Pegagan has activity as an antibacterial, so that required to be formulated into comfortable and practical used dosage form such as gel. Formulation of ethanolic exctract of Centella asiatica need gelling agent in order to obtain a gel which fulfill the physical properties requirement of gel and not cause irritation effect. The aim of the research to know the influence of the type of gelling agent toward the physical properties and irritation potential of gel of ethanolic extract of Centella asiatica, L. The extract was gotten by maceration method by using 70% ethanol. The extract was formulated become gel. The physical properties of gel was evaluated by organoleptic test, pH test, adhesivity test, spreadebility test, and skin irritation test. Data was analyzed with statical analysis using ANOVA test ab kruskall wallis test and then continued with Mann Withney test with 95% of confident level. Result of the research indicate that variation of gelling agent have an effect on spreadability and adhesivity of gel of ethanolic extract of Centella asiatica, L. The gel that has biggest spreadibility power is gel with HPMC formulation with the value 52.282 ± 2.515 mm2 and the smallest spreadibility power is gel with carbopol combinated with extract formulation with value 27.818 ± 1.023 mm2. While for the smallest adhesivity value on gel with HPMC formulation is 1.632 ± 0.289 second, and then the biggest adhesivity value on gel with carbopol is added extract is 3.614 ± 0.128 second. Variation of gelling agent did not influence of all of the gel formulas did not have irritation effect to marmut skin and pH value. The right gelling agent for ethanolic extract of Centella asiatica, L is carbopol because carbopol has a good spreadibility, good adhesivity, and minimal of irritation effect.
Key words: Centella asiatica L, gelling agent, physical properties of gel, irritable potential
