Blood pressure medication side effects: fatigue, erections and blood values

Blood pressure medication side effects are usually mild, but they rarely arrive alone. For enalapril, reported dry cough sat around 11 percent in trial data (Bangalore, 2010). For a man who trains it feels different: flat energy, heavier sessions, and an erection that no longer shows up on its own.

Most sites file those three complaints under separate articles. In real life they hit you at the same time.

What I mainly want to add here: which blood values can shift on these drugs. Potassium, sodium, creatinine, uric acid and glucose rarely make a side-effect list. They do end up on your result.

And this first, because it is the most important line in the piece. You never stop a prescribed blood pressure drug on your own.

What are the side effects of blood pressure medication?

Commonly reported are dizziness on standing, fatigue, headache and cold hands. The picture differs per class. ACE inhibitors often bring a dry cough, calcium channel blockers swollen ankles, diuretics more trips to the toilet and beta blockers a lower heart rate. Erection problems and lower libido are reported too.

The Dutch Farmacotherapeutisch Kompas describes those profiles per class. Thuisarts explains them in plain language. Those are the two places I check alongside the leaflet.

A side effect is a report, not a law. Plenty of men barely notice anything.

What you feel depends on the drug, the dose and on you.

Which side effect shows up with almost every blood pressure drug?

Feeling dizzy or light-headed when you stand up fast shows up with nearly every class. That makes sense, because they all lower your blood pressure. Your brain notices that drop first when you change position. Fatigue and headache are also widely reported, mostly in the first weeks.

That dizziness says nothing about how well the drug works. It follows from the exact thing you take it for.

Many men notice it eases off when they get up more slowly. If you measure at home, you will see the drop in your numbers too. How to do that reliably sits in our piece on measuring blood pressure at home.

If it keeps going, that is one for your GP.

Blood pressure medication side effects per drug class

Blood pressure drugs are not one thing. Five classes do most of the work. Each has its own familiar complaints, and its own effect on your blood values.

This table puts those two side by side. I built it because I could not find it anywhere.

The table ranks nothing. No class here is better or worse than another.

The table lists generic names, not brand names. Your box may carry a different name while the generic name is the same.

Fatigue, your training and your erection are one picture

Most sites cover sexual side effects or fatigue. For an active man of 40 those two blur together. You sleep the same, you train the same, and everything still drops a notch.

In a review of 15 beta blocker trials, extra fatigue was reported in roughly 1 in 57 treated people per year. For sexual complaints that worked out at roughly 1 in 199 (Ko, 2002).

Those are small numbers. For the man it happens to, it doesn't feel small.

More is usually going on than the drug. High blood pressure itself is linked to stiffer vessels, and that touches your erection as well. Your blood sugar plays a part too, as we explained in diabetes and erection problems.

So the medication doesn't automatically take the blame. It does belong on the table with your GP.

Say it out loud, even when it feels awkward. Embarrassment can hold this conversation back for years, and that costs you more than the conversation does.

Which blood values can change on blood pressure medication?

Diuretics can lower your potassium and sodium and raise your uric acid and glucose. ACE inhibitors and angiotensin receptor blockers can push potassium the other way, upward. They can also raise creatinine shortly after you start, which drops your eGFR. These shifts are often small.

A Cochrane review of thiazide diuretics saw potassium fall and uric acid rise. The effect grew with a higher dose (Musini, 2014). With chlortalidone, glucose rose as well.

Sodium can drop too. In an analysis of reported cases, low sodium showed up around 19 days after starting on average, at a mean value of 116 mmol/l (Barber, 2015). Those are severe cases, not everyday events.

ACE inhibitors and ARBs work differently here. A rise in creatinine of up to about 30 percent in the first two months has been described, and it usually settles afterwards (Bakris, 2000). How large that rise is, and what it means, is your doctor's call.

Take a man of 46 who has been on enalapril for six weeks. His creatinine went from 88 to 104 micromol/l, a rise of 18 percent. His result flags red, and he panics.

