AbstractAqueous extracts of leaves, rind, fruit pulp and flowers of Hylocereus undatus were studied for their wound healing properties. Wound healing effects were studied on incision (skin breaking strength), excision (percent wound contraction) and the nature of wound granulation tissues, which were removed on day 7 and the collagen, hexosamine, total proteins and DNA contents were determined, in addition to the rates of wound contraction and the period of epithelialization. In streptozotocin diabetic rats, where healing is delayed, topical applications of H. undatus produced increases in hydroxyproline, tensile strength, total proteins, DNA collagen content and better epithelization thereby facilitating healing. H. undatus had no hypoglycemic activity. Copyright © 2005 John Wiley & Sons, Ltd.