My oldest has been having a bit of the allergy stuffy nose sniffles (the only downside to our wonderful new backyard with mature trees) but I was determined not to medicate her un-neededly. Here's the blend that worked great and she called it her "candy cane" medicine.
2 drops peppermint
2 drops lavender
2 Tbsp water
Just be sure to use DoTerra oils, not all essential oils are okay to take internally.