The purpose of this study was to evaluate the effect on fibroblast proliferation of hydrophilic particles isolated from six commercial hydrocolloid dressings. The hydrophobic adhesive matrix of six hydrocolloid dressings was removed using a reflux extraction method with an organic solvent (xylene). The remaining hydrophilic particles were dissolved in complete cell growth medium containing 10% (v/v) foetal calf serum and added to confluent human dermal fibroblasts grown in monolayer in final concentrations of 0.1 and 0.01% (w/v). Control cells received growth medium alone. The fibroblasts were incubated with the hydrophilic particles and the thymidine analogue 5-bromo-2'-deoxyuridine (BrdU) for 24 hours. The incorporation of BrdU into DNA was used as a measure of cell proliferation and determined using an ELISA kit. The results were expressed in percentage of control-treated wells and analysed using analysis of variance. Apart from Comfeel Plus, the hydrophilic particles of hydrocolloid dressings significantly inhibited fibroblast proliferation at 0.1% compared to control-treated fibroblasts (p < 0.05).