Oral famotidine reduces the plasma level of soluble P-selectin in children with sickle cell disease.

Plasma histamine levels are increased in patients with sickle cell disease (SCD), potentially promoting endothelial P-selectin expression and vaso-occlusion via histamine type 2 (H2) receptors. We conducted a prospective, non-comparative, single-centre study to determine whether famotidine, a H2 receptor antagonist, reduces P-selectin expression in SCD children. The median plasma P-selectin level was significantly reduced after 29 days of oral famotidine (53.2 ng/mL [IQR: 46.7-63.4] vs. 69.9 ng/mL [IQR: 53.6-84.2], median difference -10.2 ng/mL [IQR: -21.8 to -2.7], p = 0.005) in 28 patients. No effect was observed on other adhesion molecules, inflammation or haemolysis markers, except decreased reticulocyte count. No adverse events deemed related to famotidine were observed. Randomized controlled trials are now needed to assess the efficacy of famotidine in preventing vaso-occlusion in SCD.