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Atenolol

Heart

Also known as Tenormin

Atenolol is a beta blocker for high blood pressure and chest pain, and it's often prescribed after a heart attack. It blocks adrenaline's effect on your heart, so it beats slower and with less force — which means it needs less oxygen and puts less strain on your blood vessels. Feeling a little tired or sluggish at first is common and usually settles.

How to take it

When

Once a day, at the same time each day.

Food

Works with or without food — take it however suits you, just be consistent.

Avoid

Don't stop suddenly. Missing several doses in a row can trigger chest pain or worse. Refill early and taper only with your doctor.

Good to know

If you have diabetes, atenolol can hide the racing heart that warns you your blood sugar is low.

Missed a dose?

Take it as soon as you remember, unless it's close to your next dose — then skip the missed one. Never double up.

Common side effects

  • Tiredness
  • Cold hands and feet
  • Dizziness or lightheadedness
  • Slow heartbeat
  • Feeling down or low

Call a doctor if

Educational only. This summary is drawn from public FDA labeling and MedlinePlus and simplified for readability. Your prescription label and your pharmacist always come first — doses and instructions vary from person to person.