SIDE EFFECTS AND INTERACTIONS OF WINTERGREEN OIL
High doses can be toxic and even painful, so avoid overconsuming wintergreen oil or applying it directly to skin. Use very small quantities of wintergreen oil, especially if you are new to trying it. Also be careful to keep it away from your eyes, the mucus membranes inside of your nose, pets and babies. Because methyl salicylate can be harmful when used on open wounds, internally, on babies or children, and on anyone with allergies, use caution and start slowly.
If you have sensitive skin, there’s a chance you can react badly to mint oils and might experience redness, burning and swelling, so do a small patch test first to make sure you don’t experience any side effects. Try testing one to two drops on an area of your skin that isn’t sensitive, such as your feet or calves. Make sure you can tolerate wintergreen oil well before using it internally or on larger parts of your body.
Avoid using wintergreen oil internally unless you’re working with a professional. Ingesting it can possibly cause side effects for some that include heartburn, flushing, mouth sores, headaches, rashes and acid reflux. Some prescription medications and over-the-counter medications can also adversely interact with wintergreen when it’s consumed, so speak with your doctor if you take any digestive or asthma medications, blood thinners, pain medication, or anti-coagulants.