Infantile hemangiomas are proliferative vascular disorders that occur in the pediatric airway, potentially causing airway narrowing and respiratory stress. It appears in 1 out 10 children, more frequently in girls. Hemangiomas are benign tumours that usually appear on the head or neck but may also occur in deep organs. Until recently, the most common medical therapy used was high-dose systemic corticosteroids, which often resulted in significant adverse effects (hypertension, irritability, and Cushing-like conditions). In 2008, propranolol, which was used for treating cardiovascular diseases, was accidentally found to be successful in the treatment of intractable diffuse lymphangiomatosis. Propranolol apparently causes down-regulation of the Raf mutagenactivated protein kinase-signalling pathway, with reduced expression of vascular endothelial growth factor. Propranolol inhibits lymphangiogenesis and reduces lymphatic malformation growth by inhibition of vascular endothelial growth factor. It could have a beneficial effect on lymphatic malformation and in diffuse lymphangiomatosis, and may exert its effects on growing hemangiomas by three different molecular mechanisms: vasodilation, inhibition of angiogenesis and induction of apoptosis. This is a review of the pharmacology of propranolol as it relates to the treatment of hemangiomas.
KEYWORDS:
hemangiomas; infants; propranolol