Atenolol and Formoterol: Interaction Details
AI-assisted, pharmacist-reviewed · AI content regenerated Jul 15, 2026 · Source data updated Jul 11, 2026 · Sources: FDA labeling, DDInter 2.0, cited literature
Atenolol
Formoterol
How we grade severity & evidence
Severity levels
- Contraindicated: These should generally not be used together.
- Major: Potentially serious — often needs a change or close monitoring.
- Moderate: Can be significant — usually manageable with monitoring.
- Minor: Usually limited clinical impact.
Evidence grades
- Established: Well documented — supported by controlled studies or strong clinical data.
- Probable: Good supporting evidence, though not definitively proven.
- Suspected: Some evidence suggests this interaction, but it is not well established.
- Possible: Limited or conflicting evidence; the interaction may occur.
- Theoretical: Predicted from the drugs' pharmacology; not yet confirmed in people.
Ratings come from the documented interaction literature and are reviewed by a pharmacist. They describe the documented risk of the combination, not what will necessarily happen to you — your dose, timing, and health picture all matter.
These two medicines can work against each other. Formoterol (Perforomist) is a breathing medicine that opens up your airways by switching on receptors called beta-receptors. Atenolol (Tenormin) is a beta blocker that does the opposite by turning those receptors down to lower your heart rate and blood pressure.
Because they pull in opposite directions, atenolol may make your inhaler work less well, and your inhaler could blunt some of the effect of atenolol. This is mostly a theoretical concern, but it matters if you have asthma or COPD. Please don't stop either one on your own. Your doctor or pharmacist can pick the safest option and keep an eye on how you're breathing.
Mechanism: Direct pharmacodynamic antagonism at beta-adrenergic receptors. Formoterol is a long-acting beta-2 agonist (bronchodilator); atenolol is a beta-1 selective (cardioselective) antagonist. Neither is a prodrug, so this is a PD, not PK, interaction.
- Direction: Mutual reduction in efficacy. Beta blockade may attenuate bronchodilation; beta-2 agonism may blunt beta-blocker effect.
- Evidence: Theoretical; severity rated major, especially with reactive airway disease.
- Onset: Unspecified.
- Management: If co-therapy is required, favor a cardioselective agent (atenolol qualifies) at the lowest effective dose with caution. Monitor pulmonary function/symptoms and cardiovascular response; individualize dosing.
What happens
Reduced efficacy of formoterol or reduced efficacy of beta-adrenergic blocker
Interaction Deep Dive
Because of pharmacological antagonism, taking formoterol (a beta-2 agonist) together with a beta-adrenergic receptor antagonist (beta blocker) can cause each drug to counteract the action of the other. When such combined use cannot be avoided or when no suitable alternatives exist, a cardioselective beta blocker should be considered and used cautiously123.
Why it happens (mechanism)
Pharmacological antagonism
How to manage this interaction
Keep taking both as prescribed unless your care team tells you otherwise. Here is how a team usually handles this:
- They may choose a cardioselective beta blocker like atenolol, which is often preferred when a beta blocker is needed alongside an inhaler.
- Your doses may be adjusted and individualized, and your team may monitor your breathing and blood pressure or heart rate more closely.
What to raise with your pharmacist or doctor: tell them if your inhaler seems less effective, if you feel more short of breath or wheezy, or if your blood pressure or heart rate readings change. They can tailor your treatment to keep both medicines working.
Management is individual — confirm any change with your pharmacist or prescriber.
Common questions
Can I take Atenolol and Formoterol together?
Atenolol and formoterol can partly cancel each other out because one blocks beta-receptors and the other activates them. Keep taking both as prescribed and let your doctor or pharmacist know if your breathing or heart readings change so they can adjust and monitor. Always confirm with your pharmacist or prescriber before making any change.
How serious is the Atenolol and Formoterol interaction?
It is rated major. Potentially serious — often needs a change or close monitoring.
How quickly could this interaction happen?
The documented onset is "unspecified". The timing of this interaction is not well characterized.
How is the Atenolol and Formoterol interaction managed?
Keep taking both as prescribed unless your care team tells you otherwise. Here is how a team usually handles this: They may choose a cardioselective beta blocker like atenolol, which is often preferred when a beta blocker is needed alongside an inhaler. Your doses may be adjusted and individualized, and your team may monitor your breathing and blood pressure or heart rate more closely. What to rai… Management is individual — always follow your own care team's guidance.
How strong is the evidence for this interaction?
The evidence is graded "theoretical". Predicted from the drugs' pharmacology; not yet confirmed in people.
Questions for your pharmacist
- Does my dose of Atenolol or Formoterol need adjusting while I take them together?
- What symptoms should prompt me to call you or my prescriber right away?
- Does the timing of my doses matter for this combination?
- Is there a safer alternative to one of these medications for me?
References (3)
- Product Information: PERFOROMIST(R) inhalation solution, formoterol fumarate inhalation solution. Mylan Specialty LP (per FDA), Morgantown, WV, 2017. DailyMed
- Product Information: SYMBICORT AEROSPHERE® oral inhalation aerosol, budesonide formoterol fumarate oral inhalation aerosol. AstraZeneca Pharmaceuticals LP, Wilmington, DE, 2026.
- Product Information: BREZTRI AEROSPHERE® inhalation aerosol, budesonide, glycopyrrolate, formoterol fumarate inhalation aerosol. AstraZeneca Pharmaceuticals LP, Wilmington, DE, 2026. DailyMed
Keep reading about Atenolol
Keep reading about Formoterol
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