Effects of L-carnosine and its zinc complex (Polaprezinc) on pressure ulcer healing

L-carnosine (CAR) is an endogenous dipeptide. We aimed to determine the effects of CAR and its zinc complex polaprezinc (PLZ) on pressure ulcer healing in institutionalized long-term care patients.

This study was a nonrandomized controlled trial with a maximum 4-week follow-up. Forty-two patients with stage II-IV pressure ulcers for 4 or more weeks were allocated to 1 of 3 groups in order of recruitment: the control group (n = 14) was untreated, the PLZ group (n = 10) orally received 150 mg/d PLZ (containing 116 mg CAR and 34 mg zinc), and the CAR group (n = 18) orally received 116 mg/d CAR. Pressure ulcer severity was measured weekly using the Pressure Ulcer Scale for Healing (PUSH) score.

At baseline, no significant differences were found among groups in demographic and nutrition parameters and pressure ulcer characteristics (severity, size, and staging). After 4 weeks, the rate of pressure ulcer healing, assessed by the mean weekly improvement in PUSH score, was significantly greater in the CAR (1.6 ± 0.2, P = .02) and PLZ groups (1.8 ± 0.2, P = .009) than in the control group (0.8 ± 0.2). The difference between the CAR and PLZ groups was not significant (P = .73). Actual dietary intakes over this period did not differ significantly among groups.

Our results suggest that CAR and PLZ may almost equally accelerate pressure ulcer healing during 4 weeks. The results need confirmation by randomized controlled trials with larger sample sizes.