Blood Pressure Medication and Fatigue: What to Know

Why do blood pressure medications cause tiredness?

Antihypertensive medications lower blood pressure through different mechanisms, and the fatigue they cause tends to reflect those mechanisms 1Ref 1Whelton PK, Carey RM, Aronow WS, et al. (2018).2017 ACC/AHA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults.Antihypertensive drug classes and their mechanisms; ACE inhibitors and ARBs as generally better-tolerated for energy levels; beta-blockers as a recognized class with fatigue as a known side effect:

Beta-blockers (metoprolol, atenolol, carvedilol, bisoprolol) are among the most common culprits. They slow the heart rate and reduce the force of each heartbeat. The same effect can leave people feeling low-energy, heavy-limbed, or mentally foggy. Fatigue is one of the most consistently reported side effects of this drug class 2Ref 2Farzam K, Jan A (2023).Beta Blockers.Beta-blockers' fatigue and exercise-tolerance reduction as consistently documented side effects; safety concern with abrupt discontinuation requiring clinician guidance.

Diuretics (hydrochlorothiazide, chlorthalidone, furosemide) cause the kidneys to excrete more sodium and water. Significant fluid loss can lower blood volume enough to produce light-headedness and fatigue, particularly in warmer weather.

Calcium channel blockers (amlodipine, diltiazem, verapamil) can occasionally cause fatigue, particularly at higher doses.

ACE inhibitors and ARBs (lisinopril, enalapril, losartan, valsartan) are generally among the best-tolerated antihypertensives for energy levels, though any medication that lowers blood pressure significantly can reduce energy if blood pressure drops too far 1Ref 1Whelton PK, Carey RM, Aronow WS, et al. (2018).2017 ACC/AHA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults.Antihypertensive drug classes and their mechanisms; ACE inhibitors and ARBs as generally better-tolerated for energy levels; beta-blockers as a recognized class with fatigue as a known side effect.

Could the fatigue be from blood pressure dropping too low?

Yes, and this is worth distinguishing from a direct class side effect. If blood pressure drops below what is comfortable for your body -- called relative hypotension -- you may feel:

• Persistent tiredness or weakness
• Light-headedness when standing up (orthostatic hypotension)
• A feeling of heaviness in the legs
• Difficulty concentrating

This is more likely in the first few weeks after starting or increasing a medication, in people who are physically active, or in older adults. A home blood pressure log, taken morning and evening, can help your clinician determine whether the fatigue corresponds to readings below your target range 3Ref 3Muntner P, Shimbo D, Carey RM, et al. (2019).Measurement of Blood Pressure in Humans: A Scientific Statement From the American Heart Association.Home blood pressure monitoring as a useful clinical tool for assessing medication effect and detecting relative hypotension contributing to fatigue.

How long does the tiredness usually last?

It depends on the cause. If the fatigue is from beta-blocker-related slowing of the heart, it often persists as long as you take the medication, though many people adapt to some degree over the first several weeks 2Ref 2Farzam K, Jan A (2023).Beta Blockers.Beta-blockers' fatigue and exercise-tolerance reduction as consistently documented side effects; safety concern with abrupt discontinuation requiring clinician guidance. If it is from blood pressure running too low, it often improves once the dose is adjusted.

Fatigue that appears within the first two to four weeks and then gradually fades is common with most antihypertensives. Fatigue that is severe, worsening, or interfering significantly with daily life after several weeks warrants a direct conversation with your clinician.

Are there blood pressure medications less likely to cause fatigue?

Generally speaking, ACE inhibitors (lisinopril, enalapril, ramipril) and ARBs (losartan, valsartan, olmesartan) tend to have the most favorable side effect profiles for energy levels. They work by blocking hormones that constrict blood vessels rather than directly slowing the heart 1Ref 1Whelton PK, Carey RM, Aronow WS, et al. (2018).2017 ACC/AHA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults.Antihypertensive drug classes and their mechanisms; ACE inhibitors and ARBs as generally better-tolerated for energy levels; beta-blockers as a recognized class with fatigue as a known side effect.

If you are on a beta-blocker specifically for hypertension (rather than for a heart rhythm issue or heart failure), your clinician may consider whether a different class would achieve similar blood pressure control with fewer energy-related side effects. This is always a clinician decision -- stopping a beta-blocker abruptly is not safe 2Ref 2Farzam K, Jan A (2023).Beta Blockers.Beta-blockers' fatigue and exercise-tolerance reduction as consistently documented side effects; safety concern with abrupt discontinuation requiring clinician guidance.

Some people find that taking beta-blockers in the evening rather than the morning reduces daytime sedation. Ask your clinician whether the timing of your specific medication can be adjusted.

What else could be causing the tiredness?

It is easy to attribute fatigue entirely to a recently started medication, but other contributing factors are worth considering:

• Sleep quality: Many people with hypertension also have obstructive sleep apnea, which itself causes profound daytime fatigue independent of medication.
• Iron, vitamin B12, or thyroid: Deficiencies in any of these are common causes of fatigue that can appear at any time.
• Depression: Low mood and fatigue often overlap.
• Dehydration or electrolyte shifts: Particularly relevant with diuretics.

Your clinician can order basic bloodwork to check these possibilities if fatigue is significant or persistent.

What to bring to your next appointment

Before changing or stopping any medication, a conversation with your clinician is essential. It helps to come prepared with:

• A log of your blood pressure readings at home, morning and evening, over the past week
• A description of when the fatigue is worst (morning, afternoon, after exertion, upon standing)
• Any other new symptoms (dizziness, swelling, shortness of breath, irregular heartbeat)
• A list of all medications and supplements you are taking

A Gale primary care clinician can review your medication, your readings, and your symptoms together and help determine whether a dose adjustment, medication change, or further evaluation makes sense.