PTCB Guide to Corticosteroids.

What are corticosteroids?

[Last Updated: February 20, 2026]

Corticosteroids are drugs used in the treatment of inflammatory and autoimmune disorders. They are among the most widely prescribed drugs in the United States, with almost 4% of the population receiving a prescription for corticosteroids each year.

Because corticosteroids are widely used in medicine, pharmacy technicians should expect some questions on PTCB exam – either related to identifying these drugs from a list, understanding how they work, or recognizing common side effects and drug interactions.

Corticosteroids can be easily identified because they typically have either the suffix -olone or –sone. For example:

• Prednisolone
• Methylprednisolone
• Dexamethasone
• Hydrocortisone
• Beclomethasone
• Fluticasone
• Betamethasone

There are a few exceptions to this rule, such as budesonide – which is an inhaled corticosteroid used in the management of asthma and COPD.

Recognizing common drug suffixes is valuable because even if you see an unfamiliar medicine on the PTCB exam, the suffix can help you identify its class. For example, recognizing a corticosteroid suffix allows you to associate the drug with inflammatory or autoimmune conditions — which may be enough to select the correct answer with confidence.

Indications – What Corticosteroids are Used to Treat.

Corticosteroids are drugs primarily used in the treatment of inflammatory and autoimmune disorders.

Indications of corticosteroids include:

• Inflammatory bowel disease – Crohn’s disease, ulcerative colitis
• Asthma and COPD
• Arthritis – including rheumatoid arthritis
• Inflammatory skin conditions – such as eczema and dermatitis
• Some cancers – as part of chemotherapy or to reduce swelling
• Optic disorders – such as optic neuritis and uveitis

Of course, this list of indications is not intended to be exhaustive. But it gives you an idea of the broad application of corticosteroid indications in medicine today.

Dexamethasone is also used in cancer chemotherapy to enhance the antiemetic effect (anti-vomiting effects) of 5-HT₃ antagonists such as ondansetron. Dexamethasone and betamethasone are also used to promote fetal lung maturation in preterm labor.

Note that routes of administration with corticosteroids vary. For asthma and COPD, corticosteroids are typically inhaled. For eczema and dermatitis, they are applied topically. Corticosteroids are also available for systemic absorption in the treatment of conditions such as inflammatory bowel disease and cancer.

How do corticosteroids work?

Corticosteroids are synthetic drugs that closely resemble cortisol. Cortisol is a hormone that is naturally produced by the adrenal glands.

Corticosteroids work by entering cells and binding to specific glucocorticoid receptors, which then travel to the cell nucleus and influence gene expression. In other words, corticosteroids upregulate genes that have anti-inflammatory effects and downregulate genes that have pro-inflammatory effects. When it comes to the mechanism of corticosteroids, it’s all about influencing the effects of genes.

As a result, corticosteroids help control symptoms in conditions involving overactive immune responses, such as asthma, rheumatoid arthritis, and lupus. Corticosteroids also suppress immune system activity, making them effective in treating autoimmune diseases and preventing organ transplant rejection.

Side Effects and Significant Warnings.

Corticosteroids are associated with a wide range of side effects, particularly from those drugs that are administered for systemic absorption.

Side effects include:

• Weight gain
• Infections – because they suppress the immune system
• Mood and behavioral disturbances – including anxiety, depression
• Metabolic effects – such as type 2 diabetes and osteoporosis
• Skin thinning and easy bruising
• Increased blood pressure
• Increased risk of cataracts and glaucoma

Note also that corticosteroids are teratogenic and so are avoided in pregnancy.

There are four other warnings worth considering:

• Inhaled corticosteroids can cause oral thrush infection and hoarse voice.
• Because corticosteroids can suppress growth, they should be used with caution in children.
• Because corticosteroids suppress the immune system, they should be used with caution in patients with active infections where they can worsen the infection.
• Drug interactions with inhaled or topical corticosteroids are low because of the relative lack of systemic absorption (i.e. the drug remains largely either within the lungs or on the skin).

Drug Interactions.

