Human Repeated Insult Patch (HRIPT), Shelansky & Shelansky / Marzulli & Maibach:
The Human Repeated Insult Patch Test is aimed to assess the incidence of skin sensitization which may be induced by the test product when repeatedly applied on the skin. The test is carried out on healthy subjects under occlusive/semi-occlusive/open conditions, depending on the chemical-physical characteristics and the intended use of the product. Each subject is exposed to product for 48 hours repeatedly applied over a 3-week period in the same skin site and skin reactions are assessed after each patch removal. After a 2-week break (resting phase), a naïve site is selected for a “challenge” 48 hours exposure. Skin reactions (redness and swelling) are assessed by a highly trained assessor (dermatologist) up to 72 hours upon patch removal. The HRIPT may be performed according to Shelansky & Shelansky or Marzulli & Maibach methods.
