The dermatologist is usually confused by the multiplicity of medicaments which are found in even the simplest pharmacopoeia; yet successful treatment of all the common diseases can be achieved by the use of a very small number of topical applications. Dermatologists, like cooks, have their favourite recipes and listed below are a minimum number of our favourite prescriptions and techniques with their main indications and a very brief description of the principles upon which the vehicles work. The methods by which they should be applied have been described elsewhere in the book but explanation to the patient of how medicaments should be used is an essential part of the treatment all too often omitted. Topical applications consist of vehicles, which are used to convey the active drug to the skin. Since corticosteroids are used so widely in the treatment of common conditions such as dermatitis and eczema they will be mentioned first.
Topical steroids can be prescribed in lotions, creams or ointments, and recently new methods of first dissolving the steroid in propylene glycol have made the steroid more readily released with the result that the same anti-inflammatory effect can be obtained with lower concentration of steroid. Thus the physical state in which the medicament is held in the vehicle is of importance and there are numerous advances occurring all the time in the pharmacy of steroid vehicles.
The anti-inflammatory effect of steroids can be divided into those which approximate to 1 per cent hydrocortisone and which will control simple dermatitis and the much more powerful fluorinated steroids such as triamcinolone, fluocinolone and betamethasone valerate, and even more powerful fluocinonide and clobetasol propionate which may be needed for chronic eczema and psoriasis. The fluorinated steroids have the disadvantage of producing atrophy of the epidermis and dermis.
Some non-fluorinated steroid compounds appear to have a potency greater than hydrocortisone and yet cause little skin atrophy. Hydrocortisone butyrate (Locoid) is one of these.
In hospital practice it has been customary to dilute the fluorinated steroid creams to provide a larger quantity of cream to spread on to extensive skin lesions, and provided a suitable diluent is used and sterility is observed this is permissible. If the wrong diluent is used then the steroid activity may fall, and of course bacterial contamination may occur in the mixing process. Suitable diluents are cetamacrogol A (BPC) for betamethasone valerate (Betnovate) and cetamacrogol B (BPC) for fluocinolone acetonide (Synalar). A 1 in 10 dilution of these approximates to the power of 1 per cent hydrocortisone. Outside hospital it is preferable to use the standard proprietary dilutions which have been made up under sterile conditions. Synandone, a dilution of fluocinolone and ultradil, dilute fiuocortolone are widely prescribed. Fluocinonide (Metosyn) being dissolved in propylene glycol must be diluted in its own diluent. Steroid ointments which are less prone to bacterial contamination can be diluted in soft paraffin.
Polythene occlusive dressings
The penetration of corticosteroids in the skin can be increased and the anti-inflammatory effect enhanced by covering the area with an airtight plastic film dressing. This should not be left on for more than 8 hours at a time and can conveniently be done at night. Such treatment should be reserved for resistant thickened lesions and with an awareness that prolonged use of the method may produce skin atrophy and systemic absorption of the corticosteroid.
Lotions are used to cool inflamed skin and act by evaporation, thus should be reapplied frequently on gauze or linen, never lint.
For acute exudative conditions and general anti-inflammatory use:
Wet dressing of shake lotions:
Lotion terra silica.
White Fuller’s earth 4.4
Zinc oxide 4.5
Water to 100
or calamine lotion B.P.
In endogenous eczema 1/4 per cent of crude coal tar may be added to the lotion as an anti-pruritic but should be mixed with the glycerin alone in the course of preparation. It should not be used in contact dermatitis as the tar may be irritating.
If pyogenic infection is present wet dressings of 1/4 strength sodium hypochlorite dilute solution BPC (Milton) is clean and effective.
These are a suspension of powder in a greasy base, usually soft paraffin.
For subacute and chronic dermatitis:
Lassar’s paste (Zinc and Salicylic acid paste BP)
Salicylic acid 2
Zinc oxide 25
Starch powder 25
Soft paraffin 100
Crude coal tar can be added as an anti-pruritic, 1 per cent or 6 per cent being the most useful strengths.
In the most severe cases:
Coal tar and Zinc Ointment BPC
Strong coal tar solution 10
Zinc oxide 30
Yellow soft paraffin 60
Creams are of two types, water in oil emulsions which are greasy and less easily soluble in water. Oily cream BP is an example of this type useful for dry skins. Oil in water emulsions are easily removable by water and particularly applicable for hairy areas. Aqueous cream BP is an example which can be used as an emollient and a vehicle for medicaments. Where there is a risk of lanolin sensitivity, cetamacrogol cream should be substituted.
