CLINICAL EVALUATION OF ANTIDANDRUFF FORMULATIONS By HERBERT J. SPOOR, PH.D., M.D.* Presented September 19, 1962, Seminar, New York City Da, NDP. trFF is the common name given to the scalp conditions pro- duced when the continuous but normally imperceptible sloughing of the outer epidermal layers of the skin becomes grossly visible. The scale con- sists of desquamated epidermal cells, accumulated secretions and acquired soil. Whe.'-•there o no obvious overactivity of the oil producing sebaceous glands, the condition is called Pityriasis capitis or Seborrhea sicca with excess oil production it becomes Seborrhea oleosa and if it is accompanied by an erythematous or eczematized involvement of the outer skin itself it becomes seborrheic dermatitis. Figure 1 illustrates this sequence. Antidandruff preparations are intended for treatment of Seborrhea sicca (a):and Seborrhea oleosa (b). However, if the condition has progressed either through local eczematization (c) or has spread to other body areas of predilection (d), more than topical therapy is often required to achieve control. The mechanics of dandruff formation are best illustrated in a cross sectional view of the skin. Normally, the gradual sloughing of the dead and hardened outer epidermis exactly balances the constant production of new cells from the germinal layer below. Figure 2, which shows com- parative photomicrographs of the skins of several animals and man, illustrates that this property of continuous growth is common to all animal skins, but it also shows human skin differs from that of the lower animals. In the human, there are more layers of viable and partially viable cells between the living, germinative basal layer of the epidermis and the tough, outer, fully keratinized layer, and therefore, any disturbance in the balance established between the constant production of new cells and the rate of sloughing of the old may produce visible masses of epidermal cellular debris that we call "dandruff." This is not identical to animal "dander" which consists primarily of keratin flakes. Most animal skins do not have the relatively thick, tough epithelium characteristic of man but depend for their strength upon a more fibrous, more heavily haired subepidermal * Cornell University, College of Medicine, Ithaca, N.Y. 135

136 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS .& /... Figure 1.•Seborrheic diathesis. (A) Seborrhea sicca. (B) Seborrhea oleosa. (C) Seborrheic eczema--local. (D) Seborrheic eczema•other areas.