Would you like a topical medication that is difficult for an animal to lick off or that will adhere to a mucosal surface?
You can prescribe a medicated “polyox bandage” or “mucosal bandage”. When moistened, this medicated preparation will adhere to a wound or mucosal surface, thereby providing a protective barrier and increasing the contact between the medication and the affected area.
Wound and Incision Care - Prevent Licking
A common problem encountered by veterinarians and animal owners is preventing an animal from licking an incision or licking medication from the area to which it has been applied. In addition to injury to the wound, pharmacists and veterinarians must consider the consequences of internal consumption of an external preparation. To prevent an animal from licking, a medication can be compounded to contain an extremely bitter substance. Choices include diphenhydramine, quinine, or the non-therapeutic ingredient sucrose octaacetate. Sucrose octaacetate can be added at 1% to 5% to any topical dosage form and the bitterness usually prevents the animal from repeated licking of the area of application. Another way to protect a medicated area from licking is to incorporate the needed medication into CAP (Cellulose Acetate Hydrogen Phthlate) solution. Since CAP solution does not dissolve in an acidic pH, the animal’s saliva does not remove it from the skin. CAP solution can also be sprayed directly onto a wound or over stitches to protect them.
Phenytoin/Lidocaine Poly-Ox Bandage Used to Treat Leg Wound
Problem: Twenty-four hours after an automobile accident, an eight-month old female pit bull presented with a leg injury that appeared as if it would have difficulty healing. The dog had been hit by an automobile, which had scraped a hole in the right front leg. The wound, which extended from the elbow to the carpus, was approximately 3/4" to 1” wide.
Treatment: The tissue of the leg was stabilized using tension-relieving sutures. Because the veterinarian had prior successful experiences with other cases involving wound care, she requested we compound a topical preparation consisting of 2% phenytoin and 2% lidocaine in a methylcellulose/polyoxyethylene (poly-ox) bandage for the dog. The animal underwent hydrotherapy twice daily and the compounded medication was applied just before bandaging was secured.
Outcome: The wound was completely healed after 2 months of therapy and the animal has full use of her leg with no visible ill effects. According to the veterinarian, the animal healed much quicker than usual due to the increased contact time of the medications and she was satisfied with the treatment process.
We have also used this compound with the same positive success on a degloved feline after its paw had been caught in a fence overnight.
Randy S. Carr, R.Ph., FIACP & Pamela Doskey, D.V.M.
Therapy for Severe Chemical Burns
by Barbara Espe, D.V.M., North Dakota
In April 1998, I was called to euthanize a 1 1/2 year old female miniature schnauzer that had been burned with hot water from the bath tub and washed in Woolite® 3-4 weeks earlier. The full thickness burns involved about 80% of the skin on the dorsal trunk from neck to tail and elbows to midthigh. The owners were using aloe vera to treat the burns and she had a severe infection, was emaciated (5 lb.) and had not eaten for one week. Since she had survived so long without treatment, I had the owners sign ownership over to me and I contacted the Central Dakota Humane Society. They agreed to take on this project despite the many hours of labor and the potential cost. The dog was immediately given an analgesic and antibiotics.
I literally stopped at the pharmacy with the dog so the compounding pharmacist could see what we were up against. At the pharmacist’s suggestion, a Poly-Ox bandage containing phenytoin base 2% and misoprostol 0.002% was compounded and applied in a layered manner. Telfa® pads were used to cover the wound, and a T-shirt was put on to protect the bandages. The dog started eating canned food that night and in several days she was eating four large cans of food daily. In addition to the Poly-Ox bandage, she remained on Cefadrops® and Rimadyl®. She seemed to be uncomfortable and analgesics did not appear to control her pain. The powder was returned to the pharmacy and lidocaine 2% was added. Although this helped somewhat, the dog was becoming non-compliant at the time of her dressing changes. The compound was again modified to contain bupivacaine 0.2% to obtain an extended analgesic effect. This was a significant improvement and therapy continued for several months. As healing occurred, the dog began to experience itching in the regranulated skin and wound areas. Diphenhydramine was given orally along with the Rimadyl® and we began rubbing her stretched skin with Emu oil to keep it moist. Shortly thereafter, the dog “became a schnauzer again.” Her activity level has increased greatly and we anticipate a complete recovery.
When I began treating this dog, I thought that skin grafting would be necessary. Due to the success of this therapy, no grafting will be needed. However, I don’t expect hair regrowth and the epithelium will remain scarred and easily bruised.