Only a handful of eye drop types can noticeably shift blood pressure or heart rate, and they don’t all push in the same direction. Beta-blocker glaucoma drops such as timolol, and the glaucoma drop brimonidine, tend to lower pressure and pulse. Dilating drops (phenylephrine) and some redness-relief drops can briefly raise blood pressure. A drop doesn’t stay in the eye. Much of it drains through the tear duct into the nose and gets into the bloodstream from there, so a medicine meant for the eye can act on the heart and blood vessels much like a pill would. Common everyday glaucoma drops such as latanoprost and dorzolamide show no measurable effect, and for most healthy adults the changes are small. They matter more for people with heart or lung problems, people on blood pressure pills, and young children.
How Eye Drops Reach Your Heart and Blood Vessels
Up to 80% of a drop placed in the eye can end up in the bloodstream, mostly through the blood-rich lining of the nose.1The Open Ophthalmology Journal. A Single Drop in the Eye – Effects on the Whole Body? Medicine absorbed there skips the liver, which normally breaks down part of any pill before it reaches the rest of the body.2The Open Ophthalmology Journal. A Single Drop in the Eye – Effects on the Whole Body? So a tiny eye drop can reach the heart and blood vessels at a strength that matters.
If you taste the medicine at the back of your throat after a drop, it has drained into your nose and throat. A runny nose or swallowing right after drops points the same way: some of the dose is being absorbed. The eye holds only a small fraction of one drop, so bigger or repeated drops just send more down that route.
Beta-Blocker Glaucoma Drops Like Timolol Lower Pulse and Blood Pressure
Timolol and betaxolol belong to the beta-blocker family, the same family as some heart and blood pressure pills, which slow the heart and relax its pumping. Timolol drops slowed resting heart rate after the very first dose, and with ongoing use they kept holding down the heart’s top rate during exercise.3PubMed. Cardiovascular effects of ophthalmic timolol They also lowered blood pressure during exercise more than several other glaucoma drops.4PubMed. The cardiovascular, pulmonary, and ocular hypotensive effects of 0.2% brimonidine If you feel unusually tired or short of breath on exertion after starting timolol, this effect may be the reason.
The effect also shows up at night and with long-term use. People using beta-blocker drops had larger nighttime drops in blood pressure and a lower nighttime pulse than people not using them.5PubMed. Beta-blocker eyedrops and nocturnal arterial hypotension After 3 months on betaxolol drops, pulse and blood pressure readings were lower.6PubMed. Effects of latanoprost and betaxolol on cardiovascular and respiratory status of newly diagnosed glaucoma patients Older adults starting betaxolol should have pulse and blood pressure checked before starting and at regular intervals after.7PubMed. Effects of latanoprost and betaxolol on cardiovascular and respiratory status of newly diagnosed glaucoma patients
Some signs suggest a beta-blocker drop may be slowing your heart too much. Dizziness or lightheadedness when you stand up can reflect low blood pressure. Unusual fatigue or less stamina on walks or stairs may mean a slowed pulse. Wheezing or breathlessness can mean the drop is affecting your airways. Fainting or near-fainting needs prompt medical attention.
Checking your pulse at home is easy. Sit quietly for a few minutes, place two fingers on the inside of your wrist below the thumb, count beats for a full 30 seconds, and double the number to get beats per minute. Check at about the same time each day, such as before your morning drop, so any change after a new drop stands out. A home cuff on the upper arm gives blood pressure readings you can write down with the pulse and bring to appointments. A pulse much lower than your usual, or one that comes with dizziness or fainting, is worth sharing with your doctor promptly rather than at the next scheduled visit.
Timolol is not suitable for everyone:
- People with asthma or a history of asthma8U.S. Food and Drug Administration. Timolol GFS
- People with severe COPD9U.S. Food and Drug Administration. Timolol GFS
- People with a slow heart rhythm or certain heart blocks10U.S. Food and Drug Administration. Timolol GFS
- People with uncontrolled heart failure or cardiogenic shock11U.S. Food and Drug Administration. Timolol GFS
Brimonidine Can Lower Blood Pressure, While Most Other Glaucoma Drops Don’t
About 4 hours after a dose, brimonidine lowered resting systolic (top number) blood pressure by about 5 to 7 points more than other drops.12PubMed. The cardiovascular, pulmonary, and ocular hypotensive effects of 0.2% brimonidine Compared with a placebo drop, it lowered both blood pressure and heart rate.13PubMed. A comparison of the short-term hypotensive effects and side effects of unilateral brimonidine and apraclonidine in patients with elevated intraocular pressure Apraclonidine, a close relative used mainly around eye laser treatments, did not change blood pressure or pulse more than a placebo.14PubMed. A comparison of the short-term hypotensive effects and side effects of unilateral brimonidine and apraclonidine in patients with elevated intraocular pressure
A drop of a few points in systolic pressure often goes unnoticed in people whose pressure runs high. It may cause lightheadedness in people whose pressure is already low or who take blood pressure pills. Sleepiness is a recognized effect of brimonidine. If you feel dizzy after a dose, standing up slowly gives your body time to adjust.
