How Long Do Steroids Stay in Your System?

If you are taking steroids for asthma, you may wonder how long steroids stay in your system. This will vary depending on the type of drug, whether you are taking an inhaled medication such as Advair (fluticasone and salmeterol) or oral corticosteroid (e.g., prednisone), and the characteristics of each medication. Specifically, the drug's half-life will determine how long a drug circulates within your body.

side effects of oral steroids

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Understanding Half-Life

A major factor in how long any drug affects your body is the drug's half-life. In simple terms, the half-life of a drug is the time it takes for half of the drug's dosage to be eliminated from your body.

For example, the half-life of rescue inhalers like albuterol is in the five- to seven-minute range, while the half-life of Advair is five to seven hours.

The half-life of a drug affects several things, including how quickly you'll notice it working and how often you'll need to take it.

Short Half-Life Drugs
  • More concentrated

  • Work faster

  • May need to be dosed multiple times per day to keep blood levels constant

Long Half-Life Drugs
  • Slower to take effect

  • Are actively in circulation for longer periods

  • Longer time between doses

A number of different factors can affect the half-life of a drug, including:

  • Age
  • Sex
  • Hydration
  • Liver disease

While half-life is mostly related to the properties of the drug, each body is unique, which means how a drug is metabolized by your body may differ from how the same drug at the same dosage affects another person.

Steroids Used for Asthma

Oral corticosteroids, sometimes referred to as oral steroids or even by a generic name such as prednisone, are a group of powerful anti-inflammatory medications that are prescribed when you have a significant worsening of your asthma symptoms. They may be used over several days to help get your symptoms under control.

Inhaled steroids, by contrast, are localized to the lungs, which reduces the risk of broader side effects. Although people with asthma routinely have been advised to use an inhaled steroid daily, according to updated recommendations for asthma management by the National Institutes of Health (NIH) issued in December 2020, this no longer is regarded as necessary for those with mild to moderate persistent asthma. If you use an inhaler daily to manage asthma, talk to your healthcare provider about how the new guidelines might affect your treatment.

Half-Lives of Common Asthma Medications
Class Medication Half-Life
Short-acting ß2-agonists salbutamol 4 to 6 hours
Anticholinergic ipratropium bromide  3 to 5 hours
Methylxanthine theophylline 3 to 13 hours
Glucocorticosteroids (inhaled) fluticasone 14 hours
  budesonide 2 to 3 hours
  beclomethasone 15 hours
Glucocorticosteroids (oral/intravenous) prednisone 3 to 4 hours
Long-acting ß2-agonists formoterol 8 to 10 hours
  salmeterol 5.5 hours

Oral corticosteroids are systemic—meaning they reduce inflammation throughout the entire body. Inhaled steroids, on the other hand, act primarily in the lungs.

Side Effects of Oral Steroids

It is helpful to understand the differences between oral corticosteroids and inhaled steroids. The most important of these are related to potential side effects, which may become more pronounced when drug levels are not stable. This can occur when prescription instructions are not followed exactly as directed.

The half-life of oral corticosteroids is significantly longer than inhaled steroids, and therefore oral steroids have a more significant side effect profile, including:

  • Decrease in bone density and possible osteoporosis
  • Cataracts
  • Glaucoma
  • High blood pressure
  • Elevated glucose
  • Aggression and other changes in behavior
  • Increased appetite, fluid retention, and weight gain
  • Increased risk of infection
  • Depression

It is key to mention any recent steroid bursts (the use of a short course of oral steroids) to your healthcare provider. Overuse of oral steroids may prevent your adrenal gland, where your body's natural steroids are made, from working correctly. As a result, your body may not make steroids sufficiently during a time of stress and you may require additional supplementation.

Side Effects of Inhaled Steroids

Inhaled steroids rarely cause these side effects, but do have local side effects that are easily prevented with appropriate steps. Side effects of inhaled steroids are rare but may include:

  • Thrush (oral candidiasis)
  • Hoarseness

These symptoms may be avoided by rinsing your mouth and gargling after using an inhaled steroid, as well as using a spacer device that delivers measured doses.

A Word From Verywell

If your healthcare provider determines you need to take oral corticosteroids more than once per year, it may be time to reexamine your asthma action plan together. Patients and parents of children with asthma often have concerns about the side effects of steroids. Write down any questions and qualms before meeting with your healthcare provider or your child's pediatrician to start a discussion of what's right for you or your child.

4 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Food and Drug Administration. Advair diskus label.

  2. Cloutier MM, Baptist AP, Blake KV, et al. 2020 focused updates to the asthma management guidelines: A report from the national asthma education and prevention program coordinating committee expert panel working group. Journal of Allergy and Clinical Immunology. 2020;146(6):1217-1270. doi:10.1016/j.jaci.2020.10.003

  3. Sharma, S, Chakraborty, RK. Asthma medications. StatPearls.

  4. Health Service Executive. Side effects of corticosteroids.

Additional Reading

By Pat Bass, MD
Dr. Bass is a board-certified internist, pediatrician, and a Fellow of the American Academy of Pediatrics and the American College of Physicians.