SOME DIFFICULTIES OF TOPICAL TREATMENT IN DERMATOLOGY 43 greasiness of their skin which may link with Skog's work that anionic detergents do have a hyperplastic effect upon sebaceous glands. I believe that hexachlorophene and the Parabens are already used as antibacterial agents in shaving creams. I should have thought that people who have the type of skin which easily gets infected, or that which does not stand up to over-washing, might well be helped by putting an anionic detergent into shaving cream. I am unable to answer your last question. DR. H. W. HIBBOTT: I would like to make two comments. As I was listening to you I felt that we had a refreshing change in the dermatologist's outlook towards cosmetics. Apart from a slight indictment of bergamot you have not come down heavily on cosmetics as a great cause of trouble for the medical profession, very contrary to some lectures we have listened to in this Society from dermatologists. I think this represents a change to which this Society has been looking forward for some years. Looking at some of your rather wonderful slides, even when we saw lips in very bad condition you did not blame it on lipsticks. In this case, too, I feel that lipsticks, apart from being quite glamorous, are in fact very good lip salves and women are a very lucky half of the population in being able to wear them. I was very impressed by your outlook towards the cosmetic industry, and I feel that we ourselves are showing that we are really thinking hard about possible adverse effects on the skin, and that the results we are getting are showing up to the medical profession. MR. 13. CHtMBERS: Can you suggest the main cause of itching which accompany acute cases of dandruff ? THE LECTURER: Dandruff comprises dead cells (dander) which are being exfoliated .and are being shed as a result of p•roteolytic enzymes. As a result you are bound to get some itching sensation as a normal state of affairs. Itching in the perianal region is very commonly due to bacterial breakdown of protein. Bacteria can grow very easilyin a greasy, sebaceous area, and once you have a combination of desquamated cells with sebum you have a medium in which organisms will grow, and itching results. I would have thought that head itching is very often related to staphylococcal or ,other infections. You can, however, get emotional itching of the head, which may be due to some alteration in tension in the erector pili muscle, the hair standing .on end through nervous sympathetic stimulus when you get anxious. People also go white due to nervous vagotonic influences. Thus a state of tension affecting the hair muscle will produce itching. It is very common for people to scratch their head -in order to get rid of their tension. MRs. H. BUTLER According to you, as I understand it, some irritation is caused by blocking of the sweat gland. Is it not also caused by changes of temperature ? know a man who only gets severe itching in frosty weather, leading to eczema when he gets in front of a hot fire. That is not necessarily blocking of the sweat glands, it ? THE LECTURER: This is another problem the vascular supply of the skin differs in many places and once the skin is damaged the vessels become unstable and will leak. The response to histamine is also different. If you burn your hand, the result of that burn may lead to an unstable bit of skin which will flush up easily for as

44 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS long as three years afterwards. With a winter eczema the vessels underneath it are equally unstable, and will flush up and leak more easily. In front of a fire the vascular changes may themselves increase the temperature and congestion, which will press on nerve fibres and cause itching. You are quite right- itching is much more easily elicited at high than at low temperatures. MRs. H. BUTI, ER: Why does this only happen during frosty weather ? THE LECTURER: The skin gets dehydrated and therefore little spicules of keratin are standing up, thus the skin is non-intact and more easily injured by the friction of the clothes. MR. A. G. McGEE: Would you care to expand on your statement in page 35 that "phenol and other coal tar distillates are much less likely to irritate though a few are intolerant" ? T-HE LECTURER: Phenol and coal tar distillates can be both irritants and sen- sitizers, but are mainly irritants. The majority of individuals are unable to tolerate tar on skin. The problem is that the more you remove the phenol, which has an anaesthetic effect upon the nerve fibre, the less anti-itching effect is obtained. People who are intolerant of the tar acids are not going to be helped by removing the phenol component, because it is going to be less effective for them. Summarizing, crude coal tar is by far the most effective antipuritic agent- but the more it i• purified the less anaesthetic effect does it have upon the nerve fibres. MR. C. PARRY: What is your opinion about the suitability, and the possible mode of action of the purported hormone creams ? THE LECTURER: There is no doubt that hormones are very easily absorbed through the skin, and as they are absorbed they can produce both local and systemic effects if a patient is taking hormones for any other reason, you may get a summational effect. I believe I am right in saying that at the control trial of release bleeding at the menopause with hormone cream, and an emolient alone, the results did not seem to be very significant. It was thought that the main effect of the hor- mone cream related to the hydration effect of the keratin of the collagen. I fail to see how you are going to alter the collagen degeneration a great deal in the older person, though I think you can do something in the younger person.