[Corticotherapy and mucocutaneous pathology]

The tremendous advances in treatment brought about by corticotherapy applied to cutaneo-mucosal pathology should not be allowed to obscure the fact that its action is merely palliative, that it should only be proceeded with after careful diagnosis and that it may trigger undesirable side-effects. General corticotherapy is definitely indicated in certain serious dermatoses (e.g. pemphigus vulgaris) in large doses at the beginning of the course of treatment which often has to be kept up indefinitely; it is in these patients that the most serious accidents occur. It is also indicated in other dermatoses (e.g. lichen planus) in smaller doses and in separate courses, generally triggering incidents and accidents of a less serious nature which to a certain extent seem to be attenuated by taking the drug on alternate days. It is counter-indicated in one particular condition: psoriasis. Corticotherapy by intra- and sub-lesional local injection is most useful in the treatment of certain localised skin lesions (e.g. cheloids) and of the oral mucosa (e.g. erosive lichen planus). Either a few drops are injected or a larger quantity in a suspension of microcrystals. Complications have sometimes been observed in the skin (leukoderma, dermoepidermatrophia and, particularly, amaurosis), but never so far after sub-mucosal injections. Local corticotherapy by external application, very widely used in the form of ointments, creams and lotions for numerous cutaneous conditions may cause various more or less serious local side-effects, the systemic effects with depression of the hypophyso-adrenal axis, only seem to occur to any extent with occlusive dressings. It can also be used in the treatment of some conditions of the oral mucosa (e.g. some forms of lichen planus, benign mucous membrane pemphigoid) by means of either a corticosteroid incorporated into a special excipient which adheres to the mucous membrane or in tablets of 17-betamethasone valerate which gradually break up in the saliva. With the usual posology of 10 tablets of 0.1 mg per day, even over several months, there are no systemic effects, 17-betamethasone valerate (unlike phosphate) having an action which is primarily topic and being practically unabsorbed as has been shown by assessment of plasmatic cortisol.