Without context that looks like kidney damage. With context it fits a familiar pattern after starting an ACE inhibitor. Only his GP can tell those apart.

What creatinine and eGFR actually say sits in creatinine and eGFR. The Kidney Function test looks at creatinine, eGFR, potassium and sodium among others.

Always tell your doctor which blood pressure drug you take. Without that, a result is missing half its story.

Can blood pressure medication make you gain weight?

Some people gain a little, but it is usually fluid rather than fat. With calcium channel blockers, fluid in your ankles can add half a kilo on the scale. With beta blockers a slight increase is sometimes described, often a few kilos in the first year. Big jumps don't belong to this picture.

That ankle swelling is well studied. In a meta-analysis of 106 trials, 10.7 percent of people on a calcium channel blocker had peripheral edema, against 3.2 percent in the control group (Makani, 2011). After six months that share climbed further.

A tight sock line by the evening is the classic sign.

If you weigh yourself, look at the trend across weeks. One day says little.

What you do instead when side effects hit

The most important part first, and I am repeating it on purpose. You never stop a prescribed blood pressure drug yourself, not even for a few days as a test.

Switching drug or dose is a decision for your GP or pharmacist. They know your whole story, including why you were given this one.

What you can do: write down what you notice, when it started and how bad it is. Two weeks of notes make a consultation far more concrete.

A suspected side effect can be reported yourself to Lareb, the Dutch pharmacovigilance centre. Those reports feed the knowledge everyone else leans on.

Look at the bigger blood pressure picture as well. How much cutting salt really moves the needle sits in salt and blood pressure. The broader story lives in high blood pressure in men.

My view after years of reading men's stories: the side effect nobody discusses is the one that sticks around longest.

Call your GP when a complaint touches your daily life, and take the box with you to the appointment.

References

1. Bangalore S, Kumar S, Messerli FH. Angiotensin-converting enzyme inhibitor associated cough: deceptive information from the Physicians' Desk Reference. Am J Med. 2010;123(11):1016-1030. PMID 21035591.
2. Ko DT, Hebert PR, Coffey CS, Sedrakyan A, Curtis JP, Krumholz HM. Beta-blocker therapy and symptoms of depression, fatigue, and sexual dysfunction. JAMA. 2002;288(3):351-357. PMID 12117400.
3. Makani H, Bangalore S, Romero J, Wever-Pinzon O, Messerli FH. Peripheral edema associated with calcium channel blockers: incidence and withdrawal rate, a meta-analysis of randomized trials. J Hypertens. 2011;29(7):1270-1280. PMID 21558959.
4. Musini VM, Nazer M, Bassett K, Wright JM. Blood pressure-lowering efficacy of monotherapy with thiazide diuretics for primary hypertension. Cochrane Database of Systematic Reviews. 2014;(5):CD003824. PMID 24869750.
5. Barber J, McKeever TM, McDowell SE, Clayton JA, Ferner RE, Gordon RD, Stowasser M, O'Shaughnessy KM, Hall IP, Glover M. A systematic review and meta-analysis of thiazide-induced hyponatraemia. Br J Clin Pharmacol. 2015;79(4):566-577. PMID 25139696.
6. Bakris GL, Weir MR. Angiotensin-converting enzyme inhibitor-associated elevations in serum creatinine: is this a cause for concern? Arch Intern Med. 2000;160(5):685-693. PMID 10724055.
7. Farmacotherapeutisch Kompas. Drug classes in hypertension: ACE inhibitors, angiotensin II antagonists, beta blockers, calcium antagonists and diuretics. 2025.
8. Thuisarts.nl. Information on medication for high blood pressure. 2025.

Disclaimer

This article offers general information and does not replace advice from your GP or pharmacist. Every blood test result includes a professional assessment from a BIG-registered doctor. For treatment decisions, discuss your results with your GP. For sudden or serious symptoms, call your GP, and 112 in an emergency.