Why is a corticosteroid injection administered once every 7 days?

Generally, a corticosteroid injection (commonly known as a "block injection") is administered once every 7 days. This interval may be due to factors such as alignment with the drug's metabolic cycle, adherence to tissue repair patterns, minimizing local tissue irritation, reducing infection risk, and controlling inflammation progression. It is recommended to seek timely medical attention, confirm the diagnosis, and follow a doctor’s guidance for treatment according to the prescribed course. Specific reasons are analyzed below:

1. Alignment with Drug Metabolic Cycle: The medication in block injections typically takes about 7 days to be fully metabolized in the body. Administering another dose at this interval helps maintain an effective drug concentration. After injection, avoid strenuous activity and minimize movement of the injected area to allow the medication to work effectively. Monitor the site for signs of redness, swelling, or increased pain.

2. Adherence to Tissue Repair Patterns: The tissues at the injection site require sufficient time to heal. A 7-day interval allows adequate recovery time and prevents interference with healing caused by overly frequent injections. In daily life, protect the injection site from impact or pressure. Gentle local massage may be appropriate to promote blood circulation and support tissue repair.

3. Minimizing Local Tissue Irritation: Frequent block injections may irritate local tissues, potentially causing edema or adhesions. If mild irritation occurs, topical medications such as diclofenac diethylamine gel, ibuprofen gel, or flurbiprofen gel patches may be used as directed by a physician. Additionally, reduce weight-bearing or stress on the injected area.

4. Reducing Infection Risk: Each injection involves a puncture, and a 7-day interval helps lower the risk of infection associated with repeated needle insertions. Keep the injection site clean and dry after treatment. If signs of infection appear, antibiotics such as cefaclor capsules, amoxicillin capsules, or metronidazole tablets should be used under medical supervision.

5. Controlling Inflammation Progression: Block injections are primarily used to treat localized inflammation. A 7-day interval allows for monitoring the resolution of inflammation and adjusting treatment accordingly, avoiding excessive medication. For severe inflammation, additional oral anti-inflammatory drugs such as celecoxib capsules, etoricoxib tablets, or naproxen sodium tablets may be used under a doctor’s evaluation.

Patients should complete the full course of block injections as prescribed and must not shorten or extend the injection interval without medical advice. During treatment, maintain a light diet and avoid spicy or irritating foods. Closely monitor the recovery of the injection site to support inflammation resolution and tissue healing.