The September blog post entitled “Wound Cleaning – What to Have on Hand and What to Toss Out” discussed products for the cleaning of superficial wounds. This month’s blog post is a follow up to that and discusses some of the most commonly used over the counter and prescription wound ointments. Some of these topicals are supported by research and have shown to be effective at promoting wound healing, while others are either unsupported, ineffective, or can even be harmful to tissues. Wounds which are surgically closed with sutures do not typically require a topical antimicrobial ointment but we do commonly recommend topical s for treatment of open cuts, scrapes, and wounds. The best topical dressing is one that is water soluble, non drying, non irritating, and does not delay wound healing. Read on for descriptions of some of the more commonly used topical treatments and find out which are helping your horse and which may be damaging!
Triple Antibiotic ointment—(Neosporin, generic) This over the counter ointment contains three antibiotics (Neomycin, Polymixin B, Bacitracin) which work together to be more effective than any of those antibiotics work individually. Triple antibiotic ointment has been shown to be one of the most effective topical antibiotics in wound healing and is not irritating or damaging to healthy tissue. This ointment is safe to use on wounds including those on mucus membranes and around the eye and is safe (and effective!) for people as well.
Silver sufadiazine 1% (Ascend, SSD, Silvadene, Thermazene) This prescription medication is a water soluble, white ointment which was developed to use on burn patients and is safely used on humans, dogs, cats, and horses. It has a broad spectrum activity against a variety of bacteria including Pseudomonas species and some research has shown it to be effective against yeasts, fungi, and viruses as well. This product is safe and effective on many types of wounds and is safe for use around the eye and mucus membranes.
Hydrogels—(Vetericyn , NovaZo) Hydrogels are made of water, glycerin, and polymers and were designed to provide moisture to wounds. They provide a barrier against the external environment and debris and provide a moist environment for healing. They do not have antibacterial properties so will not be effective against an infected or contaminated wound. Hydrogels are available as a gel, or impregnated in a gauze or pad. One study in horses showed that a particular hydrogel (Solugel) showed no beneficial or adverse effect on healing of distal limb wounds and another study performed on hydrogel use in dogs showed similar results. Based on the literature, hydrogels are not likely to be harmful to wounds but there is little to support that they will do much to help improve the healing process.
Cut-Heal – This is an over the counter product which contains fish oil, sulfuric acid (battery acid), linseed oil, and turpentine. Turpentine and sulfuric acid are known skin irritants so products containing these substances are NOT recommended for use on wounds.
Nitrofurazone ointment – (Fura-zone, NFZ) This over the counter product is an ointment that most of us have in our medicine boxes, but is it safe and what is its best use? Research has shown that nitrofurazone is damaging to the healthy cells, prevents skin growth, and has minimal effect against bacteria and other microorganisms. In one study, when compared to other topicals including SSD and triple antibiotic ointment, nitrofurazone was associated with a significantly slower time for wound healing. Additionally, nitrofurazone is not safe to use around the eye and has been shown to be a carcinogen (tumor causing) in lab animals. As veterinarians, we commonly recommend using nitrofurazone (+/- Epsom salts and DMSO) for a sweat under a bandage to decrease swelling but we do NOT typically recommend its use for wounds. If you are using this ointment for any reason, always wear gloves and wash your hands thoroughly after handling.
Gee Whiz?!? Old Time Remedies
Medical grade Honey—Honey is an old time remedy that has been regaining favor in the medical community for its use on wounds. Research has shown that specific types of medical grade honey found around the world including several types in Australia, New Zealand, Scotland, and North Africa, can be effective in treating many species of bacteria including methicillin resistant Staphylococcus aureus. Honey works by changing the acidity and osmolality of the wound environment as well as containing phytochemicals that have yet to be identified. The manner in which the honey is harvested, the floral origin of the honey, and the type is extremely important in how effective it may be. Multiple animal studies have shown that honey has anti-inflammatory properties, stimulates new tissue growth, and promotes wound healing and can be effective on distal limb wounds in horses which are notoriously difficult to treat.
Scarlet Oil- (Red Kote) Scarlet oil has been used for decades by horse owner’s for wound management, but no controlled studies have been performed to evaluate its efficacy. Scarlet oil can cause painful inflammation and irritation to the skin causing many horses to object to treatment. Due to the lack of research and the known side effects, we do NOT recommend scarlet oil for applying to wounds.
This article contains just a short list of the countless products that are available to us as veterinarians and to you as the horse owner. There are hundreds of products available to you from your local feed store, tack shop, or equine catalog and trying to sort through the products and their ingredients to find the best one can be a daunting task. Keep in mind that some topical products contain a steroid ingredient such as cortisone or dexamethosone which are helpful with certain skin conditions but suppress healing of wounds (including corneal ulcers) and encourage infection which can have extremely negative consequences. Making sure that you understand the best use of wound therapies and medications is in the best interest of you and your horse. If you have any questions regarding the ingredients and safety of the topical wound treatments that you use, please call Woodside Equine Clinic to speak with one of our veterinarians!