Dark circles under the eyes, medically referred to as periorbital hyperpigmentation, are a common cosmetic concern. While often linked to genetics, aging, or lifestyle factors like poor sleep, certain medications can initiate or worsen this discoloration. The skin surrounding the eyes is notably thin, making underlying structures and chemical changes more visible. Understanding the physiological pathways drugs use to affect this delicate area clarifies why they lead to a darkened appearance.
The Biological Basis of Drug-Induced Dark Circles
Medications can lead to dark circles by influencing the skin in three distinct physiological ways. One mechanism involves increasing the visibility of the underlying network of blood vessels, often resulting in a bluish or purplish tint. Since the skin around the eyes is thin, it offers little camouflage for the blood flowing beneath the surface. When blood vessels widen, the deoxygenated blood becomes more apparent through the translucent skin.
Another common pathway is through fluid retention, or edema, which creates a pronounced shadowing effect. When fluid accumulates in the periorbital tissues, the resulting puffiness casts a shadow onto the lower eyelid area. This shadow contributes significantly to the perception of a dark circle, even if the skin is not chemically pigmented. The orbital area has poor lymphatic drainage, making it susceptible to localized fluid accumulation caused by systemic drug effects.
The third mechanism involves true chemical alteration of skin color, known as hyperpigmentation. This involves either the stimulation of melanin production, the natural brown pigment in skin, or the deposition of the drug or its metabolites into the dermal layers. This type of discoloration is generally more persistent and often appears brown, gray, or slate-blue, depending on the chemical deposited.
Medications That Cause Vascular and Fluid Changes
Drug classes that induce vasodilation, the widening of blood vessels, frequently cause or exacerbate dark circles. This effect is noted with certain blood pressure medications, such as nitrates and alpha-blockers like prazosin or doxazosin. By relaxing the smooth muscles in the vessel walls, these drugs increase blood flow, making the underlying venous network more prominent beneath the thin periorbital skin. This increased visibility of deoxygenated blood translates to a noticeable blue or purple discoloration.
Other medications cause dark circles through systemic fluid retention that manifests as periorbital edema. Calcium channel blockers, commonly used to treat hypertension, are known to cause swelling in the extremities, and this fluid can also accumulate around the eyes. Nonsteroidal anti-inflammatory drugs (NSAIDs) may also contribute to fluid retention or trigger hypersensitivity reactions that include localized periorbital swelling. The resulting puffiness creates an anatomical shadow that darkens the infraorbital area.
The chemotherapy agent imatinib is a specific example of drug-induced edema, frequently causing periorbital swelling. The proposed mechanism involves the drug’s effect on capillary permeability, allowing fluid to leak into the interstitial space of the periorbital tissues. This fluid-related discoloration, caused by the physical shadow of the swelling, is typically relieved once the underlying edema is managed or the medication is stopped.
Medications That Alter Skin Pigmentation
The most permanent form of drug-induced dark circles arises from true hyperpigmentation, caused by excess melanin or chemical deposition. Topical prostaglandin analogs, such as latanoprost and bimatoprost, used for glaucoma or eyelash growth, are known for causing periorbital hyperpigmentation. These drops stimulate melanogenesis, the process of melanin production, leading to a visible brownish darkening of the eyelids and surrounding skin. This discoloration usually begins three to six months after starting therapy.
Certain antibiotics and anti-malarial drugs are also associated with discoloration, often through the deposition of the compound itself. The tetracycline-class antibiotic minocycline, used for acne, can cause a blue-gray or slate-gray pigmentation. This occurs when the drug’s metabolites accumulate and bind to tissue components in the dermis, becoming visible through the skin. Similarly, anti-malarial agents like chloroquine and hydroxychloroquine can cause a bluish-gray discoloration, particularly in sun-exposed areas.
Psychotropic medications, specifically phenothiazines like chlorpromazine, are another class linked to chemical deposition. These drugs can induce a progressive, slate-gray or purple discoloration on sun-exposed skin, including the periorbital area. This phenomenon is believed to be caused by drug-melanin complexes or metabolites accumulating in the dermal macrophages. These pigmentary changes are often challenging to reverse, and sun exposure can significantly worsen their severity.
Next Steps and Management
If you suspect a medication is responsible for dark circles, consult with your healthcare provider or prescribing physician. It is not recommended to stop any prescribed medication abruptly, as this could have adverse health consequences. Your provider can evaluate if the dark circles are drug-induced and discuss management strategies, such as dosage adjustment or switching to an alternative agent.
If discontinuing the medication is not medically appropriate, mitigating steps can reduce the visibility of the circles. Strict sun protection is recommended, as ultraviolet light often worsens drug-induced pigmentation. Topical agents containing caffeine, which acts as a local vasoconstrictor, or Vitamin K and Vitamin C, which help stabilize vessel walls and brighten the skin, may offer relief. For true hyperpigmentation, your physician may recommend specialized topical compounds or procedures targeting the excess melanin or deposited metabolites.