Can Zinc Oxide Have An Impact On Wound Healing?
In a 1991 study, researchers found that using zinc oxide increased the degradation of collagen in necrotic wounds.5 In another recent study, zinc oxide was found to promote epithelialization of full thickness skin wounds by the activation of zinc-dependent MMPs, which facilitate keratinocyte migration. The study also demonstrated that zinc oxide augmented endogenous expression of insulin-like growth factor (IGF-1), which is fundamental in the production of granulation tissue.1
In a randomized, double-blind study of the efficacy of locally applied zinc oxide on the healing of leg ulcers, 37 geriatric patients (19 with arterial and 18 with venous leg ulcers) were treated with either a gauze compress medicated with zinc oxide or an identical compress without zinc oxide. The treatment was assessed from ulcer size measurements and the presence or absence of granulation, and ulcer debridement over a period of eight weeks. The zinc-treated patients (83 percent success rate) responded significantly better than the placebo-treated patients. Researchers found that infections and the deterioration of ulcers were less common in zinc oxide treated patients.6
In another animal study, reepithelialization was enhanced when zinc oxide was applied topically on partial-thickness wound in pigs with normal zinc status. The inflammatory reaction was diminished in zinc-treated wounds except when researchers applied a high zinc sulfate concentration.7
Researchers also assessed bacterial growth in full-thickness wounds and demonstrated a reduced rate of growth with topical zinc oxide but not in hyperglycemic diabetic rats. The antibacterial mechanism of zinc oxide was described to be more indirect (mediated via local defense systems) rather than being directly toxic to the bacteria.8 When one applies zinc on wounds, it not only corrects a local zinc deficit but also acts pharmacologically.
Getting Results With Zinc Oxide: A Few Case Studies
A 47-year-old type 2 diabetic patient presented to the office with a chronic grade 1-A (University of Texas Wound Classification System) ulceration that had been present on and off for over two years. After providing effective pressure relief and debridement, the patient was treated in the office and at home with zinc oxide. Within 14 days, the wound completely closed.
A 58-year-old type 2 diabetic presented with a chronic interdigital ulceration that had been present for over a year. The ulceration was present secondary to a contracted digit and neuropathy. The patient’s wound healing was extremely poor from both non-compliance and poorly controlled blood sugar. Given the inflammatory and chronic nature of the wound, we started daily zinc oxide treatments along with regualr wound care. In less than 14 days, the patient had complete epithelialization of the wound (see photos on pages 22 and 25).
A 63-year-old vascularly compromised diabetic type 2 patient presented to the office with a severe streptococcus infection throughout his entire left forefoot, resulting in significant skin loss dorsally and plantarly. A year earlier, the patient had a transmetatarsal amputation and a partial fifth ray amputation six months later on the left foot. After the patient had a brief hospital stay along with IV antibiotics, we began zinc oxide treatments immediately. We chose zinc because of its ease of use in the home and its excellent antiinflammatory and drying properties. Despite the patient’s poor vascular status and extremely poor home conditions, the patient used the zinc oxide faithfully and presented regularly for his in-office wound care, resulting in complete healing in a matter of three months.
A 51-year-old diabetic patient developed a severe pin tract infection following a routine K-wire removal after a simple digital arthroplasty. The pin tract infection resulted in a cellulitic sausage digit deformity. While in the hospital for IV antibiotics, a minor incision and drainage was performed. After the procedure, daily zinc oxide treatments were started, resulting in complete resolution of the sausage digit deformity.