What Can I Take to Slow My Heart Rate?

Several options can slow your heart rate, ranging from prescription drugs like beta-blockers and ivabradine to supplements such as omega-3 fatty acids and magnesium, to techniques as simple as slow breathing or drinking cold water. Which approach makes sense depends on whether you need an immediate effect, a modest long-term reduction, or treatment for a diagnosed condition. The picture is more layered than “take this pill,” and some of the most effective strategies do not involve swallowing anything at all.

Prescription Medications

If your doctor has told you your heart rate is consistently too high or you have a condition like atrial fibrillation, heart failure, or chronic angina, prescription medications are the most powerful and well-studied tools. Beta-blockers (metoprolol, atenolol, propranolol, and others) are the workhorses here. They block the effects of adrenaline on your heart, reducing both rate and force of contraction. Calcium channel blockers like diltiazem and verapamil work differently, slowing electrical conduction through the heart. These are standard, well-established drugs that your cardiologist or primary care doctor will choose based on your specific situation.

A newer and more targeted option is ivabradine, which works by a different mechanism entirely. Instead of blocking adrenaline receptors, ivabradine specifically acts on the “funny current,” the electrical signal that sets the pace of your heartbeat in the sinoatrial node. By reducing the steepness of the electrical buildup between heartbeats, it lengthens the pause between beats without affecting how forcefully the heart contracts.¹ Clinical trials have shown that ivabradine decreases heart rate and reduces complications in patients with cardiovascular diseases.² The practical advantage is selectivity: because it targets only heart rate and not blood pressure or heart muscle strength, it can be useful for people who cannot tolerate the blood-pressure-lowering side effects of beta-blockers.

These medications are not available over the counter. If you are asking “what can I take” because your resting heart rate is consistently above 100 beats per minute, or because you feel your heart racing for no obvious reason, that conversation starts with a doctor. Everything that follows covers options you can try on your own, but none of them substitute for medical treatment when a cardiac condition is driving your elevated rate.

Slow Breathing Works Faster Than Most People Expect

You do not need to swallow anything for one of the most reliable heart-rate-lowering techniques available. Deliberately slowing your breathing to about six breaths per minute activates the vagus nerve, the main communication line between your brain and your heart’s braking system. A systematic review and meta-analysis of voluntary slow breathing studies found consistent increases in vagal-mediated heart rate variability both during and after slow breathing sessions.³ In plain terms, slow breathing engages the parasympathetic (“rest and digest”) branch of your nervous system, and your heart rate drops as a result.

The technique is straightforward: breathe in for about four to five seconds, then breathe out for six to seven seconds, and repeat. Research suggests that extending the exhale longer than the inhale amplifies the vagal response.⁴ One study found that a single session of deep, slow breathing significantly boosted vagal tone in both younger and older adults, with the effect being especially pronounced in older participants.⁵

There is one positional caveat worth knowing. While slow breathing in an upright or seated position reliably stimulates vagal activity, doing it while lying flat on your back may shift the balance differently, favoring overall autonomic equilibrium rather than strong vagal dominance.⁴ If your goal is to bring your heart rate down in the moment, sitting up and breathing slowly tends to be more effective than lying down and doing the same thing.

Omega-3 Fatty Acids

Fish oil is probably the most studied supplement for heart rate reduction, and the effect is real, though modest. A meta-analysis of randomized controlled trials published in Circulation found that fish oil supplementation lowered heart rate by about 1.6 beats per minute overall, with the effect climbing to about 2.5 beats per minute in trials lasting twelve weeks or longer.⁶ A later meta-analysis confirmed a similar reduction of roughly 2 beats per minute and found something interesting about which omega-3 does the work: DHA (docosahexaenoic acid) drove the heart-rate reduction, while EPA (eicosapentaenoic acid) alone did not produce a meaningful effect.⁷

Two beats per minute is not going to transform anyone’s health overnight, but the evidence is consistent, the mechanism appears to involve direct effects on cardiac electrical activity, and fish oil is well tolerated at standard doses. If you are shopping for a supplement specifically to nudge your heart rate down, look for one that contains DHA rather than pure EPA. The effect takes weeks to build, not hours, so this is a long-game strategy.

