Do Eye Drops Raise BP? The Link Between Ophthalmic Medication and Blood Pressure

October 7, 2025 •

4 min read

It's a misconception that eye drops only affect the eyes; up to 80% of the active ingredient can enter the systemic circulation. This raises the valid concern: do eye drops raise BP? While many drops are safe, certain types containing vasoconstrictors can indeed cause a temporary increase in blood pressure.

Quick Summary

Some eye drops containing vasoconstrictors, like phenylephrine and tetrahydrozoline, can increase blood pressure due to systemic absorption. The risk is higher with certain medications, concentrations, and in at-risk patients, but proper technique can minimize it.

Key Points

Vasoconstrictive drops can raise BP: Eye drops containing ingredients like phenylephrine and tetrahydrozoline constrict blood vessels and can cause a temporary increase in blood pressure due to systemic absorption.
Systemic absorption is the cause: A portion of eye drops drains through the tear duct into the nasal mucosa, entering the bloodstream and bypassing the liver's first-pass metabolism.
Higher concentrations pose a greater risk: The 10% concentration of phenylephrine is more likely to increase blood pressure than the lower 2.5% strength, especially in vulnerable patients.
Glaucoma drops have varying effects: Beta-blocker eye drops (e.g., timolol) can lower blood pressure, while some alpha-agonists may raise it, requiring careful monitoring.
At-risk groups need caution: Individuals with pre-existing hypertension, heart disease, thyroid issues, as well as the elderly and children, are more susceptible to systemic side effects.
Proper technique minimizes risk: Using nasolacrimal occlusion (pressing the inner corner of the eye) and waiting between drops can significantly reduce systemic absorption.

The Mechanism of Systemic Absorption

When you place a drop in your eye, the small tear volume (about 10 µL) means that any excess liquid drains through the nasolacrimal duct into the nasal cavity. This area is highly vascularized, allowing the drug to be readily absorbed into the bloodstream. Unlike medications taken orally, which are first metabolized by the liver, this route of absorption bypasses that process, increasing the concentration of the active ingredient that reaches systemic circulation and potentially causing side effects.

Sympathomimetic Eye Drops: The Primary Culprit

This class of medication includes decongestant eye drops and mydriatics (pupil-dilating drops) that contain sympathomimetic agents. The most common examples are phenylephrine and tetrahydrozoline. These active ingredients work by constricting blood vessels, which is the desired local effect to reduce redness or dilate the pupil. However, this vasoconstrictive effect can become systemic.

Phenylephrine: Studies have shown that phenylephrine eye drops, particularly the higher 10% concentration, can cause a transient increase in blood pressure, especially in at-risk individuals. The lower 2.5% concentration is generally considered safe and poses minimal risk to blood pressure in most patients. Individuals with pre-existing heart problems, hypertension, or hyperthyroidism are most susceptible and should exercise caution.
Tetrahydrozoline (Visine): This is another vasoconstrictor found in many over-the-counter redness relief drops. While systemic absorption from eye drops is less significant than with oral ingestion, it can still cause side effects, including an increase in blood pressure. Severe cases of high blood pressure and other cardiovascular issues have been reported, particularly following misuse or overdose.

Glaucoma Medications: A Mixed Bag

For those with glaucoma, different classes of eye drops can have opposing effects on blood pressure. This highlights the importance of discussing all medications with your ophthalmologist.

Beta-Blockers (e.g., Timolol): These eye drops can be absorbed systemically and have the potential to cause a decrease in blood pressure and heart rate. This is particularly concerning for patients already taking oral beta-blockers, as it can lead to an enhanced, and potentially dangerous, effect.
Alpha-Agonists (e.g., Apraclonidine, Brimonidine): This class of eye drops can cause a variety of cardiovascular side effects, including changes in blood pressure. While some may lower blood pressure, others have been associated with hypertension. Brimonidine, for example, is contraindicated in young children due to the risk of severe systemic effects.

Corticosteroid Eye Drops

Topical steroid eye drops like prednisolone can also have mild systemic effects. Although a significant increase in blood pressure is rare, it is a possible side effect that should be monitored, especially in patients with pre-existing risk factors.

