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Long-acting beta-2 agonist (LABA) bronchodilator

Formoterol: uses, side effects & precautions

Also known as Oxis, Foradil, Atimos, Symbicort (with budesonide), Fostair (with beclometasone).

Esta información es solo orientativa de carácter general y no constituye un consejo médico. Consulta siempre a un profesional sanitario cualificado para cualquier asunto médico personal. En caso de emergencia, llama al número de emergencias de tu zona.

What it is used for

  • Asthma (long-term control, always with a steroid preventer)
  • Chronic obstructive pulmonary disease (COPD)
  • Preventing wheeze and breathlessness
  • In some combination inhalers, used both regularly and for relief under a specific plan

How it works

Formoterol relaxes and opens the airways and keeps them open for many hours. It starts working fairly quickly but lasts a long time, so it is used to prevent ongoing symptoms.

How it is taken

Used as an inhaler, often combined with an inhaled steroid. It is breathed in and taken regularly. In asthma it must always be used with a steroid preventer. Some combination inhalers can also be used for relief under a particular regimen — only do this if your clinician has set it up for you. Use it exactly as directed.

No doses here on purpose. The right strength and schedule depend on you — only a doctor or pharmacist should set them. Always follow your prescription and the label.

Common side effects

  • Shakiness or trembling
  • Fast or pounding heartbeat
  • Headache
  • Muscle cramps
  • Throat irritation

Serious effects — get help

  • Worsening breathing despite regular use (seek urgent review)
  • Chest pain or a very fast/irregular heartbeat
  • Sudden wheeze or breathing difficulty straight after use (seek emergency help)
  • Signs of a severe allergic reaction

If a reaction is severe — for example trouble breathing, swelling of the face or throat, or collapse — go to the nearest emergency room now or call your local emergency number. Do not wait for an online consultation.

Interactions to watch

  • Beta-blockers (can oppose its effect)
  • Some diuretics and other asthma medicines (may affect potassium)
  • Certain antifungal/HIV medicines and some antidepressants

Who should take care

  • In asthma, never use formoterol without a steroid preventer
  • Keep a reliever for sudden symptoms unless your clinician has given you a specific combination-inhaler plan
  • Caution with heart conditions, high blood pressure, an overactive thyroid, or diabetes
  • Tell your clinician if you are pregnant, planning pregnancy, or breastfeeding

Frequently asked questions

How is formoterol different from salmeterol?
Both are long-acting, but formoterol tends to start working faster. This lets some combination inhalers be used both for prevention and relief under a specific plan.
Can I use my formoterol inhaler for relief?
Only if your clinician has set up a combination-inhaler regimen for you. Otherwise, keep and use a separate reliever for sudden symptoms.
Why must it be used with a steroid in asthma?
Long-acting bronchodilators used alone in asthma can be unsafe, so they are always paired with a steroid preventer.
Is the trembling a problem?
Mild shaking and a faster heartbeat are common and usually settle. Report severe or persistent effects to your clinician.
Is Formoterol safe to take?
For most people it is safe when taken exactly as a doctor or pharmacist advises and as printed on the label. Tell your clinician about your other medicines and health conditions, and seek urgent care for any serious reaction.

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