Magnesium, Potassium, and L-Theanine

Magnesium gets a lot of attention in wellness circles as a heart-calming mineral, and there is a grain of truth here. A pilot study found that magnesium supplementation reduced resting heart rate by about 7 beats per minute compared to a control group.⁸ That is a meaningful drop, but it was a small study, and the effect may be most relevant for people who start out low in magnesium. If your magnesium levels are already adequate, adding more may not move the needle. Blood tests are not great at capturing magnesium status either, since most of it lives inside cells rather than floating freely in your bloodstream, which makes it tricky to know where you stand.

Potassium, by contrast, does not appear to help. A meta-analysis of randomized controlled trials concluded that supplementing with 2 to 3 grams of potassium per day is unlikely to affect heart rate in otherwise healthy adults.⁹ Potassium is critical for heart rhythm stability, and dangerously low or high levels can cause serious problems, but adding extra on top of a normal diet does not slow the heart.

L-theanine, an amino acid found naturally in green tea, has a different angle. Rather than acting directly on the heart, it appears to dampen the stress response. In a controlled experiment, people who took L-theanine before a stressful task had lower heart rates compared to those who took a placebo, and the effect seemed to work by dialing down sympathetic nervous system activation, your fight-or-flight wiring.¹⁰ If your heart rate tends to spike because of anxiety or psychological stress rather than an underlying cardiac issue, L-theanine is one of the milder, better-tolerated options to consider. Standard supplemental doses are in the range of 100 to 200 milligrams, roughly the amount in several cups of green tea.

Herbal Remedies With Some Evidence Behind Them

The herbal supplement aisle is full of products claiming to support “heart health,” and most of those claims are vague enough to mean nothing. A few herbs, however, have been studied in controlled trials and show at least preliminary evidence for lowering heart rate.

Hawthorn extract is the most extensively tested. A meta-analysis of eight trials involving over 600 patients with mild-to-moderate heart failure found that hawthorn treatment decreased the pressure-heart-rate product (a measure that combines blood pressure and heart rate) compared to placebo, alongside improvements in exercise capacity and symptoms like fatigue and shortness of breath.¹¹ A separate trial using a high-dose standardized extract showed a stabilizing effect on heart rate, with patients exhibiting a slower resting pulse and more normal rhythm patterns on long-term monitoring.¹² The research on hawthorn is primarily in people who already have heart failure, so applying it to healthy people trying to lower a slightly elevated resting heart rate requires some extrapolation.

Valerian root, better known as a sleep aid, also shows heart-rate effects. A study in healthy volunteers found that valerian tea lowered heart rate over the 30 minutes following ingestion in a time-dependent manner, meaning the effect grew stronger the longer they waited.¹³ The mechanism appears to involve shifting autonomic balance toward vagal (parasympathetic) dominance, similar to slow breathing but triggered pharmacologically.

Motherwort (Leonurus cardiaca) has a long history in European and Chinese traditional medicine for heart complaints. Pharmacological reviews note mild negative chronotropic effects, meaning a gentle slowing of heart rate, along with sedative and blood-pressure-lowering properties, and clinical trials have confirmed these sedative and hypotensive effects.¹⁴ The evidence base is thinner than for hawthorn, and standardized dosing is harder to find, but it is one of the few herbs where the traditional use aligns with measured physiological effects.

Drinking Cold Water

This one surprises people, but drinking cold water can lower your heart rate through a reflex involving temperature-sensitive nerve fibers in your mouth, esophagus, and stomach. When cold water hits those receptors, signals travel up the vagus nerve to the brainstem, which responds by engaging the heart’s parasympathetic braking system.¹⁵ A study specifically examining ice water ingestion confirmed that the heart-rate decrease is driven by this temperature-mediated vagal enhancement.¹⁶

Even plain room-temperature water has a measurable effect. Research comparing water to saline (salt water) found that drinking plain water decreased heart rate and boosted vagal tone, while saline did not, suggesting the response is partly driven by the low salt concentration of the water itself rather than just stomach distension.¹⁷ Cold water appears to add a temperature bonus on top of this osmotic effect. The practical upshot: if you feel your heart racing and want to bring it down in the next few minutes without any pills or special equipment, a glass of cold water is a reasonable first step.

Exercise as a Long-Term Strategy

Regular aerobic exercise is the most well-established way to lower your resting heart rate over time. Endurance training shifts the balance of your autonomic nervous system, increasing parasympathetic (calming) activity and decreasing sympathetic (stimulating) activity at rest. These changes, combined with possible adaptations in the heart’s intrinsic pacemaker rate, produce a lower resting heart rate.¹⁸ Trained endurance athletes commonly have resting heart rates in the 40s or 50s, well below the typical 60 to 80 range.

