Dexamethasone - Uses, Mechanism Of Action, Pharmacology, Adverse Effects & Contraindications

Summary

Dexamethasone is a powerful corticosteroid used to treat a wide range of conditions, including inflammatory disorders, autoimmune diseases, certain cancers, and respiratory support in premature infants. Its mechanism involves binding to glucocorticoid receptors, leading to anti-inflammatory and immunosuppressive effects. While effective, it carries risks such as immunosuppression, glucose intolerance, and various metabolic and psychiatric side effects. Contraindications include systemic infections, uncontrolled diabetes, and active peptic ulcers. Understanding dexamethasone's benefits and risks is essential for informed patient care.

Takeaways

• 💊 Dexamethasone is a corticosteroid used as a potent anti-inflammatory and immunosuppressant.
• 🩺 It treats a variety of conditions, including inflammatory disorders, autoimmune diseases, and certain cancers.
• 🧠 Dexamethasone reduces inflammation in the brain due to tumors, injuries, or surgery.
• ⚖️ The drug works by binding to glucocorticoid receptors, influencing gene expression to produce anti-inflammatory effects.
• 🔬 Common side effects include immunosuppression, glucose intolerance, and fluid imbalances.
• 📉 Long-term use may lead to osteoporosis, gastrointestinal issues, and psychiatric effects like mood swings.
• 👁️ Dexamethasone can cause ocular side effects such as increased intraocular pressure and cataract formation.
• ⚠️ Contraindications include systemic fungal infections, live vaccines, and active peptic ulcer disease.
• 🧪 Metabolism occurs primarily in the liver, with renal excretion of dexamethasone and its metabolites.
• 🚨 Dexamethasone can also induce serious cardiovascular effects and metabolic changes, requiring careful monitoring.

Q & A

What is dexamethasone and what class of drugs does it belong to?

Dexamethasone is a corticosteroid that possesses potent anti-inflammatory and immunosuppressant properties.

What conditions can dexamethasone be used to treat?

It is used to treat a wide range of conditions including inflammatory disorders, allergic reactions, autoimmune diseases, certain types of cancers, endocrine disorders, nausea from chemotherapy, and to promote fetal lung maturation in premature infants.

How does dexamethasone exert its effects on the body?

Dexamethasone binds to intracellular glucocorticoid receptors, forming a complex that translocates to the cell nucleus to regulate gene expression, enhancing or suppressing the transcription of specific target genes.

What are some common adverse effects of dexamethasone?

Common adverse effects include immunosuppression, glucose intolerance, fluid and electrolyte imbalances, gastrointestinal issues, psychiatric effects, ocular effects, skin changes, weight gain, and muscle weakness.

What are the contraindications for using dexamethasone?

Contraindications include systemic fungal infections, live vaccines, hypersensitivity to dexamethasone, systemic viral infections, active peptic ulcer disease, uncontrolled hypertension, diabetes, ocular herpes simplex, active tuberculosis, and recent myocardial infarction.

What is the mechanism by which dexamethasone increases blood glucose levels?

Dexamethasone alters the expression of proteins involved in glucose metabolism, leading to increased blood glucose levels.

How is dexamethasone administered and how quickly does it act?

Dexamethasone can be administered orally, intramuscularly, or intravenously, with peak plasma concentrations reached within 1 to 2 hours after oral administration.

What effects does dexamethasone have on the immune system?

Dexamethasone suppresses the activity of various immune cells, including T cells and macrophages, and inhibits the production of inflammatory mediators.

What are some potential psychiatric effects associated with dexamethasone use?

Potential psychiatric effects include insomnia, mood swings, anxiety, depression, and cognitive changes such as memory impairment and confusion.

What are the metabolic effects of dexamethasone?

Metabolic effects can include elevated blood cholesterol and triglycerides, glucose intolerance, and the potential for metabolic alkalosis.