Direct Oral Challenge For Rapid Penicillin De-Labelling In Acute Admitted General Medical Patients

Skin prick testing was undertaken with Depo-Nisolone (Kenral) diluted to 2mg/ml which was positive. Since true allergy to methylprednisolone is rare, we dissected out the components of Depo-Nisolone and tested to macrogol (polyethylene glycol) 3350 (Movicol [Norgine]) and plain methylprednisolone (Solu-Medrol [Pfizer]). This revealed positive skin test to 0.1% macrogol 3350, negative test to 2mg/ml methylprednisolone. The patient was counselled on avoiding macrogol 3350 but cleared of corticosteroid allergy. Due to organizational difficulty in acquiring other polyethylene glycol (PEG) compounds we have been unable to extrapolate results to other size PEGs.