A systematic review and meta-analysis of exercise interventions confirmed that training reduces resting heart rate, though the magnitude varies with the type, duration, and intensity of the program.¹⁹ You do not need to become an ultramarathoner. Consistent moderate-intensity exercise, such as brisk walking, cycling, or swimming done several times a week for months, produces measurable reductions. The catch is that it takes weeks to months, not days, and the effect reverses if you stop training. This is a lifestyle change, not a quick fix.

When the Usual Advice Gets Flipped

Most advice about heart rate assumes you are trying to bring down a rate that is too high at rest. But for people with postural tachycardia syndrome (POTS), the problem is different: their heart rate spikes dramatically when they stand up, often jumping 30 or more beats per minute within ten minutes. In this population, the treatment approach reverses some of the standard guidance.

For POTS patients, increased salt and fluid intake is a frontline treatment, not something to avoid. Oral salt replacement and aggressive hydration help expand blood volume, which prevents the exaggerated heart-rate surge on standing.²⁰ A study published in the Journal of the American College of Cardiology found that a high-sodium diet reduced the standing heart-rate increase in POTS patients from about 60 beats per minute on a low-salt diet to about 46 beats per minute on a high-salt diet.²¹ Oral rehydration salts have also been used in children with POTS, where they can be effective when the pre-treatment heart-rate increase is at least around 41 beats per minute on standing.²²

The broader point is that the right approach to slowing your heart rate depends entirely on why it is elevated in the first place. A high resting rate from deconditioning calls for exercise. Stress-driven spikes respond to breathing techniques and calming supplements. POTS-related tachycardia calls for salt and fluids. A rate driven by atrial fibrillation or thyroid disease requires specific medical treatment. The “what should I take” question does not have a universal answer.

Safety and Drug-Herb Interactions

Combining heart-rate-lowering supplements or herbs with prescription heart medications is where things can go sideways. Taking hawthorn extract alongside a beta-blocker, for instance, could produce additive effects on heart rate and blood pressure that neither your doctor nor you anticipated. A comprehensive review of herbal cardiovascular effects warned that co-administration of antihypertensive drugs and herbal products with similar mechanisms can cause severe low blood pressure, dangerously slow heart rate, or electrolyte disturbances. Herbs that affect liver enzymes responsible for drug metabolism can also alter how much of a prescription medication ends up in your bloodstream, leading to either too much drug or too little.²³

The practical rule is simple: if you are already on any medication that lowers heart rate or blood pressure, tell your doctor before adding herbal supplements. This includes beta-blockers, calcium channel blockers, ivabradine, digoxin, and certain anti-arrhythmic drugs. Hawthorn, valerian, and motherwort may all be mild on their own, but stacked on top of a prescription drug that already slows the heart, “mild” can become “too much.” Even magnesium supplements can interact with certain heart medications. If you are not on any cardiac medications and are otherwise healthy, the risk profile of these supplements is generally low, but the combination scenario is where the danger lives.

Resting Heart Rate and How Long You Live

People who ask about lowering their heart rate are sometimes motivated by a vague sense that a slower heart is a healthier heart. The research largely supports that intuition. Across mammals as a group, there is an inverse relationship between resting heart rate and lifespan: small animals with fast heart rates tend to live short lives, while larger animals with slower hearts live longer. The total number of heartbeats in a mammalian lifetime is remarkably consistent at roughly 700 million to a billion, regardless of species.²⁴

Within humans specifically, the pattern holds up. A growing body of evidence shows that resting heart rate is inversely related to lifespan, with the connection appearing to reflect both underlying metabolic rate and cardiovascular mortality risk.²⁵ That does not mean artificially forcing your heart rate lower with drugs will extend your life. The relationship is observational, and resting heart rate is at least partly a marker of overall cardiovascular fitness and metabolic health rather than a direct dial you can turn. The interventions that do seem to matter for longevity, regular exercise, stress management, and treating underlying cardiac conditions, happen to lower resting heart rate as a side effect of making the whole system healthier. Chasing a number on a fitness tracker with supplements alone probably misses the point, but using resting heart rate as a signal that your overall fitness could improve is a reasonable way to think about it.