I find I am often asked for herbal cures for problems which are easily treated by over-the-counter remedies. As much as I do appreciate the desire to go back to nature and live as the Goddess wills, I've been around long enough to respect the potential dangers of letting every day illnesses and injuries get out of hand. Open wounds go septic, colds become walking pneumonia. Herbal medicine is a wonderful thing, but it can be dangerous for the novice to self-medicate.
If you really need to rationalize the use of over-the-counter medicines, technically it all comes from the Earth. Many of the medications we take for granted today originated as herbal remedies. Pharmaceutical companies comb rainforests and primitive cultures for the next superdrug. The Mother provides. Bayer, Pfizer and Johnson and Johnson simply make it more easily accessible.
When using aspirin magically, we turn to the magical correspondences of the willow tree. The willow is used in lunar magic, particularly New Moon magic, as well as in love, fertility, protection and obviously, healing. It is associated with the element of water. The goddesses Hecate, Artemis, Astarte, Ceridwen and Rhiannon consider the willow sacred. In folklore, a witch's broom is bound in willow.
So as you take your aspirin, for whatever ails you, remember to give thanks to the Mother, or to the goddess of your choice for the willow tree which created it, and of course, use only as directed.