The First 72 Hours of Bell's Palsy

Bell's palsy typically reaches full severity within 48 to 72 hours, and what happens in that short window often shapes the diagnosis and treatment path that follows. A drooping eyebrow, a mouth that will not move evenly, an eye that cannot fully close: these changes can arrive within hours and leave patients searching for answers immediately. Dr. Tessa Hadlock, M.D., a Harvard Medical School professor and former director of the Facial Nerve Center at Massachusetts Eye and Ear, has spent over three decades studying facial nerve disorders. That early window is one she returns to often with patients newly facing this diagnosis.

This blog explores what happens in the first 72 hours of Bell's palsy, why timing matters, and what steps can support the best possible recovery.

What Happens to the Face During This Window

One side of the face loses function suddenly, often noticed first thing in the morning when a smile will not form evenly or an eyelid refuses to close. The forehead, cheek, and lip muscles can all weaken together, and some patients also notice a change in taste, sensitivity to loud sound, or a dull ache near the ear. These symptoms tend to intensify quickly, then plateau. The exact trigger is not fully understood, though most evidence points to a herpes simplex virus that lies dormant in the cranial nerves and reactivates under stress, illness, or immune suppression.

Why the First 72 Hours Matter for Diagnosis

According to the National Institute of Neurological Disorders and Stroke, Bell's palsy symptoms characteristically peak within a 48 to 72 hour span before beginning to stabilize. Dr. Hadlock and her colleagues rely on this pattern to distinguish Bell's palsy from other causes of facial weakness. Facial weakness that does not begin to improve within four months points toward a different underlying condition, and further testing is usually needed.

What to Do in the First 72 Hours

A few prompt steps can support comfort and recovery in this early window:

• Seek a medical evaluation as soon as weakness appears, since timing can affect treatment options
• Protect the affected eye with daytime lubricating drops and a thicker nighttime ointment or gel
• Tape the eye closed during sleep if it does not close on its own, to guard against corneal irritation
• Track how symptoms change hour to hour, which helps a clinician confirm the diagnosis
• Avoid assuming the cause without an exam, since stroke and other conditions can mimic early Bell's palsy

Early Treatment Considerations

Oral steroids, started within three days of onset, may help reduce nerve inflammation and support a fuller recovery. Antiviral medications such as valacyclovir are sometimes added alongside steroids, though their individual benefit remains a point of ongoing discussion among clinicians. Facial nerve decompression surgery, which relieves pressure on the nerve, is occasionally considered in select cases, though its role continues to be studied. Most patients recover well with medication and eye care alone.

Roughly 70 percent of people with Bell's palsy go on to recover full facial function. For the remaining patients, some tightness or involuntary movement can persist, a pattern known as synkinesis. When that happens, facial nerve physical therapy, BOTOX injections, or surgical intervention can help restore balance and control over time.

Dr. Tessa Hadlock, M.D.: Guidance From the First Hour Onward

Those first 72 hours can feel disorienting. They are also the window where informed decisions make the biggest difference. Dr. Hadlock's three decades of research and clinical experience in facial nerve disorders give patients a steady, evidence-based path forward from the moment symptoms appear. Anyone noticing sudden facial weakness should contact the Hadlock Center for Facial Plastic Surgery to schedule a consultation and begin care without delay.

This information is provided for educational purposes only and does not replace a consultation with a board-certified facial plastic surgeon. Outcomes, risks, and suitability vary from patient to patient.