Make sure that you understand when to use this medication and when to use any other asthma medications. For example, sudden asthma attacks should still be treated with a quick-relief inhaler (e.g., short-acting bronchodilators such as albuterol). Do not stop using any of your other asthma medications, even if you feel better after starting formoterol.
Using too much formoterol or using it too often may result in a decrease in drug effectiveness and an increase in serious side effects. Do not use more than the recommended dosage or take this drug more often than prescribed. Do not stop or decrease the dose of other asthma medications (e.g., inhaled corticosteroids such as beclomethasone) without your doctor's approval. If you are using short-acting bronchodilators on a regular schedule (such as every six hours), you should stop taking them while using this drug.
Seek immediate medical attention if you notice any of the following signs of worsening asthma: the usual doses of your asthma medications no longer control symptoms, your quick-relief inhaler is less effective, or you need to use the quick-relief inhaler more often than usual (e.g., more than 4 puffs per day or more than 1 inhaler every 8 weeks). Do not increase your dose of formoterol in this situation.
When used for an extended period, this medication may not work as well and may require different dosing. Talk with your doctor immediately if this medication stops working well.
