The external & the internal: the same but different

The elders often speak of the need to consider the unity of opposites; the outside and inside, the exterior and the interior or, to use the terminology of graphic design, the stroke and the fill. One cannot have one without the other just as light cannot exist without the dark. They exist together in one mutually-arising entity.
That being said there is a massive difference in the pain levels experienced when one unwisely applies Voltarol to both internal and external haemorrhoids. So although anti-inflammatory gel should be applied to neither (one entity mutually-arising) the pain from the interior almost induces fainting while the exterior only mild pain and irritation (innate duality).
So to recap: opposites are the same but different, anti-inflammatories are complex and last but not least, always read the label.