Crocodile Tears Syndrome, medically known as gustatory lacrimation or Bogorad syndrome, is a condition where individuals involuntarily produce tears while eating or drinking. The colloquial name originates from an ancient myth that crocodiles weep while consuming their prey, a metaphor for the syndrome’s primary symptom.
The Neurological Cause
This syndrome arises from aberrant nerve regeneration following an injury to the facial nerve, also known as cranial nerve VII. The facial nerve is responsible for various functions, including controlling facial expressions, salivation, and tear production. After damage, nerve fibers that were originally meant to stimulate the salivary glands mistakenly regrow and connect to the lacrimal gland, which produces tears.
This misdirection of nerve impulses creates a “crossed wires” effect. When a person eats, the brain sends signals to produce saliva, but due to the miswired connections, these signals also incorrectly stimulate the lacrimal gland. This results in the unexpected and involuntary shedding of tears during meals, typically affecting one eye.
Diagnosis and Associated Conditions
Diagnosis of Crocodile Tears Syndrome typically relies on a patient’s medical history and a description of symptoms. Doctors often confirm the condition by observing the patient tearing while stimulating salivation, for instance, by offering a lemon drop. This helps differentiate it from other causes of watery eyes, such as blocked tear ducts or infections.
The most common underlying cause of facial nerve damage leading to this syndrome is Bell’s palsy, a temporary facial paralysis. Crocodile Tears Syndrome occurs in approximately 3.3% of Bell’s palsy cases, usually developing about 6 to 9 months into recovery. Other potential causes of facial nerve injury include surgical complications, head trauma, or certain infections like herpes zoster oticus.
Available Treatment Options
The most common and effective treatment for Crocodile Tears Syndrome involves injections of botulinum toxin, often referred to as Botox, directly into the affected lacrimal gland. This neurotoxin works by blocking the faulty nerve signals, preventing misdirected salivary nerve fibers from stimulating tear production.
Botulinum toxin injections offer a temporary solution, with effects typically lasting between 4 to 6 months. Patients generally experience a significant reduction or complete disappearance of tearing during meals following treatment. Since the effects are not permanent, repeat injections are usually necessary to maintain symptom control.
While botulinum toxin is the standard, other less common treatments exist, such as certain medications or surgical procedures like vidian neurectomy. These are often reserved for severe or unresponsive cases. Botulinum toxin injections are widely favored due to their effectiveness and a generally favorable safety profile, though minor and temporary side effects like eyelid drooping or dry eye can occur.