Several common drops appear neutral. Latanoprost, a widely used once-nightly drop, caused no meaningful changes in blood pressure or pulse over 3 months.15PubMed. Effects of latanoprost and betaxolol on cardiovascular and respiratory status of newly diagnosed glaucoma patients Dorzolamide drops left blood pressure and heart rate unchanged during treatment.16PubMed. Effect of topical dorzolamide on optic nerve head blood flow They also avoid the serious whole-body side effects of the pill form of the same kind of medicine.17PubMed. Dorzolamide. A review of its pharmacology and therapeutic potential in the management of glaucoma and ocular hypertension
Knowing which drop you use comes first. Combination drops may contain timolol alongside another medicine even when timolol isn’t in the brand name. Bring all your bottles to appointments so the doctor sees every ingredient. Newer drops like netarsudil have little published data on blood pressure, so ask if you’re unsure.
If you’ve had dizziness, a slow pulse, or breathing trouble since starting a drop, tell your eye doctor. They can weigh switching you to a drop with less effect on the heart. Never stop a glaucoma drop on your own, because eye pressure can rise without any symptoms.
Dilating Drops at the Eye Doctor Can Briefly Raise Blood Pressure
Phenylephrine 10% drops raised blood pressure by about 15 points on average at 5 and 10 minutes.18PubMed. Cardiovascular Adverse Effects of Phenylephrine Eyedrops: A Systematic Review and Meta-analysis By 20 to 30 minutes, readings were back to where they started.19PubMed. Cardiovascular Adverse Effects of Phenylephrine Eyedrops: A Systematic Review and Meta-analysis The weaker 2.5% strength showed no meaningful heart rate effects and only a brief blood pressure rise.20PubMed Central. A Single Drop in the Eye – Effects on the Whole Body?
Most people aren’t affected. With 10% drops, 87% of people with normal blood pressure and 76% with high blood pressure had no significant rise.21PubMed Central. Effect of 10% Phenylephrine Eye Drops on Systemic Blood Pressure in Normotensive & Hypertensive Patient A mild rise occurred in 11% of people with normal and 15% with high blood pressure, and 3% of those with high blood pressure had a severe rise.22PubMed Central. Effect of 10% Phenylephrine Eye Drops on Systemic Blood Pressure in Normotensive & Hypertensive Patient So people with high blood pressure are a bit more likely to react, which is worth mentioning before dilation.
Atropine drops mostly affect rhythm, not pressure. They did not change blood pressure or heart rate compared with a placebo.23PubMed. Systemic absorption of topically applied ocular atropine In rare reported cases after eye surgery, though, atropine drops were linked to irregular, racing heart rhythms.24PubMed. Cardiac dysrhythmias associated with ophthalmic atropine In children under anesthesia, phenylephrine drops combined with atropine through a vein sharply raised blood pressure.25PubMed Central. Adverse Cardiovascular Effects of Phenylephrine Eye Drops Combined With Intravenous Atropine
When someone does notice the rise, it can show up as a pounding headache, a racing heartbeat, or feeling flushed or jittery. If you feel unwell, tell the staff right away so they can check your blood pressure.
Before your dilated exam, tell the staff if you have high blood pressure, heart disease, or recent heart problems. Take your usual blood pressure pills that day unless told otherwise.
Strength is a fair thing to ask about. Phenylephrine comes in more than one strength, and the weaker 2.5% is usually enough, so ask which one the office uses. Offices choose based on the eye, such as how well the pupil widens, so some people may still need the stronger drop. If your blood pressure is poorly controlled or you’ve had a recent heart event, the doctor can weigh the weaker strength or a different plan.
Are Redness-Relief Drops Safe With High Blood Pressure
Redness-relief drops work by narrowing the tiny blood vessels on the eye’s surface. In studies, side effects were mild and short-lived, with no significant whole-body effects.26PubMed Central. Over-the-Counter Ocular Decongestants in the United States – Mechanisms of Action and Clinical Utility for Management of Ocular Redness Reports to the FDA about oxymetazoline drops, also sold for droopy eyelids, do include some cases of high blood pressure.27PubMed. Safety Analysis of Oxymetazoline Eye Drops for Blepharoptosis Using the FDA Adverse Event Reporting System Risks go up with overuse, in children, and in people with heart disease or on certain medicines.28Dulles Eye Associates. The Real Danger of Red Relief Eye Drops
The same vessel-narrowing action that clears the eye’s surface can, once absorbed through the nose, narrow blood vessels elsewhere and nudge blood pressure upward. Frequent use makes this more likely, because repeated doses keep adding medicine to the bloodstream. People taking certain medicines, such as older antidepressants called MAO inhibitors, have extra reason to ask a pharmacist before using these drops.
