Bell's palsy: what it is and why it belongs in the history
Quick facts
- Definition
- Sudden peripheral facial paralysis on one side, with no identified cause.
- Onset
- Over hours to a few days, with weakness affecting the forehead, eye and mouth on the same side.
- Course
- In many cases it improves over weeks to months, but recovery varies.
- Importance in HOF
- A history or active episode calls for medical assessment and caution with toxin.
Bell's palsy is a peripheral facial paralysis of sudden onset, usually on one side only, with no identified cause. It affects the facial nerve and makes the forehead, eye and mouth on the affected side lose strength. It is the most common form of facial paralysis of undetermined cause, and the diagnosis is one of exclusion.
How does Bell's palsy show up?
The patient often wakes up with one side of the face "drooping", difficulty closing the eye, a crooked mouth and a feeling of heaviness. There may be pain behind the ear, altered taste and sensitivity to sound. Because it is peripheral, it affects the entire side, including the forehead, which sets it apart from central causes.
| Sign | In peripheral paralysis (such as Bell's palsy) |
|---|---|
| Forehead | Does not wrinkle on the affected side |
| Eye | Does not close completely |
| Mouth | Pulls toward the healthy side |
| Onset | Sudden |
If incomplete eye closure persists, the cornea is at risk (lagophthalmos), and ophthalmologic follow-up becomes part of the care.
Why does Bell's palsy belong in the HOF medical history?
The HOF professional often sees patients who have had an episode and are now "recovered" with mild sequelae. This has practical consequences.
- Botulinum toxin: it reduces contraction of the treated muscles. In someone with residual weakness or synkinesis (associated movements), the result may differ from what is expected and the asymmetry may be more marked. Treatment needs a frank conversation, detailed consent and, often, an opinion from the physician following the patient. See botulinum toxin.
- Patient with an active episode: no elective procedure is performed on a face with acute paralysis without medical assessment.
- Asymmetry: the patient may blame the toxin for an asymmetry that was already there. Photography and a record of the exam before treating protect both sides. See facial asymmetry.
What should be recorded in the assessment?
Also known as: idiopathic facial paralysis, Bell's palsy.
Frequently asked questions
Can I inject toxin in someone who has had Bell's palsy?
It depends on the assessment. A history calls for caution, a frank conversation about sequelae and asymmetries and, often, an opinion from a physician. The decision belongs to the qualified professional.
Is Bell's palsy the same as a stroke?
No. Bell's palsy is peripheral and affects the whole side of the face, including the forehead. In a stroke, the forehead is usually spared. Any doubt is a medical emergency.