How to Minimize Systemic Risk from Eye Drops

To reduce systemic absorption and the risk of elevated blood pressure, proper administration techniques are crucial.

Practice Nasolacrimal Occlusion: After instilling a drop, use a clean finger to gently press on the inner corner of your eyelid, near the tear duct, for 2 to 3 minutes. This blocks the drainage of the medication into the nasal cavity.
Wait Between Drops: If you need to use multiple drops or different types of drops, wait at least 5 to 10 minutes between applications. This prevents an overflow that could increase systemic absorption.
Don't Overuse: Always follow your doctor’s instructions and avoid excessive use of over-the-counter decongestant drops, which can worsen rebound redness and increase systemic risk.

Comparison of Common Eye Drop Types and Their Effects on Blood Pressure


Eye Drop Type	Common Active Ingredient(s)	Typical Effect on BP	Who is at Risk?
Sympathomimetic	Phenylephrine, Tetrahydrozoline	Can cause a temporary increase in BP, especially at higher concentrations.	Patients with pre-existing heart disease, hypertension, or hyperthyroidism; elderly; children.
Beta-Blocker (Glaucoma)	Timolol, Betaxolol	Can cause a decrease in BP and heart rate.	Patients also on oral beta-blockers; elderly; those with cardiac conditions.
Alpha-Agonist (Glaucoma)	Brimonidine, Apraclonidine	Can cause an increase or decrease in BP; significant systemic effects possible.	Young children; patients with cardiovascular instability or on other medications.
Corticosteroid	Prednisolone	Potential for a mild, systemic BP increase.	Patients with pre-existing risk factors.

Who is Most at Risk?

Some populations face a higher risk of systemic side effects from eye drops, including blood pressure changes. These groups include children, the elderly, and individuals with cardiovascular or other chronic health conditions. Anyone with a history of hypertension, heart disease, or thyroid issues should inform their healthcare provider about their full medication and supplement regimen.

When to Talk to a Doctor

While most eye drops do not significantly affect blood pressure, it is crucial to seek medical advice if you experience symptoms like severe headaches, chest pain, irregular heartbeat, or difficulty breathing after using them. Always discuss your eye drop use with your doctor, especially if you have pre-existing cardiovascular conditions, as safer alternatives or a different treatment approach may be necessary.

Conclusion

The potential for eye drops to affect blood pressure is a real concern, primarily associated with vasoconstrictive agents like phenylephrine and tetrahydrozoline. Systemic absorption via the nasolacrimal duct is the key mechanism. However, by using proper administration techniques and being aware of the specific risks associated with different medication types—including glaucoma and steroid drops—patients can significantly mitigate the risk. It's essential for at-risk individuals to communicate openly with their healthcare provider to ensure that their eye treatment is both effective and safe for their overall cardiovascular health. For the latest approved labeling information on specific medications, you can consult the FDA's database.

Frequently Asked Questions

Yes, Visine eye drops contain tetrahydrozoline, a vasoconstrictor that can be absorbed systemically and cause a temporary increase in blood pressure.

Eye drops with vasoconstrictors, such as phenylephrine and tetrahydrozoline, are the most likely to raise blood pressure, particularly at higher concentrations or with misuse.

Systemic absorption occurs when the medication from eye drops drains through the nasolacrimal duct into the nasal mucosa, where it is absorbed into the bloodstream. This bypasses the liver, increasing the potential for systemic side effects like blood pressure changes.

To prevent systemic absorption, use a technique called nasolacrimal occlusion: gently press on the inner corner of your eye for 2 to 3 minutes after applying the drop. This blocks the drug from entering the nasal cavity.

No, effects vary by medication. Beta-blocker drops (e.g., timolol) typically lower blood pressure and heart rate, while some alpha-agonists may cause fluctuations or an increase.

If you have hypertension or other heart problems, you should use phenylephrine eye drops with caution and under medical supervision. Higher concentrations (10%) are particularly risky, and the lower 2.5% strength is often recommended.

Warning signs include severe headaches, chest pain, nosebleeds, difficulty breathing, or an irregular heartbeat. If you experience these symptoms after using eye drops, seek immediate medical attention.