A Plaister for the Temples.
Take Caranna 1 dram; Spread it upon a fitting piece of Leather, and put in the middle of it Opium 2 grains; Oil of Amber 4 drops.
It's an Anodyne; applied to the Temples, it hath power against Restlessness and Headach: Behind the Ears, it takes away pain of the Teeth.
Two Twigs of the external Carotid Artery running under the Ear, and entering into the inferior Maxilla, are disseminated thro all its length, into the Roots of every Tooth, to carry Blood for their Nourishment. In these Vessels, acrid Humours (together with the Blood) pass to the Teeth, and gnaw and vellicate the exquisitely sensible Membrane, that coats their interior Medulla, and are the cause of the intolerable shooting twinging Pain. And from this Origine of the Arteries that run to the Teeth it is, that Remedies behind the Ears are found more successful in the Tooth-ach, than at the Temples, faith the same Highmore.
Thomas Fuller
Pharmacopeia Extemporanea 1710