Dear Dr. Roach: I’m 58 years old and was diagnosed with high blood pressure back in 2021. Since then, I’ve been prescribed atenolol, which slows down my heart rate. I was later prescribed 10 mg of amlodipine, which I’m told relaxes and dilates my blood vessels.

I wouldn’t say it’s severe, but I never experienced ongoing constipation problems until I started taking these medications (more the amlodipine), which is why I’m hoping that there is a vasodilator without that particular side effect or another medication you can recommend. — M.D.C.

Answer: Atenolol is more likely to cause constipation than amlodipine is, but constipation is certainly possible with either of these medicines. When a prescribed medicine causes a side effect, I usually try to find as close a medicine as possible to the one I am no longer prescribing. But sometimes closely related medicines have closely related side effects.

Drugs that end in “-pine” are a type of calcium channel blocker (felodipine, nifedipine and isradipine), so I would consider trying one of those first to see if that helped and didn’t have the constipation side effect.

Angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) also work by relaxing small blood vessels and are unlikely to cause constipation. I favor those over other medications because the long-term safety and effectiveness data on them for treatment of high blood pressure is excellent.

I sometimes see people treated with hydralazine, a potent vasodilator. This medicine is more often used in people with heart disease (especially heart failure) than in people with high blood pressure and normal heart function. Drug-induced lupus is a major concern with hydralazine, so it is best used when other options aren’t indicated or working..