Notable drug interactions with corticosteroids include:

• Corticosteroids increase the risk of bleeding when used with NSAIDs.
• Corticosteroids increase the risk of low potassium levels (hypokalemia) in patients taking diuretics, including loop and thiazide diuretics.
• Because corticosteroids suppress the immune system, they reduce the immune response to vaccines.

PTCB Exam-Style Questions.

Below, we put together some practice PTCB exam questions on the topic of corticosteroids; testing the material covered in this tutorial. At the very bottom of this article, you can find the answer to each question. Go through each question first and make a note of your answers.

Question 1.

All these drugs are examples of corticosteroids, except?

a. beclomethasone

b. budesonide

c. methylprednisolone

d. domperidone

Question 2.

What is the primary way corticosteroids reduce inflammation in the body?

a. by blocking histamine receptors on immune cells

b. by increasing antibody production to fight infection

c. by binding to intracellular receptors and altering gene expression

d. by neutralizing toxins produced by pathogens

Question 3.

When used long term, corticosteroids are associated with which side effect?

a. low blood sugar

b. weight loss

c. increased risk of infection

d. increased bone density

Question 4.

Which of these conditions is commonly treated with corticosteroids?

a. asthma

b. type 1 diabetes

c. bacterial infections

d. hypertension

Question 5.

The risk of GI bleeding is increased when corticosteroids are taken with which drugs?

a. antacids

b. NSAIDs

c. statins

d. antihistamines

Answer Explanations.

Answer to Question 1: d. Domperidone

Beclomethasone, methylprednisolone, and budesonide are all examples of corticosteroids. Domperidone is a drug used to treat certain GI disorders as well as nausea and vomiting.

Answer to Question 2: c. By binding to intracellular receptors and altering gene expression

Corticosteroids work by entering cells to influence gene expression within the nucleus of the cell. They upregulate anti-inflammatory genes whilst suppressing pro-inflammatory genes.

Answer to Question 3: c. Increased risk of infection

Corticosteroids suppress the immune system, making it more difficult for the immune system to fight infections or prevent infections from starting. Long-term use of corticosteroids therefore increases the risk of infections.

Answer to Question 4: a. Asthma

Certain corticosteroids are used in the management of asthma and COPD. These drugs include budesonide, fluticasone, and beclomethasone.

Answer to Question 5: b. NSAIDs

NSAIDs increase the risk of gastrointestinal bleeding and peptic ulcer disease. Corticosteroids exacerbate the risk of both when taken with NSAIDs. NSAIDs include drugs such as aspirin, naproxen, and diclofenac.

PTCB Corticosteroids Cheat Sheet.

In review:

• Corticosteroids are drugs used in the treatment of inflammatory and autoimmune disorders.
• Indications include ulcerative colitis, Crohn’s disease, asthma, COPD, eczema, dermatitis, and cancer chemotherapy. Dexamethasone is also used to enhance the antiemetic effect of 5-HT₃ antagonists (such as ondansetron) in patients with cancer.
• Corticosteroids can be easily identified because almost all end with the suffix –lone or –sone. Examples include prednisolone, methylprednisolone, dexamethasone, and betamethasone.
• Corticosteroids work by entering the nucleus of cells and influencing gene expression. They upregulate anti-inflammatory genes whilst suppressing pro-inflammatory genes.
• Side effects of corticosteroids include weight gain, hypertension, infections, type 2 diabetes, cataracts and glaucoma, thin skin / easy bruising, and mood / behavioural changes (anxiety, depression).
• Inhaled corticosteroids can cause oral thrush infection and hoarse voice.
• Corticosteroids can increase the risk of bleeding when taken with NSAIDs. They may cause low potassium levels (hypokalemia) when used alongside diuretics such as loop or thiazide types. Additionally, because they suppress the immune system, corticosteroids can reduce the effectiveness of vaccines by weakening the body’s immune response.
• Corticosteroids can suppress growth and so must be used with caution in children.

We hope that you found this PTCB guide to corticosteroids helpful to your study.

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