Do COVID Vaccines Cause Bell’s Palsy? A Look at the Evidence
- Dr. Alexandra LaStella, PharmD, RPh
- Sep 21
- 3 min read
✎ Dr. Alexandra LaStella, Pharm.D, RPh
doi: 10.70390/75sdfxt9
Bell’s palsy (BP) is a sudden, temporary weakness or paralysis of one side of the face, often linked to viral infections that inflame the facial nerve. When COVID-19 vaccines first became available, reports of Bell’s palsy among trial participants sparked public concern. Was there a real risk, or just coincidence? Four years later, the most recent evidence allows us to separate fact from fear.
Neurological Effects of COVID-19
Since the start of the pandemic, scientists have documented a range of neurological effects related to both COVID-19 infection and vaccination. These include conditions such as stroke, Guillain–Barré syndrome, encephalitis, and Bell’s palsy.[1]
Several biological mechanisms have been proposed to explain how either infection or vaccination might affect the nervous system. Immune overactivation can drive inflammation within the central nervous system. Molecular mimicry occurs when viral proteins share structural similarities with human proteins, potentially causing antibodies to mistakenly target nerve tissue. Other hypotheses include cytokine surges and temporary disruption of the blood–brain barrier, which could make it easier for immune cells to irritate the nervous system.
Bell’s palsy, in particular, has drawn attention because of its sudden onset and visible symptoms. While the exact causes remain unclear, viral infections such as herpes simplex virus (HSV) and varicella zoster virus (the virus that causes chickenpox and shingles) are well-established triggers. Given its viral triggers and sudden onset, Bell’s palsy quickly drew attention as researchers monitored both COVID-19 infections and vaccinations.
Bell’s Palsy After Infection: Higher Risk and Worse Outcomes
meta-analysis found a significantly higher rate of facial nerve palsy during the pandemic, largely driven by infection rather than vaccination.[2] Recovery outcomes were also worse: about 57% of patients with COVID-related Bell’s palsy recovered fully, compared to roughly 83% in typical, idiopathic Bell’s palsy.
Another systematic review of 73 patients provided additional detail: Non-GBS cases (not associated with Guillain–Barré syndrome) were younger, mostly unilateral, and recovered more quickly—about two-thirds regained full function within a few weeks.[3] GBS-associated cases were older, often bilateral, and had poorer outcomes, with only 13–17% achieving complete recovery.
These findings suggest that COVID-19 infection can trigger atypical forms of facial paralysis, sometimes more severe and less responsive to standard treatment than classic Bell’s palsy.
Bottom Line for Patients and Providers
The available evidence consistently shows no increased risk of Bell’s palsy after COVID-19 vaccination, while the infection itself carries both a higher risk of facial paralysis and worse outcomes.
For patients who worry about facial paralysis as a vaccine side effect, the science is reassuring: vaccination is the safer path. For healthcare providers, these findings reinforce the importance of clear communication: acknowledging concerns, but emphasizing the stronger and more harmful link between Bell’s palsy and COVID-19 infection.
Ongoing surveillance remains essential, but the weight of data points in one direction: the benefits of vaccination far outweigh the risks.
References
1. Algahtani H, Shirah B, Mustafa A, et al. COVID-19 vaccines and neurological disorders: A narrative review of immune responses and adverse reactions. AIMS Neurosci. 2025;12(2):237-256. doi:10.3934/Neuroscience.2025012
2. Patel V, Gadhvi K, Ng J, et al. Facial nerve palsy amid the SARS-CoV-2 pandemic: A pooled analysis. J Otolaryngol Head Neck Surg. 2025;54(1):15. doi:10.1186/s40463-025-00712-5
3. Namavarian A, Eid A, Ziai H, Cheng EY, Enepekides D. Facial nerve paralysis and COVID-19: A systematic review. Laryngoscope. 2022;132(12):2335-2347. doi:10.1002/lary.30333
Appendix
Patient Information: Bell's Palsy
This printable handout is provided to support patient counseling and education on Bell’s palsy.
Source: American Academy of Family Physicians [AAFP])
