Topical amiloride ointment accelerates healing of mechanical skin ulcers in albino rabbits and patients

The present investigation was undertaken to explore the ulcer-healing property of 1% amiloride ointment on mechanically produced skin ulcers in albino rabbits and at donor site of patients requiring split skin graft. Four skin ulcers measuring 2 X 2 cm(2) (two on either side of the midline) were made 2 cm apart on the pre-shaved back of each anesthetized rabbit up to the depth of subcutaneous tissue. Ulcers on one side of the midline were treated with sterile soft paraffin and served as control, whereas those on the other side were treated with amiloride ointment. Each ulcer was observed for its size, slough formation, and any sign of irritation on alternate days, until healing was complete. Healing of ulcers was significantly (p<0.001) accelerated with amiloride ointment in terms of days required for complete healing, ulcer size, and area under the size-time curve. In each patient, the anterior thigh was used as donor site. Grafts were harvested from midline using Watson's modification of Humby's knife. Each site was divided into proximal and distal halves and was covered with either soft paraffin tulle serving as control or 1% amiloride tulle as test site and then dressed conventionally. Healing was evaluated visually on 10th postoperative day. Healing was significantly accelerated by amiloride tulle in terms of days required for complete healing (p<0.01), better quality of skin regenerated, leading to ease of removal of dressing with less of patient's discomfort, and hence more acceptability (p<0.01). No irritation or suppression of immunity was noticeable. Thus, topical amiloride may prove to be an inexpensive and better ulcer-healing agent with no apparent side effect. Inhibition of urokinase-type plasminogen activator and modulation of field strengths by amiloride seem to be responsible for this effect.