A new thing I am doing to DC is use peppermint oil with my Quick Cap.
I would like to add shea butter or a base to the oil but I am not sure what to use that is 100% natural.

Okay, if you are talking about peppermint essential oil, you should add it to a carrier oil in less than 1%.

Good oils to use as the carrier. These are great because you can buy them locally.
Olive oil- doesn't have to be virgin, pure is fine.
Smart Balance cooking oil - a mix of canola, soy, olive and vitamin e oils. All oils that are good for skin and hair (inside and out)
Coconut oil - supermarket brand is fine. Just read the ingredients to make sure its only coconut.

Add one or two drops of peppermint oil to 2 ounces of carrier oil. Peppermint oil in too large an amount will irritate your skin.

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