How Long Do Steroids Stay In Your System?

How long steroids for asthma stay in your system depends on the type of drug you are taking. For example, it can differ whether you're taking an inhaled medication such as Advair (fluticasone and salmeterol) or an oral corticosteroid (e.g., prednisone). A steroid medication's half-life determines how long it circulates in your body.

This article will go over how the half-life of steroid medication works. It also covers what factors might affect how long steroids for asthma stay in your system.

side effects of oral steroids

Hugo Lin / Verywell

What Is the Half-Life of Steroids?

When you take a dose of your medication, the "half-life" refers to how long it takes your body to clear half of the total dose. A medication's half-life determines how often you'll need to take it.

Different types of asthma medications have different half-lives.

Short Half-Life Drugs
  • Eliminated from circulation at a faster rate

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

Long Half-Life Drugs
  • Are actively in circulation for longer periods

  • Longer time between doses

Half-life is mainly related to the properties of the drug, but each person's body is unique. Even if someone takes the same medication at the same dose as you, their body might metabolize it differently.

There are several factors can affect the half-life of a drug, including:

  • Age
  • Sex
  • Body weight and composition
  • Diet and hydration
  • Lifestyle factors (e.g., smoking, substance use)
  • Liver disease
  • Blood circulation
  • Kidney function
  • Other health conditions (e.g., pregnancy)
  • Medications, supplements, and herbal remedies

Steroids Used for Asthma

Oral corticosteroids (sometimes referred to as oral steroids or by a generic name like prednisone) are a group of powerful anti-inflammatory medications.

You might be prescribed steroids if your asthma symptoms are getting worse. You may need to take the drugs for several days to get your symptoms under control.

Updated Guidelines

Many patients with mild persistent asthma are prescribed inhaled steroids to be taken daily to control their asthma symptoms.

Newer guidelines also allow for inhaled corticosteroids to be taken intermittently with a quick acting inhaler when symptoms begin in patients with mild asthma. It is not recommended to stop taking medications used to control your asthma without talking with your physician first. If you have a question about whether you may benefit from a different regimen, talk with your doctor before making changes.

Oral corticosteroids reduce inflammation throughout the entire body (systemic). Inhaled steroids act mostly in the lungs (localized) which reduces the risk of side effects being felt throughout the whole body.

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

Side Effects of Oral Steroids

The most important differences between oral corticosteroids and inhaled steroids is the likelihood of significant side effects.

The side effects of oral steroids include:

Side effects with oral steroids are more likely than side effects with inhaled steroids because of the quantity of steroid taken orally.

Overuse of Oral Steroids

It's important 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 as it should. If this happens, your body may not make steroids well enough during a time of stress and you may need to have them supplemented.

Side Effects of Inhaled Steroids

Inhaled steroids rarely cause systemic side effects like oral steroids. However, you may have local side effects like:

  • Thrush (oral candidiasis)
  • Hoarseness

You can often prevent these side effects 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 you need to take oral corticosteroids more than once per year to control your symptoms, it might be time to look at your asthma action plan with your provider. You should also talk to them about any concerns you have about taking steroids. They can make sure you understand how to safely use the medications as well as give you tips for avoiding side effects.

9 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. Olafuyi O, Parekh N, Wright J, Koenig J. Inter-ethnic differences in pharmacokinetics-is there more that unites than divides? Pharmacol Res Perspect. 2021 Dec;9(6):e00890. doi:10.1002/prp2.890

  2. USADA. Half-Life of a Drug.

  3. Murphy N, Murray PT. Chapter 125: Critical Care Pharmacology. In: Hall JB, Schmidt GA, Kress JP. eds. Principles of Critical Care, 4th ed. McGraw Hill Education; 2014.

  4. American Association for Clinical Chemistry. Pharmacokinetics.

  5. 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

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

  7. Medline Plus. Prednisone.

  8. Nicolaides NC, Pavlaki AN, Alexandra M, Chrousos GP. Glucocorticoid Therapy and Adrenal Suppression.

  9. Institute for Quality and Efficiency in Health Care (IQWiG). Using steroids correctly and avoiding side effects.

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.