The terpinene-4-ol contained in tea tree oil has broad-spectrum antimicrobial activity. Lavender oil contains linalool which also has antibacterial properties. So, they can be anti-acne. Both oils are formulated as emulgel hand sanitizers because this form has a better-controlled drug release effect and stability. The emulgel contained tea tree oil at 5% combined with lavender oil at 0.5%, 1%, and 2%. The evaluation consisted of physical and chemical characteristics, irritation, and antibacterial activity on skin bacteria. The results showed that each organoleptic formula had white color and a distinctive aroma of both essential oils. The texture was soft, homogeneous, and oil-in-water emulsion type; the viscosity and pH were within the specification range. All the formulas met the dispersion requirements. For the irritation test result using HET CAM methods, the preparation caused mild irritation, and the value of the irritating score increased when lavender oil levels increased. In the antibacterial test for Cutibacterium acnes, the addition of lavender oil intensified the antibacterial activity of tea tree oil. On the other hand, an antibacterial test for Staphylococcus aureus and Staphylococcus epidermis of lavender oil added to tea tree oil does not influence the antibacterial activity of tea tree oil in emulgel preparation.
Keywords: emulgel of combination tea tree oil and lavender oil, characteristic, irritation effect, antibacterial propert
