High blood pressure (hypertension) is a condition where the force of blood against the artery walls is consistently too high, damaging blood vessels throughout the body. Dry eye syndrome occurs when the eyes do not produce enough tears or when tears evaporate too quickly, causing discomfort, redness, and a gritty sensation. The relationship between hypertension and dry eyes is complex, involving both the disease itself and the medications used to treat it. This connection is traced through the direct impact of high blood pressure on ocular physiology and the side effects of management drugs.
How High Blood Pressure Affects Ocular Health
Chronic, uncontrolled high blood pressure can damage the structures responsible for tear production and the health of the eye’s surface. The persistently elevated pressure contributes to systemic inflammation, including in the eyes. This low-grade inflammation can affect the function of the tear glands and the integrity of the ocular surface.
Hypertension compromises the microvasculature—the small blood vessels that supply the lacrimal glands, which produce the aqueous component of tears. When these vessels become narrowed or blocked, the glands may not receive enough oxygen and nutrients, impairing their ability to produce sufficient tears. Patients with hypertension are more likely to experience dry eye symptoms, and the severity often increases with the stage of the disease.
Antihypertensive Medications and Tear Production
The medications used to treat high blood pressure are often a more direct and common cause of dry eyes than the disease itself. Two classes of antihypertensive drugs are frequently implicated: beta-blockers and diuretics. These medications work differently but can both disrupt the balance of the tear film.
Beta-blockers, such as metoprolol or atenolol, reduce blood pressure by blocking the effects of adrenaline, which can inadvertently reduce tear production. These drugs may lower the level of proteins like immunoglobulin A and lysozyme in the tears, which are necessary for maintaining a healthy tear layer. This reduction in the aqueous component of tears makes the ocular surface more susceptible to dryness and irritation.
Diuretics, often called “water pills,” work by causing the body to excrete excess salt and water, reducing overall fluid volume and lowering blood pressure. This systemic dehydration, caused by drugs like hydrochlorothiazide or furosemide, impacts the body’s fluid balance, including the eyes. With less fluid available overall, tear composition and volume can decrease, directly contributing to dry eye symptoms.
Steps for Relieving Dry Eye Symptoms
Managing dry eyes while treating high blood pressure involves professional guidance and at-home care. If dry eye symptoms appear after starting or changing a blood pressure medication, consult the prescribing physician. They may be able to adjust the dosage or switch to an alternative drug class less likely to cause this side effect. Patients must never stop taking prescribed medication without medical advice.
Non-prescription lubricating eye drops, commonly called artificial tears, provide immediate relief by supplementing the natural tear film. Increasing daily water intake helps counter the dehydrating effects of diuretics and supports overall hydration. Adjusting environmental factors also helps, such as using a humidifier indoors and consciously taking breaks from screens to ensure a regular blink rate.