Is it post-inflammatory hyperpigmentation or post-inflammatory erythema? At first glance, these spots can appear very similar, especially on darker skin tones. However, hyperpigmentation is associated with skin darkening, and erythema is associated with skin redness. Here’s a clever hack: Press lightly on the area with your finger for a moment. Release your finger, and if the blemish disappears for a moment, it’s erythema. If it remains, it’s hyperpigmentation.