Ointment is evenly spread on the skin, in contrast to creams and solutions.
BACKGROUND
The efficacy of topical therapy depends on the patient spreading the topical drug in an even layer to give a standard dose. Ointments are believed to be more effective than creams and solutions.


OBJECTIVE
To compare the application and spreading of four different pharmaceutical vehicles.


METHODS
Twenty-nine healthy volunteers applied a fixed amount (0.1 g) of solution (S), ointment (O), cream (C) and low-viscosity cream (LVC) to the abdominal skin. Area of spread, skin surface lipids (dependent on formulation) and changes in skin surface temperature (cooling due to evaporation of formulation water/alcohol) were measured.


RESULTS
Area of spread: O = C = LVC = S. Skin surface lipids: O > C > LVC > S. Difference in skin surface lipids between centre and periphery: O < C = LVC = S. Cooling: O < C = LVC < S.


CONCLUSIONS
The four formulations were spread to similar areas. The ointment was spread evenly in the treated area while the other formulations were unevenly spread, with a lower dose in the periphery. Creams and solutions have disadvantages as vehicles, as rapid evaporation of formulation water/alcohol, measured as cooling, influences spread, resulting in an uneven topical dose within the treated area. In contrast, ointment is evenly spread and is thus a more appropriate formulation. Patients should be instructed to apply creams and solutions to multiple sites and to spread them quickly.
Ivens
U I
UI
Dermatological Research Department, Leo Pharmaceutical Products, DK-2750 Ballerup, Denmark.
Steinkjer
B
B
Serup
J
J
Tetens
V
V
D000287:Administration, Topical; D000328:Adult; D000704:Analysis of Variance; D001831:Body Temperature / Q000187:drug effects; D018592:Cross-Over Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009824:Ointments / Q000008:administration & dosage*; D010349:Patient Compliance; D019999:Pharmaceutical Solutions / Q000008:administration & dosage*; D011446:Prospective Studies
D009824:Ointments; D019999:Pharmaceutical Solutions