Causes and Risk Factors of Bell’s Palsy
The exact causes and risk factors of bell’s palsy of Bell’s palsy remains unknown, but it is believed to result from inflammation and swelling of the facial nerve, possibly due to a viral infection. The facial nerve passes through a narrow bony canal, and when it becomes inflamed, pressure builds up, interrupting the nerve’s ability to control facial muscles.
Possible causes and triggers include:
- Viral infections
- Herpes simplex virus (HSV-1) is most commonly linked to Bell’s palsy.
- Other viruses that may play a role include:
- Varicella zoster (causes chickenpox and shingles)
- Epstein-Barr virus (mononucleosis)
- Cytomegalovirus (CMV)
- Influenza and respiratory viruses
- HIV
- Immune response
- The body’s immune system may overreact to a viral infection, causing inflammation around the facial nerve.
- The body’s immune system may overreact to a viral infection, causing inflammation around the facial nerve.
- Reduced blood supply
- In some cases, restricted blood flow to the nerve may contribute to its dysfunction.
Risk factors include:
- Pregnancy, particularly in the third trimester or immediately after delivery
- Diabetes mellitus
- Upper respiratory tract infections
- High blood pressure
- Family history of Bell’s palsy
- Age: Most common between 15 and 60 years
- Stress and fatigue, which may suppress the immune system
In South Africa, viral illnesses such as cold sores, flu, and HIV-related infections may increase vulnerability to Bell’s palsy. The condition is not contagious, but those with weakened immunity may be more at risk.
Although Bell’s palsy can happen to anyone, recognising potential triggers and managing underlying health conditions like diabetes or hypertension may reduce the risk or aid in quicker recovery.
Causes and Risk Factors of Bell’s Palsy
Importantly, Bell’s palsy is different from a stroke — although both can cause facial weakness, strokes typically affect other parts of the body and involve slurred speech or limb weakness. A thorough medical assessment helps rule out other causes.
👉 [Next: Diagnosis of Bell’s Palsy]
