by the attending physician, medical team, and/or delegate's clinical judgement, based on one or more features of orbital cellulitis (i.e., ophthalmoplegia, pain and/or limitation with extraocular movements, chemosis, blurred vision, eye swollen shut, and/or proptosis).
3. Scheduled to be admitted or admitted to hospital for less than 36 hours.
4. Informed consent provided in accordance with institutional policies

Exclusion Criteria:

1. Transferred directly from outside hospital inpatient setting to a participating hospital site's inpatient setting with over 36 hours having passed since admission to outside hospital. If within 36 hours, patient is eligible.
2. Treatment with IV or PO systemic corticosteroids within 1 week of presentation
3. Recent hospital admission for orbital cellulitis within 1 week of presentation
4. Current systemic fungal infection
5. Contraindication for dexamethasone or components of dexamethasone IV formulation
6. Clinically relevant varicella exposure in the previous 21 days
7. Previous enrollment in this study
8. No telephone/mobile/email
9. Poor mastery of English, or medical interpreter not available for languages other than English