07/05/2025
A wrong intramuscular (IM) injection can, in rare but serious cases, lead to paralysis or nerve damage. Here's a breakdown of how this can happen:
1. Nerve Injury
Injecting into or too close to a major nerve — particularly:
Sciatic nerve in the buttock (gluteal region)
Radial nerve in the deltoid region
Femoral or lateral femoral cutaneous nerves in the thigh
Result: Immediate sharp pain, weakness, numbness, or even long-term paralysis in the affected area.
2. Incorrect Site Selection
Using the wrong site (e.g., upper inner quadrant of the gluteal area instead of the upper outer quadrant) increases the risk of hitting a nerve.
3. Improper Technique
Poor technique can cause:
Deep tissue damage
Nerve impingement
Injection too close to bones or blood vessels
4. Toxicity of the Drug
Some medications are not safe if they come in contact with nerve tissue. For example:
Certain antibiotics (e.g., penicillin G)
Irritating substances or oil-based medications
If injected too close to a nerve, they can cause inflammation, demyelination, or necrosis of nerve tissue.
5. Compartment Syndrome or Vascular Compromise
If the injection leads to:
Hematoma
Swelling that compresses nearby nerves
Blocked blood flow to nerves
It can result in temporary or permanent loss of function.
Signs of Injection-Related Nerve Injury:
Burning or shooting pain during injection
Weakness or inability to move the limb
Numbness or tingling
Muscle atrophy (in long-term cases)
What to Do If This Happens:
Immediate medical attention — time is critical.
Neurological evaluation
Imaging (MRI, EMG) to assess nerve damage
Pain management
Physical therapy
Surgery — in severe cases (e.g., nerve repair)
