Dark circles under the eyes are medically called periorbital hyperpigmentation, sometimes abbreviated as POH. You might also hear dermatologists refer to them as infraorbital dark circles. Despite the name suggesting a pigment problem, not all dark circles are caused by actual skin darkening. They fall into several distinct categories, each with a different underlying cause, and knowing which type you have determines what actually works to reduce them.
The Four Types of Periorbital Hyperpigmentation
Dermatologists generally classify dark circles into four categories: pigmented, vascular, structural, and mixed. Most people have a combination, which is why a single product rarely solves the problem entirely.
Pigmented dark circles result from excess melanin deposited in the skin beneath and around the eyes. Sun exposure, hormonal changes, and genetic predisposition all contribute. This type is more common in people with darker skin tones, and the discoloration tends to look brown or dark brown.
Vascular dark circles come from the blood vessels beneath your lower eyelid skin showing through. The skin around the eyes is some of the thinnest on the body, and it provides almost no camouflage over the dense network of blood vessels and the orbicularis muscle underneath. When tiny capillaries leak, breakdown products of hemoglobin (the oxygen-carrying protein in red blood cells) deposit in the surrounding tissue, adding a visible purple or blue-brown tint. This type often looks purplish or bluish.
Structural dark circles are caused by shadows, not color. A depression called the tear trough, a groove roughly 2 to 3 centimeters long running below the lower eyelid, can cast a dark shadow over the inner corner of the eye. As you age, fat pads beneath the eyes shift and lose volume while the surrounding bone and soft tissue remodel, deepening that hollow and making the shadow more pronounced. Some people are born with a naturally deep tear trough, which is why even teenagers can have prominent dark circles.
Mixed dark circles involve two or more of these mechanisms at once, and this is the most common presentation.
Who Gets Them and Why
Periorbital hyperpigmentation affects all age groups, all races, and both sexes. That said, people with higher skin phototypes (darker complexions) are the most affected population, because melanin-related pigmentation plays a larger role. In one Indian study, prevalence was about 31%, with the majority of those affected being women. The average age of presentation hovers around the mid-30s, though it can appear much earlier.
Family history is one of the strongest predictors. Research has found a significant association between a positive family history and the presence of dark circles, which makes sense given that skin thickness, bone structure, and melanin distribution are all inherited traits. If your parents had prominent under-eye circles, you’re more likely to develop them too.
Sleep deprivation, allergies, dehydration, and excessive screen time are frequently blamed, and they do make existing circles more visible. Poor sleep leads to paler skin overall, which increases the contrast between your face and the naturally darker under-eye area. It can also cause mild fluid retention around the eyes, stretching the skin thinner and making blood vessels more conspicuous. However, the exact mechanism linking sleep loss to darker under-eye appearance hasn’t been fully mapped out.
A Simple Test to Identify Your Type
There’s a quick way to get a rough idea of what’s behind your dark circles. Gently stretch the skin of your lower eyelid downward with a finger and look in a mirror.
- If the darkness stays the same or barely changes: You likely have pigmented dark circles caused by melanin deposits in the skin itself.
- If the color deepens to a more purple or violet shade: Vascular dark circles. The stretching spreads the skin thinner and makes the blood vessels even more visible.
- If the darkness improves or disappears entirely: Structural dark circles. You were seeing a shadow cast by the tear trough, and stretching the skin eliminates that shadow.
This isn’t a clinical diagnosis, but it gives you a useful starting point for choosing the right approach.
What Helps Each Type
Because the causes differ, treatments that work for one type can be completely useless for another.
For Pigmented Dark Circles
Topical ingredients that target melanin production are the main approach. Vitamin C, niacinamide, and products containing gentle exfoliating acids can gradually lighten excess pigmentation over weeks to months. Sun protection matters here more than anywhere else on the face, since UV exposure is one of the primary triggers for melanin overproduction in the periorbital area.
For Vascular Dark Circles
Caffeine and vitamin K are the two most studied topical ingredients for this type. Caffeine constricts blood vessels, stimulates local blood circulation, and acts as an antioxidant. Vitamin K strengthens capillary walls and reduces the visibility of blood vessels beneath the skin. One study using 1% vitamin K combined with a low concentration of retinol found improvement in 93% of patients. Eye creams combining caffeine (around 3%) with vitamin K (around 1%) target both the leaky vessels and the sluggish circulation that contribute to that purple hue.
For Structural Dark Circles
Topical creams can’t fill in a hollow. Structural dark circles caused by tear trough deformity are typically addressed with injectable hyaluronic acid fillers, which restore lost volume beneath the skin and eliminate the shadow. These fillers need to be placed deep, at the level of the bone or just above it. When injected too superficially, hyaluronic acid can cause a complication called the Tyndall effect: a visible bluish discoloration under the skin, caused by the filler scattering blue light. This essentially replaces one type of dark circle with another, so practitioner experience matters significantly with tear trough treatments.
For Mixed Dark Circles
A layered approach works best. Someone with both vascular discoloration and a deep tear trough might benefit from a caffeine-based eye cream combined with filler. Someone with pigmentation and thin skin might use a brightening serum alongside diligent sunscreen use. The stretch test helps you prioritize which component to address first.
Why They’re So Stubborn
Dark circles are notoriously difficult to eliminate for a few reasons. The periorbital skin is only about 0.5mm thick, making it one of the most transparent areas on the body. You can’t meaningfully thicken it. Aging continuously reduces the fat and collagen that once padded the area, so structural shadows tend to worsen over time regardless of treatment. And melanin deposition, once established in the deeper layers of skin, is slow to reverse.
The daily fluctuation in appearance adds another layer of frustration. Research on patients with confirmed dermal melanin deposits found that their dark circles still looked noticeably different from morning to evening, influenced by fluid shifts, fatigue, and blood flow changes throughout the day. This means even a well-treated case of periorbital hyperpigmentation will look worse on some days than others, and that’s normal biology rather than treatment failure.