dōTERRA On Guard, a proprietary essential oil blend, provides a natural and effective alternative for immune support when used internally.* As one of dōTERRA’s best-selling blends, dōTERRA On Guard protects against environmental and seasonal threats with essential oils known for their positive effects on the immune system when ingested. dōTERRA On Guard can be taken internally on a daily basis to maintain healthy immune function.* It can also be used on surfaces throughout the home as a non-toxic cleaner. When diffused, dōTERRA On Guard helps purify the air, and can be very energizing and uplifting