Tea Tree Oil. Most essential oils have some antiseptic properties, but tea tree oil is especially powerful. Tea tree oil's infection killing ability makes it the best choice for attacking the source of the infection. To maximize tea tree oil's antiseptic action, use it in a steam inhalation.avis claims this treatment both eases the pain and helps stop the infection's spread farther into the ear. In The Complete Guide to Essential Oils & Aromatherapy, Valeria Worwood recommends a different method--add a drop of lavender and a drop of chamomile essential oil to 1 tsp. warm olive oil and mix well.