Evaluation of LHP® (1% hydrogen peroxide) cream versus petrolatum and untreated controls in open wounds in healthy horses: a randomized, blinded control study.

BACKGROUND: Treatment and protection of wounds in horses can be challenging; protecting bandages may be difficult to apply on the proximal extremities and the body. Unprotected wounds carry an increased risk of bacterial contamination and subsequent infection which can lead to delayed wound healing. Topical treatment with antimicrobials is one possibility to prevent bacterial colonization or infection, but the frequent use of antimicrobials ultimately leads to development of bacterial resistance which is an increasing concern in both human and veterinary medicine.

METHODS: Standardized wounds were created in 10 Standardbred mares. Three wounds were made in each horse. Two wounds were randomly treated with LHP® or petrolatum and the third wound served as untreated control. All wounds were assessed daily until complete epithelization. Protocol data were recorded on day 2, 6, 11, 16, 21 and 28. Data included clinical scores for inflammation and healing, photoplanimetry for calculating wound areas and swab cytology to assess bacterial colonization and inflammation. Bacterial cultures were obtained on day 2, 6 and 16.

RESULTS: Mean time to complete healing for LHP® treated wounds was 32 days (95%CI=26.9-37.7). Mean time to complete healing for petrolatum and untreated control wounds were 41.6 days (95%CI=36.2-47.0) and 44.0 days (95%CI=38.6-49.4) respectively. Wound healing occurred significantly faster in LHP® wounds compared to both petrolatum (p=0.0004) and untreated controls (p<0.0001). There was no significant difference in time for healing between petrolatum and untreated controls. Total scores for bacteria and neutrophils were significantly (p<0.0001) lower for LHP® treated wounds compared to petrolatum from day 16 and onwards. Staphylococcus aureus and Streptococcus zooepidemicus were only found in cultures from petrolatum treated wounds and untreated controls.

CONCLUSIONS: Treatment with LHP® reduced bacterial colonization and was associated with earlier complete wound healing. LHP® cream appears to be safe and effective for topical wound treatment or wound protection.