6 Topical treatment is probably the most important therapeutic intervention in the management of any dermatosis. However, modification to the usual regimens are sometimes required when they are used on the vulval skin. It is important that anyone treating patients with vulval disease is fully aware of how to use these topical treatments appropriately, the potential side effects and how to avoid them. Patient education is vital for the correct use of any topical therapy in order to achieve compliance, obtain the best results and avoid adverse effects. As there is direct contact between the drug and the diseased tissue, the risk of systemic side effects is minimal. A topical treatment (Table 6.1) generally consists of an active ingredient mixed with a carrier or vehicle. This vehicle allows for delivery of the drug into the epithelium and many of the more recently developed treatments contain a vehicle that is tailored to the active drug to achieve maximum efficacy. Therefore, it is important not to modify the specific drug‐vehicle system (such as mixing directly with an emollient) as this may significantly alter the delivery and absorption of the active drug. The vehicle must allow maximum stability of the drug and should not have any irritant or allergenic properties. It must also be easy for the patient to apply and must be cosmetically acceptable. Table 6.1 Classification of topical treatment. Drugs penetrate the skin barrier depending on their solubility in lipid and water. However, when the epidermal barrier is abnormal in a diseased state, the penetration can increase significantly. There is also increased absorption in flexural sites due to the natural occlusion, which is very important in the treatment of vulval disease. The addition of a chemical such as propylene glycol can greatly increase the penetration as it causes vasoconstriction. This is rarely needed for treatment of the vulva. Lotions are liquid preparations. They include ‘shake lotions’, where an insoluble compound is suspended in a liquid; for example, calamine lotion. They are easy to apply but are not particularly useful in the treatment of vulval disease. These are not greasy, are washed off easily and are helpful in hair‐bearing areas such as the mons pubis and labia majora. These are by far the preferred formulation for use on the genital skin. They are anhydrous substances and are thicker and greasy for the patient to apply. However, they have an occlusive and therefore protective effect, which is very useful on the vulva where there are several irritant factors that can aggravate the skin. These contain both oil and water. Oily cream preparations have a greater moisturizing effect. All creams contain preservatives against bacterial and fungal infection and it is these that often lead to a secondary irritant or allergic contact dermatitis. The differences between gels, ointments and creams is shown in Figure 6.1. Pastes are rarely used for active treatment on the vulva but can be useful when a barrier preparation is required. Emollients are an important part of the management of any vulval disease. They provide lubrication and moisture when the skin barrier loses its normal structure and function. Patients with vulval symptoms frequently start washing more often in the belief that this will help. The increased use of soap, antiseptics and water can lead to a loss of the natural lipids resulting in a deterioration of the problem. Emollients act to provide moisture and protection at this point. An effective way to deliver an emollient is to use an ointment such as emulsifying ointment as a soap substitute (Figure 6.2). This can be made into a creamy liquid by rubbing the hands together in warm water. Then this can be used to wash the vulva (Figure 6.3). If patients are also using cream emollients at other times, then the potential for sensitization from excipient ingredients in the preparation should be remembered. Topical steroids have revolutionized the treatment of inflammatory skin disease. However, there has been much publicity about the potential side effects of these treatments and patients are often very worried about using them. The package insert for patients generally states that they should not be used on the genital skin. A thorough explanation of the correct and safe usage of topical steroids should therefore be given to the patient when they are prescribed. Topical steroids have several different mechanisms of action but it is not known exactly how these take effect. They are anti‐inflammatory, vasoconstrictive and immunosuppressive and reduce mitotic activity.
Topical Treatment in Vulval Disease
Introduction
General principles
Liquid
Aqueous
Lotions
Gels
Alcoholic
Paints
Emulsions
Semisolid
With water
Creams
Emulsions
Without water
Ointments
Pastes
Lotions
Gels
Ointments
Creams
Pastes
Topical treatments used for vulval disease
Emollients
Topical steroids