Background Multiple studies have demonstrated thalidomide’s efficacy in numerous indications. Its use is controversial in the adult population, and in paediatrics the lack of experience makes it even more debatable.

Purpose To describe the case of a paediatric patient with recurrent aphthous stomatitis (RAS) resistant to the usual treatments and evaluate the efficacy/safety of the use of thalidomide (off-label).

Material and methods Retrospective observational study of a paediatric patient with RAS who does not respond to conventional treatments (oral treatments: prednisone 30 mg q.d., colchicine 0.5 mg q.d. and topical treatments: viscous lidocaine 2% t.i.d. and clobetasol propionate t.i.d.). Treatment protocol: ascending doses of thalidomide from 50 mg q.d. to 50 mg t.i.d. (oral suspension). Variables studied: population group, clinical situation, treatment possibilities for RAS and uses of thalidomide in children. The information was obtained from a review of the medical record and an exhaustive bibliographic search.

Results The presence of oral ulcers compromised the patient’s life quality and, due to the ineffectiveness of conventional treatments, with prior legal guardians’ authorisation, treatment with thalidomide was started. The aphasic episodes decreased in frequency of appearance and severity. The observed adverse effects were drowsiness, hand tremor and pain in the extremities. After 15 months of successful treatment, neutropaenia (0.9 × 10.3/μL, reference values 2.2–7.5 × 10.3/μL) triggered its discontinuation. After 4 months, the patient recovered from the adverse effects but the aphasic episodes continued, so treatment with colchicine 0.5 mg/24 hour and prednisone was started during acute episodes.

Conclusion The use of thalidomide in RAS had an excellent result in the reduction of the oral ulcers, however the development of adverse effects lead to the immediate suspension of the treatment. A strict and periodic monitoring of the patients becomes crucial in the paediatric population with this treatment.

Reference and/or Acknowledgements 1. Yang CS, Kim C, Antaya RJ. Review of thalidomide use in the paediatric population. J Am Acad Dermatol2015;72:703–711.

No conflict of interest