Non-emulsifying ointments such as paraffin ointment tend to macerate the skin but are useful in certain situations.
Crusts can be easily removed by the application of the following ointment thickly spread on lint strips and left in position for 24 hours.
Lead diachylon plaster, Soft paraffin } equal parts
Hyperkeratotic skin may also be softened by the use of 10-20 per cent salicylic acid in soft paraffin.
Used in the treatment of severe venous ulcers of the legs. It is a combination of massage and firm elastic support.
1 Moisten the bare hands with olive oil, raise the patient’s leg and rest it on a small table.
2. Massage the sole firmly from toes to heel.
3. Massage the hollows behind the malleoli from the foot upwards.
4. Massage the lower leg and the area round the ulcer to mobilise the ulcer from underlying scar tissue.
5. Give passive and active movements to the ankle joint to improve its mobility.
6. Apply a dressing to the ulcer and bandage this in place with a cotton bandage.
7. Apply a pad of gamgee to completely encircle the lower half of the leg. Bandage this in place with a 6-inch cotton bandage from toes to knee.
8. Apply an elastic web bandage (blue line) firmly from the base of the toes, keeping it evenly bandaged by following blue line and leaving no gaps round the heel. The bandage must be applied from the toes to just below the knee.
The patient removes the elastic bandage when going to bed but leaves the rest of the dressing in place until the process is repeated the following day.
Zinc sulphide lotion BNF
Sulphurated potash 5
Zinc sulphate 5
Camphor water to 100
To cause peeling in severe cases
Zinc paste to 100
A mild cosmetically acceptable preparation:
Salicylic acid and Sulphur cream BPC.
Salicylic acid 2
Sublimed sulphur 2
Aqueous cream 96
For dry scaly scalp due to seborrhoeic eczema or mild psoriasis and those who are coal-tar sensitive:
Cade oil 24
Yellow beeswax 12-5
Soft paraffin 62-5
Psoriasis for routine use:
Coal tar and Salicylic acid BPC.
Strong coal-tar solution 10
Salicylic acid 2
Yellow soft paraffin 10
Emulsifying wax 18
Hard paraffin 10
Coconut oil 50
For more resistant patches:
Dithranol 1/4 to 2 per cent in a mixture of hard and soft paraffins.
For very severe scalp psoriasis:
Ung. Pyrogall. Co.
Pyrogallic acid 2.5
Salicylic acid 4
Carbolic acid 2-5
Soft paraffin alb. to 100
Dithranol pomade (Stieffel)
For fungus infections of groins and toe clefts:
Magenta paint BPC (Castellani’s paint)
For chronic scaly fungus infections:
Benzoic acid compound BPC (Whitfield’s ointment)
Benzoic acid 6
Salicylic acid 3
Emulsifying ointment 91
Liquor picis carbonis 120 ml added to 90 litres of water. Used to sensitize the skin to ultra-violet light in the treatment of psoriasis.
Added in the quantity recommended by the manufacturer. Useful to grease the skin in mild ichthyosis and to prevent degreasing of the skin in eczema and senile pruritis.
Emulsifying ointment bath
Place 20—40 g of emulsifying ointment in a basin and mix it with hot water. Add to the bath water (20 g for an infant bath). Used to prevent degreasing of the skin in infantile and atopic eczema.
Examination of hair, nails and skin for fungus infection
Pathogenic fungi remain viable in hairs, nail clippings and skin scrapings for long periods which enables specimens to be sent to specialised laboratories even many miles away. Scrapings should be obtained from the spreading edge of lesions either with a scalpel or Volkman’s spoon. The material can be conveniently preserved dry—preferably in black paper.
This procedure is carried out under local anaesthesia. A characteristic early lesion should be selected and, if a small blister or nodule, removed entirely. When only part of a large lesion is removed an ellipse of skin which includes a piece of normal skin and the transition to diseased tissue must be taken. A strip of skin cut out with a scalpel is to be preferred to a punch biopsy. It is important to include all layers of the skin down to subcutaneous fat since it is impossible to decide whether a tumour is invading the dermis if only epidermis can be seen. The biopsy specimen should be put in fixative (10 per cent formalin) immediately.