A randomised controlled trial evaluating the efficacy of multi-wavelength photobiomodulation for providing anaesthesia in intradermal injections

INTERVENTION: What is the intervention A multi‐wavelength light‐emitting diode (LED) device (700–1100nm, spanning visible and near‐infrared light), applied to the skin to induce photobiomodulation‐based analgesia prior to intradermal injection. Who delivers it and their relevant expertise The device is applied and the procedure conducted by the site investigators (dermatology medical clinicians) at Westmead Hospital Dermatology Outpatient Clinic that have been trained in the use of the device. How it is delivered Face‐to‐face, individual (one‐on‐one), in‐person clinical procedure. The device is placed directly over a marked 1cm × 1cm site on the volar forearm. The participant will then receive an intradermal injection with a 30gauge needle with 0.1mL of 0.9% normal saline solution. The participant will then have a Telehealth phone call 1 week later to assess for any side effects. How often and for how long A single application per arm: the device is activated and held over the site for 60 seconds immediately before injection. Each participant receives this once on each forearm (one arm gets the intervention, the other the sham/control device) in a single study visit — i.e., 2 applications total (once per arm) within one session, of 60 seconds' duration each. No washout period is required as the previous device and injection will not have an effect on the other arm. The participant will then have a Telehealth phone call 1 week later to assess for any side effects. Where it is delivered Tertiary hospital setting: Dermatology Outpatient Clinic, Westmead Hospital, Sydney, Australia. Adherence As this is a single‐session, investigator‐administered procedure (not a self‐administered or take‐home intervention), adherence is ensured by di CONDITION: Anaesthesiology ‐ Pain management Pain; ; Pain Skin ‐ Normal skin development and function PRIMARY OUTCOME: Pain score using the NRS (0–10) at the time of injection of 0.1mL 0.9% sodium chloride into the intradermal plane.[Numeric Rating Scale (0‐10) Immediately following injection, during the single study visit.] Pain score using the Numeric Rating Scale (0–10) at the time of 30G hypodermic needle insertion[Numeric Rating Scale (0‐10) At time of needle insertion, during the single study visit] SECONDARY OUTCOME: Adverse events related to device application and injection site.[Survery/questionnaire to the participant ; ; They adverse events will be assessed and graded according to the Common Terminology Criteria for Adverse Events (CTCAE v6.0). ; ; Possible adverse reactions include skin pain, redness, swelling at the site of device aplication. From the study visit up to 1 week post‐application (assessed via telehealth follow‐up).] Pain/discomfort associated with device application itself[Numeric Rating Scale (0‐10) At end of the 60‐second device application, during the study visit.] INCLUSION CRITERIA: Aged 18 years or older, able to provide consent Able to use both forearms Normal skin overlying both forearms Able to verbalise and report pain