Dexamethasone versus placebo for patients with cellulitis

Plain English summary of protocol

Background and study aims
Cellulitis is a common bacterial skin infection. Over 300,000 people attend emergency departments in the UK each year with cellulitis. Antibiotic treatment is always recommended to kill the bacteria causing infection but does not always improve symptoms. Symptoms often get worse after starting antibiotics, with pain and swelling increasing in the first few days. Around one-fifth of people see a doctor again for further treatment. There is no evidence that giving out more antibiotics improves symptoms and using excess antibiotics will reduce their effectiveness for everyone (antibiotic resistance). Corticosteroid (“steroid”) tablets have been tried as an add-on treatment in a few small studies to reduce swelling, redness and pain. Results have been promising but the studies have been small and more research is needed to find out if steroid tablets work in cellulitis before advising clinicians to routinely use them.
This is a large study to see if prescribing steroid tablets alongside antibiotics improves symptoms and reduces the need for further antibiotics and healthcare visits for patients with cellulitis.

Who can participate?
Patients aged 16 years old or over who come to an NHS emergency or urgent care department with cellulitis.

What does the study involve?
After consent, participants will be put into one of two groups at random. One group will receive steroid (dexamethasone) capsules to take for 2 days, the other group will receive placebo capsules. Both groups will also get the normal treatment for cellulitis (antibiotics and painkillers). Neither the participants nor the clinicians will know which group they are in. The researchers will ask participants about their pain twice a day for three days via electronic survey/text message or telephone call if preferred. They will telephone participants after 14 days to ask about lingering pain, antibiotic and painkiller use and any other healthcare use and after 90 days to see if they have had cellulitis again.

What are the possible benefits and risks of participating?
Dexamethasone is not usually used to treat patients with cellulitis. It is currently unknown whether taking dexamethasone on top of the usual treatments will help symptoms. The main benefit of taking part is to help us see whether this new treatment works and potentially improve care for patients in the future.

Dexamethasone is widely used for several illnesses, but like all medicines, it does have some possible side effects. This study uses low doses of dexamethasone for a short period, compared to the doses used for some other conditions. Dexamethasone is expected to be active shortly after taking it and wash out of the participant’s systems within a few days. Any side effects are also expected to last for a short period. Whilst the risk of side effects with short-term use appears low from previous studies, some of our participants may be at increased risk (e.g. diabetic patients, older patients and those taking non-steroidal anti-inflammatory drugs). A full assessment of these risks is outlined in the trial protocol (section 2.4.0.) and the site teams will be trained in assessing these risks during recruitment.

The PIS outlines the key side effects for participants. As part of the consent conversation, the site team will discuss possible side effects with the participant and answer any questions. There will be a particular focus on diabetic patients, pregnancy and breastfeeding.

Where is the study run from?
University of Exeter (UK)

When is the study starting and how long is it expected to run for?
January 2024 to December 2026

Who is funding the study?
National Institute for Health and Care Research (UK)

Who is the main contact?
DEXACELL@exeter.ac.uk

Contact information

Study information

Eligibility

Locations

Countries of recruitment

• United Kingdom
• England

Study participating centres

Results and Publications

Study outputs

Additional files

ISRCTN76873478_PROTOCOL_V4.0_20Nov24.pdf

Protocol file

ISRCTN76873478_PROTOCOL_V5.0_07Jan25.pdf

Protocol file

Editorial Notes

17/11/2025: The date of final enrolment was updated from 31/01/2026 to 10/11/2025. Total final enrolment added.
03/03/2025: The following changes were made to the trial record:
1. The recruitment start date was changed from 03/02/2025 to 28/02/2025.
2. The study participating centres University Hospital Lewisham, Northern General Hospital, Watford General Hospital, Milton Keynes University Hospital, Kings College Hospital.
14/02/2025: IPD sharing plan added.
28/01/2025: The following changes were made to the study record:
1. Protocol uploaded.
2. The exclusion criteria were updated.
3. Wexham Park Hospital and James Cook University Hospital were added to the study participating centres.
04/12/2024: The recruitment start date was changed from 01/11/2024 to 03/02/2025.
28/11/2024: The following changes were made to the study record:
1. Protocol uploaded.
2. The inclusion criteria were updated.
3. Leicester Royal Infirmary and John Radcliffe Hospital were added to the study participating centres.
06/11/2024: Internal review.
09/10/2024: ISRCTN received notification of combined HRA/MHRA approval for this trial on 09/10/2024.
20/08/2024: Study's existence confirmed by the HRA.