Prednisone is a synthetic corticosteroid medication commonly prescribed for its anti-inflammatory and immunosuppressive properties. It is similar to cortisol, a natural hormone produced by the adrenal glands, which plays a role in the body’s stress response and immune system regulation.
How Prednisone Works
Prednisone operates by mimicking the effects of natural cortisol in the body, interacting with glucocorticoid receptors found in many tissues. Once converted to its active form, prednisolone, mainly in the liver, it binds to these receptors within cells. This binding allows the prednisone-receptor complex to enter the cell nucleus, directly influencing gene expression.
A key function of prednisone is its ability to suppress pro-inflammatory genes, reducing the production of inflammatory cytokines, chemokines, and other mediators that contribute to inflammation. It achieves this by inhibiting the activity of specific transcription factors involved in inflammatory responses. Conversely, prednisone also promotes the expression of anti-inflammatory genes, such as those that inhibit enzymes responsible for producing inflammatory substances like prostaglandins. This dual action dampens inflammatory signals and enhances anti-inflammatory processes, making prednisone effective in reducing swelling, pain, and immune system overactivity. Additionally, prednisone affects the distribution of white blood cells, decreasing certain types of immune cells in circulation, which further contributes to its immunosuppressive effects.
When Prednisone is Used for COVID-19
The use of prednisone, or other corticosteroids like dexamethasone, in COVID-19 is primarily reserved for specific, severe presentations. Corticosteroids are generally not recommended for individuals with mild or moderate COVID-19 who do not require oxygen support. Instead, their use is indicated for hospitalized patients experiencing severe COVID-19, particularly those needing supplemental oxygen or mechanical ventilation.
The rationale for using corticosteroids in severe cases stems from the body’s exaggerated immune response, sometimes called a “cytokine storm.” In severe COVID-19, the immune system can overreact, leading to widespread inflammation that damages organs, especially the lungs. Corticosteroids help mitigate this uncontrolled inflammatory response by suppressing pro-inflammatory proteins and reducing the function of various immune cell types.
Evidence from major clinical trials, such as the RECOVERY trial, has supported the use of corticosteroids in severe COVID-19. This landmark trial demonstrated that low-dose dexamethasone reduced 28-day mortality in hospitalized patients who required oxygen therapy or mechanical ventilation. While dexamethasone was the primary corticosteroid studied, other corticosteroids like prednisone and methylprednisolone have similar mechanisms and have also been administered in severe COVID-19 cases. The decision to use prednisone for COVID-19 is guided by clinical criteria and the patient’s overall condition.
Potential Side Effects and Precautions
Prednisone, while effective, can cause a range of side effects, with likelihood and severity increasing with higher doses and longer treatment durations. Common short-term effects include changes in appetite, indigestion, mood alterations, restlessness, and sleep disturbances. Patients may also experience fluid retention, leading to weight gain and a round facial appearance, sometimes called “moon face.”
More serious side effects can occur, particularly with prolonged use. Prednisone can increase blood sugar levels, potentially triggering or worsening diabetes. It also weakens the immune system, raising the risk of bacterial, viral, and fungal infections. Other significant long-term effects include thinning bones (osteoporosis), increased blood pressure, and eye problems such as cataracts and glaucoma. Mood changes, ranging from improved mood to depression, anxiety, and in rare instances, severe psychiatric effects like psychosis, are possible.
Due to these potential side effects, prednisone should only be used under strict medical supervision and with a prescription. Patients should never self-medicate or abruptly stop taking prednisone, as sudden discontinuation can lead to serious health issues, including adrenal gland problems. Healthcare providers carefully weigh the benefits against the risks for each individual, considering their overall health and specific circumstances when prescribing prednisone.