Ingredients differ between products. Some newer redness drops contain a very low dose of brimonidine, while older ones use stronger vessel-narrowing ingredients. The “Drug Facts” box carries warnings about high blood pressure or heart disease, so read it.
With high blood pressure, use only the labeled number of drops and for a few days at most. Daily use can cause rebound redness that tempts you to use even more. Check the active ingredients for tetrahydrozoline, naphazoline, oxymetazoline, or brimonidine, and ask a pharmacist for lubricating drops without blood-vessel-narrowing ingredients.
When Eye Drops Combine With Blood Pressure Pills
Blood pressure pills are the medicines most likely to interact with beta-blocker drops, including diuretics, ACE inhibitors, calcium channel blockers, and beta-blocker pills.29Review of Optometry. Interactions with Glaucoma Meds People on timolol drops who also took beta-blocker pills had bigger blood pressure changes and a slower pulse.30PubMed. Effects of systemic beta-blocker therapy on the efficacy and safety of topical brimonidine and timolol They also got less eye pressure lowering from the drops.31PubMed. Effects of systemic beta-blocker therapy on the efficacy and safety of topical brimonidine and timolol So tell your eye doctor about every heart and blood pressure pill you take.
Your family doctor or cardiologist may not know about your eye drops. Bring a medicine list that includes drops to every visit.
Warning signs that drops are adding to pills include dizziness when standing, unusual tiredness, a pulse that feels very slow, fainting, or shortness of breath on mild effort. These can appear soon after starting a drop or after a dose change of a heart or blood pressure pill, so timing is a clue worth reporting.
Surgery is another time this matters. Eye drops can add to blood pressure drops during anesthesia. One man on timolol and pilocarpine drops developed a slow pulse and low pressure under anesthesia. Tell the anesthesia team about your eye drops before any operation.
How to Cut the Amount That Reaches Your Bloodstream
Pressing the inner corner of the eye to block the tear duct lowers how much medicine reaches the bloodstream.32PubMed. Review: Systemic Absorption of Topically Applied Ocular Drugs in Humans Gently closing the eyes after a drop has a similar effect and helps more medicine get into the eye.33PubMed Central. The Importance of Eyelid Closure and Nasolacrimal Occlusion Following the Ocular Instillation of Topical Glaucoma Medications, and the Need for the Universal Inclusion of One of these Techniques in All Patient Treatments and Clinical Studies Pressing the corner is often done poorly, though.34PubMed. New technique to reduce systemic side effects of timolol eye drops: The tissue press method-Cross-over clinical trial Very small, precise doses delivered by new devices lowered blood levels of phenylephrine without losing effect.35PubMed. High-precision piezo-ejection Ocular microdosing: Phase II Study on Local and Systemic Effects of Topical Phenylephrine
A good routine goes like this: wash your hands, tilt your head back, pull down the lower lid, and place one drop. Close your eyes gently, without squeezing or blinking hard. Press a fingertip or tissue on the inner corner by your nose for about 1 to 2 minutes. Wipe away extra liquid instead of letting it run down your face. If you need a second drop, wait about 5 minutes.
Some mistakes undo the benefit. Using two or three drops when one is enough sends the extra down the tear duct. Blinking rapidly pumps medicine into it. And pressing on the eyeball rather than the corner by the nose does nothing for absorption.
Why Children and Pregnant People Need Extra Caution
Two young children under 4 became repeatedly unable to be woken after brimonidine drops, and others had extreme fatigue.36PubMed. Safety and efficacy of brimonidine in children with glaucoma Symptoms cleared once the drops stopped.37PubMed. Safety and efficacy of brimonidine in children with glaucoma In one group of children, about 1 in 4 had to stop brimonidine due to side effects, including tiredness and fainting.38PubMed. Ocular and systemic side effects of brimonidine 0.2% eye drops (Alphagan) in children Brimonidine can also be life-threatening if a young child swallows it or gets too much.39PubMed Central. Brimonidine Eye Drops within the Reach of Children: A Possible Foe Store it, and all eye drops, out of children’s reach. A child’s body is small, so the same drop delivers a proportionally larger dose than it would in an adult.
Parents should watch for unusual sleepiness, floppiness, or hard-to-wake behavior after drops. Slow or shallow breathing needs emergency care. If a child swallows any eye drop, call poison control right away.
Pregnancy brings its own cautions. Most glaucoma drops carry an older FDA rating meaning risk to the baby can’t be ruled out, while brimonidine had a lower-risk rating.40PubMed Central. A Single Drop in the Eye – Effects on the Whole Body? Tell your eye doctor if you are pregnant or planning to be.