Casuistic and methods
3.1.1. Study design
The study was approved by the Committee on Ethics in
Research with Human Beings of the Faculty of Pharmaceutical
Sciences of Ribeirao Preto, University of Sao Paulo (Protocol
CEP-FCFRP no. 45). Twenty volunteers, aged 25–55 years, with skin
types II–IV [23] were selected and signed the Term of Informed
Consent after being oriented as to the objectives and research
methods.
Formulations containing or not 1% IPAA were applied to the face
and forearm of each volunteer, daily, for 15 days. Before starting
the measurements, the subjects stayed during 30 min in a temperature
and humidity controlled environment (20–22 C and 45–55%,
respectively) for acclimatization [16,24]. Measurements were
made before application (basal values), 3 h after (immediate effect)
and 15 days later (long term effect).