Following reports of heparin use in burn treatment, an ethics-committee-approved prospective randomized study with controls compared results obtained using traditional usual burn treatment without heparin with results in similar patients similarly treated with heparin added topically. The subjects were 100 consecutive burn patients (age, 15-35 yr) with second-degree superficial and deep burns of 5-45% TBSA size. Two largely similar cohort groups, i.e. a control group (C) and a heparin group (H) with 50 subjects per group, were randomly treated, the main difference between the groups being that 13 C patients had burns of 35-45% extent vs. only one such patient in H (p < 0.01). The 50 C patients received traditional routine treatment, including topical antimicrobial cream, debridement, and, when needed, skin grafts in the early post-burn period. The 50 H patients, without topical cream, were additionally treated, starting on day 1 post-burn, with 200 IU/ml sodium aqueous heparin solution USP (heparin) dripped on the burn surfaces and inserted into the blisters 2-4 times a day for 1-2 days, and then only on burn surfaces for a total of 5-7 days, prior to skin grafting, when needed. Thereafter, C and H treatment was similar. It was found that the H patients complained of less pain and received less pain medicine than the C patients. H needed fewer dressings and oral antibiotics than C. Significantly less intravenous fluid was infused in H: 33.5 litres in 39 H patients vs. 65 litres in 41 C patients, i.e. nearly 50% less (p < 0.04). The 50 H patients had four skin graftings (8%), while the 50 C patients had 10 (20%). Five 5 C patients died (mortality, 10%). No H patients died. The number of days in hospital for H vs. C was significantly less (overall, p < 0.0001): 58% of H were discharged within 10 days vs. 6% of C; 82% of H were out in 20 days vs. 14% of C; 98% of H vs. 44% of C were out in 30 days; and while 100% of H were discharged by day 40, 56% of C required up to another 10 days. The burns in H patients healed on average in 15 days (maximum period 37 days) vs. an average of 25 days (maximum > 48 days) in C (p < 0.0006). Procedures and costs in H were much reduced compared with C. Photographs of the differences between H and C are presented for the sake of comparison. It is concluded that heparin applied topically for 5-7 days improved burn treatment: it reduced pain, pain medicine, dressings, and use of antibiotics; it significantly reduced IV fluids (p < 0.04), days in hospital (p < 0.0001), and healing time (p < 0.0006); and it reduced skin grafts, mortality, and costs.