Sunken eyes result from volume loss in the fat, bone, and soft tissue surrounding the eye socket. The most common cause is natural aging, but dehydration, significant weight loss, genetics, allergies, certain medications, and underlying medical conditions can all play a role. Understanding which factor is behind the change helps determine whether it’s cosmetic, temporary, or worth investigating further.
How Aging Reshapes the Eye Area
The area around your eyes is one of the first places to show age, and the changes go deeper than skin. Starting in your 30s and 40s, three things happen simultaneously: the fat pads cushioning your eye socket shrink, the bone of the eye socket itself slowly widens through a process called resorption, and the skin covering it all gets thinner as collagen breaks down faster than your body can replace it.
The fat loss is measurable. Comparing women to their daughters (an average age gap of 28 years), researchers found roughly 0.8 cc of fat volume disappears from the upper and inner portions of the orbit alone. That may sound small, but in an area as delicate as the under-eye, it’s enough to reveal the underlying bone and muscle. The result is a deeper groove between the lower eyelid and cheek, known as the tear trough, along with a hollowed, shadowed look that makes eyes appear smaller and more recessed.
The ligaments holding everything in place also loosen over time, allowing tissue to shift downward. Meanwhile, the orbital rim widens, giving the eyeball more room to settle backward. Doctors call this age-related recession “senile enophthalmos,” and it’s the combined effect of fat atrophy, bone changes, and ligament stretching rather than any single factor.
Weight Loss and “Ozempic Face”
Rapid or significant weight loss doesn’t just slim your body. It strips fat from the face in predictable areas: the temples, cheeks, and the tissue surrounding the eyes. The hollowed-out look that follows has been widely discussed in connection with GLP-1 medications like semaglutide, sometimes called “Ozempic face,” though the same thing happens with any substantial fat loss, including after bariatric surgery.
When facial fat shrinks quickly, the skin doesn’t have time to contract along with it. The tear trough deepens, wrinkles become more prominent, and the periorbital area looks sunken. This effect is more dramatic in people over 40 who already have some age-related volume loss, because the weight loss compounds changes that were already underway.
Genetics and Facial Structure
Some people have naturally deep-set eyes that aren’t caused by aging or illness. The tear trough is a concave feature determined in part by inherited anatomy: the shape of your cheekbone, the position of your orbital rim, and how much fat sits beneath the muscle around your eye. If you have a naturally flat midface or less prominent cheekbones, the groove between your lower lid and cheek will be more visible from a young age.
The depth of the tear trough also correlates with the tightness of a specific ligament that anchors the skin to the bone beneath the eye. In people where this ligament creates a sharper attachment point, the hollow appears as a V-shaped groove even without significant fat loss. This is purely structural and runs in families.
Dehydration and Sleep Deprivation
Unlike the causes above, dehydration produces a temporary sunken appearance. When your body is low on fluids, the skin under your eyes (already the thinnest skin on your body) loses what little plumpness it has. The tissue sits closer to the underlying bone, creating shadows that mimic the look of deeper structural volume loss. Illness-related dehydration, heavy alcohol use, and not drinking enough water throughout the day can all trigger this.
Sleep deprivation works through a similar visual mechanism. Poor sleep dilates blood vessels beneath the thin under-eye skin, creating dark circles, while fluid shifts make the area look more hollow. A few nights of good sleep and adequate hydration typically reverse this kind of sunkenness completely.
Allergies and Nasal Congestion
Chronic nasal allergies can make the under-eye area look dark and hollow, a phenomenon sometimes called “allergic shiners.” The mechanism is vascular: when your nasal passages are swollen and congested, they obstruct the veins that drain blood from the lower eyelid and tear duct region. Blood pools in those small veins, creating a bluish-purple discoloration beneath the eyes that deepens their apparent hollowness. Managing the underlying allergy or congestion resolves the discoloration.
Glaucoma Eye Drops
A less well-known cause is a class of eye drops commonly prescribed for glaucoma. These drops (which include bimatoprost, travoprost, and latanoprost) work by lowering eye pressure, but they also inhibit fat cell growth around the eye socket. Over months of daily use, the orbital fat gradually atrophies, giving the treated eye a noticeably sunken appearance compared to the untreated eye. This is recognized as a class-wide side effect, with bimatoprost carrying the highest risk and latanoprost the lowest. If you use glaucoma drops and notice one eye looking more hollow than the other, that’s worth raising with your eye doctor.
Orbital Fractures and Sinus Conditions
Trauma to the face can cause the thin bone forming the floor of the eye socket to fracture. When this happens, orbital fat herniates downward into the sinus cavity below, increasing the effective volume of the socket and allowing the eyeball to sink backward. This is one of the most common causes of true enophthalmos, where the eye itself is displaced, not just the surrounding tissue.
A condition called silent sinus syndrome produces a similar result without any injury. Chronic inflammation in the maxillary sinus (the large sinus beneath your cheekbone) causes the sinus wall to slowly bow inward, gradually pulling the orbital floor down with it. Because this happens over months or years with few obvious symptoms, people sometimes notice the sunken eye before they’re aware of the sinus problem. It typically affects only one side.
Other Medical Causes
Several less common conditions can produce sunken eyes. Systemic fat loss disorders (lipodystrophy) reduce fat throughout the body, including around the orbits. Parry-Romberg syndrome causes progressive shrinkage of tissue on one side of the face. Localized scleroderma can cause fibrosis and contraction of orbital tissues. Certain craniofacial syndromes present from birth, such as Treacher-Collins or Crouzon syndrome, involve underdeveloped cheekbones that make the eyes appear recessed.
Metastatic cancer that reaches the orbit can also cause the eye to retract, as can scarring from radiation therapy or prior eye surgery. These are rare but represent cases where sunken eyes signal something that needs medical attention, particularly if the change is sudden, affects only one eye, or comes with vision changes.
Treatment Options and What to Expect
For age-related or weight-loss-related hollowing, hyaluronic acid filler injected into the tear trough is the most common non-surgical treatment. The effect lasts longer than many people expect. While the reported average is around 10 to 11 months, 3D imaging studies show measurable volume augmentation lasting over 14 months, and clinical experience suggests visible results can persist up to 24 months in some cases.
The procedure isn’t without risks. The most common side effects are bruising, swelling, and a bluish-gray discoloration called the Tyndall effect, which happens when filler is placed too superficially. Lumps, filler migration, and persistent swelling are possible delayed complications. Rare but serious risks include infection and vascular occlusion, which in extreme cases can affect vision. The under-eye area is technically demanding to inject, so the skill of the injector matters more here than in most filler procedures.
For sunken eyes caused by orbital fractures or silent sinus syndrome, surgical repair of the bone is typically needed. Fat grafting, where fat is transferred from another part of your body to the orbital area, is another option that offers more permanent volume restoration than filler. When the cause is a medication side effect, switching to a different drug or formulation often allows the fat to partially recover over time.