Shampoo therapy is often used in conjunction with medical therapy for various types of skin disorders including ectoparasites (mange, lice, fleas), allergic skin disease, bacterial skin infections (pyoderma), fungal skin problems (ringworm, Malassezia dermatitis), and other disorders such as seborrhea, dry skin,, etc. When used correctly shampoos can be used to prevent secondary skin problems, control odor and contribute to the comfort and cleanliness of the patient. Bathing also rehydrates the skin and contributes to better overall skin health.
The skin consists of layers of cells on top of each other and there is a cycle of cell migration from the deeper layers to the upper layers. As the cells are pushed towards the skin surface they undergo a process called keratinization . In this process the cells become cornified or dried out and eventually serve as protection against damage and dehydration for the cells beneath them. Ultimately, the skin cells are sloughed off as fine scale and are replaced. This cycle repeats itself over and over again. There are primary diseases of the skin known as primary keratinization disorders which are usually genetic inborn errors in the skin cycle. In skin disease this cycle can be disrupted resulting in flakiness, excessive oil deposition, increased pigmentation, sores, itching, excessive dryness, etc. In these cases the skin disease is known as secondary keratinization disorders. Shampoo therapy can often help normalize the keratinization cycle.
Important points of shampoo therapy include:
- Contact time – follow manufacturers label directions and/or your veterinarians specific advice. Most shampoos allow for 5-15 minutes of contact time which facilitates the action of the shampoo.
- Frequency – this is usually up to the discretion of your veterinarian. Usually 2-3 applications weekly are a good starting point to get a response and then the frequency is tapered to every 1-3 weeks as needed
- Protocol — I generally like to completely soak the coat with warm water first. Some veterinarians advise briefly washing the dog with a hypoallergenic pet shampoo first to decrease the water repellency of the coat. Then apply the medicated shampoo. This is especially useful in breeds with heavy undercoats. Brushing the heavy-coated breeds prior to bathing helps also — we want the shampoo to contact the skin not the hair.
- Maintenance – it is important to maintain proper grooming between shampoo therapy sessions. This includes brushing to remove dead hair, scale and mats, and to promote oil deposition on the skin.
- Antiseborrheic Shampoos
These shampoos are directed at eliminating surface scale and restoring the normal skin cell replenishment cycle and function.
- Sulfur and salicylic acid – these shampoos tend to be antifungal, antibacterial, antiparasitic, antipruritic (anti-itch) and normalize skin function. Examples include: Sebolux® (Allerderm), SebaMoist® (EVSCO) and SeboRx® (DVM).
- Tar Shampoos — These shampoos are used primarily in cases of greasy, scaly skin disorders. They are a product of distillation of coal and certain types of woods — be careful as they can cause drying or irritation. Properties of these shampoos include eliminating surface scale, degreasing, decreasing skin inflammation, and decreasing itching. Examples include: EVSCO-Tar®, NuSal-T® (DVM), T-Lux® (Allerderm), AllersebT® (Allerderm) and LyTar® (DVM).
- Selenium sulfide – These shampoos are degreasing and remove epidermal scale on the skin surface. They can be drying and irritating to the skin. An example in this category is Selsun Blue® (Ross).
- Benzoyl peroxide – properties of these shampoos are antibacterial, follicular flushing, degreasing and scale removal. Examples are: Benzoyl-Plus® (EVSCO), Pyoben® (Allerderm) and SulfOxyDex® (DVM).
- Antibacterial Shampoos These shampoos have antibacterial activity and are very useful in the treatment of bacterial skin disease (pyoderma).
- Benzoyl Peroxide (see above) – one of the most active antibacterial agents with a residual effect for up to 48 hours.
- Chlorhexidine – chlorhexidine has broad spectrum activity against bacteria, fungi and yeasts. Has a rapid kill and up to 36 hours residual activity. Examples include: ChlorhexiDerm® (DVM), Hexadene® (Allerderm), SebaHex® (EVSCO) and Universal Medicated® (Vet Solutions).
- Ethyl Lactate – this agent has very good antibacterial activity. Etiderm® (Allerderm) is a 10% concentration in a nondrying, degreasing Shampoo.
- Antifungal Shampoos
- Imidazoles – inhibit the growth of fungal and yeast organisms. These Shampoos are valuable in the treatment of ringworm and Malassezia dermatitis. Examples are: Dermazole® (Allerderm), Miconazole Shampoo® (EVSCO), Nizoral® (Janssen), Malaseb® (DVM) and Ketochlor® (DVM).
- Antipruritic (Anti-itch)Shampoos
- Oatmeal-based shampoos – these act by adsorbing surface allergens and itching mediators to the fine colloidal oatmeal particles. These are then rinsed away. Examples include: Dermal-Soothe® (EVSCO), Episoothe® (Allerderm) and Relief® (DVM). A powdered oatmeal formulation to be added to a cool bath is also available as EPISOOTHE® and AVEENO®.
- Cleansing and Moisturizing Shampoos
These shampoos are medicated and hypoallergenic products that clean without soap. They function to rehydrate and cleanse the skin. Examples are: Allergroom® (Allerderm), HydraPearls® (EVSCO) and HyLyt EFA® (DVM).
- Antiseborrheic Shampoos
My indications for shampoo therapy in Shar-Pei center on demodectic mange, allergic skin disease, horsecoats with oily skin and odor, bacterial skin infections and Malassezia dermatitis. I use Pyoben® shampoo quite a bit for secondary skin infections (“elephant skin”) which often accompany allergic skin disease due to the itching. I also use Episoothe® in those itching allergic dogs where there is not a secondary pyoderma. Dermazole® shampoo is useful in allergic dogs with secondary Malassezia (yeast) dermatitis. I especially like to use a tar and sulfur shampoo such as AllersebT® in horsecoats with the oily, rancid-smelling coats. ALWAYS CONSULT WITH YOUR VETERINARIAN BEFORE STARTING SHAMPOO THERAPY OR FOLLOW THEIR TREATMENT PLAN FOR YOUR DOG. Your veterinarian may have different shampoos in their arsenal which will be just as effective as those I like to use. If the shampoo you are using causes the skin problem to become worse or causes any skin irritation at all, stop the shampoo and discuss the problem with your veterinarian.
Lastly, I’m often asked what shampoo to use routinely in Shar-Pei. Any shampoo formulated for dogs can be used and any human baby shampoos are adequate for routine use. The same recommendations apply as discussed above – if skin irritation, redness, etc. develop then stop using the shampoo and try another. I’m also asked about how often to bathe your dog. I usually bathe my dogs when they get dirty or smelly. This means I bathe them more often in the spring, summer and early fall and less often in the winter. I would not advise routine bathing more often than every 2-4 weeks as skin dryness will often develop. I often will bathe only affected areas when there is a skin problem where shampoo therapy is indicated instead of giving a complete bath.