Cortisone shots deliver a synthetic corticosteroid directly into a targeted area, such as a joint or tendon, to treat pain and inflammation. This localized injection effectively reduces swelling and provides relief for conditions like arthritis or tendonitis. Although the injection is localized, the medication circulates through the body in small amounts. This systemic exposure can lead to temporary side effects, including tiredness or fatigue.
Is Fatigue a Recognized Side Effect
Fatigue is a recognized, usually mild and temporary, systemic side effect following a cortisone injection. Although the primary goal is localized treatment, the corticosteroid is absorbed into the bloodstream, allowing the drug to exert effects beyond the injection site, manifesting as lethargy or unusual tiredness. Local side effects, such as temporary pain or swelling at the injection site, are common and expected. Systemic effects, including dizziness, facial flushing, and fatigue, affect the entire body. This tiredness often begins in the days immediately following the procedure and should pass as the drug is metabolized.
The Adrenal Axis and Energy Regulation
Post-injection fatigue involves the body’s complex feedback system known as the Hypothalamic-Pituitary-Adrenal (HPA) axis. The HPA axis regulates the body’s production of cortisol, a steroid hormone that plays a major role in metabolism, immune response, and energy levels. Cortisone, the drug administered, is a synthetic version of this hormone.
When the body receives this corticosteroid dose, the HPA axis senses the sudden increase in circulating steroid levels. This triggers a negative feedback loop, signaling the hypothalamus and pituitary gland to temporarily halt the production of the body’s own cortisol. This process is known as HPA axis suppression or adrenal suppression.
The temporary dip in natural cortisol leads to symptoms of low energy, generalized weakness, and fatigue. As the synthetic cortisone clears from the system, a temporary lag occurs before the HPA axis fully resumes its normal production rate. This period of reduced cortisol is the physiological basis for temporary fatigue. The extent of this suppression depends on factors like the dose, the specific steroid preparation used, and the frequency of injections.
Duration of Fatigue and When to Contact a Doctor
The fatigue experienced after a cortisone shot is typically short-lived, aligning with the body’s process of clearing the medication and recovering HPA axis function. Tiredness usually peaks within the first one to three days after the injection and resolves completely within a week for most patients.
While fatigue is generally mild, a more serious condition called secondary adrenal insufficiency can occur, especially with repeated injections or higher doses. Immediate medical attention is warranted if the fatigue is extreme, persistent, or accompanied by severe symptoms:
- Persistent vomiting
- Profound muscle weakness
- Dizziness or confusion
- Fever
Patients with diabetes should also monitor their symptoms closely, as corticosteroids can temporarily raise blood sugar levels, which may contribute to tiredness. If symptoms of high blood sugar, such as increased thirst or frequent urination, are noted, contact a healthcare provider. Consulting a doctor is essential if any side effects persist for longer than ten days or worsen over time.