What is the workup for a patient presenting with trigeminal neuralgia (shooting pain in the face)?

From the Guidelines

A shooting pain in the face should be evaluated with a thorough neurological examination focusing on cranial nerves, particularly the trigeminal nerve (CN V), and initial management should include a trial of carbamazepine, as it is the most effective treatment for trigeminal neuralgia, with a significant reduction in pain intensity, as shown in a systematic review 1. The workup should begin with a detailed history of the pain characteristics, including:

• Timing: onset, duration, and periodicity
• Location and radiation (e.g. within nerve distribution)
• Quality and severity
• Relieving and aggravating factors (e.g. effect of hot, cold sweet foods, prolonged chewing, eating, brushing of teeth, touching the face, weather, physical activity, posture, stress, and tiredness) 1. Physical examination should assess facial sensation, corneal reflexes, and jaw movements. Initial diagnostic testing typically includes brain MRI with contrast to evaluate for structural causes like tumors, vascular compression, or demyelinating lesions. Additional tests may include trigeminal reflex testing, MR angiography to assess vascular structures, and laboratory studies to rule out systemic conditions like autoimmune disorders or infections. If trigeminal neuralgia is suspected, a trial of carbamazepine (starting at 200mg at night and gradually increased by 200mg every 7 days to a final dose of 400–1200mg, divided in 2–3 doses per day) is both diagnostic and therapeutic, with 70% of patients showing partial or complete pain relief 1. For atypical facial pain, other medications like gabapentin (300-1200mg three times daily) or amitriptyline (10-75mg at bedtime) may be considered. Patients should be referred to a neurologist or pain specialist if symptoms persist despite initial management, as interventional procedures like microvascular decompression or stereotactic radiosurgery might be necessary for refractory cases, with microvascular decompression providing the best rates of long-term complete pain relief and preservation of facial sensation 1. The workup is essential because facial pain can result from various conditions ranging from benign trigeminal neuralgia to serious pathologies like multiple sclerosis or intracranial masses. It is crucial to note that the management of trigeminal neuralgia should prioritize the patient's quality of life, and treatment decisions should be made based on the most recent and highest-quality evidence available, with carbamazepine being the primary drug of choice, as suggested by international guidelines and Cochrane reviews 1.

From the FDA Drug Label

Carbamazepine tablets are indicated in the treatment of the pain associated with true trigeminal neuralgia. The FDA drug label does not provide a specific workup for shooting pain in the face, but it does indicate that carbamazepine is used to treat trigeminal neuralgia, which is characterized by shooting pain in the face.

• Key points:
  • Trigeminal neuralgia is a condition that causes shooting pain in the face.
  • Carbamazepine is indicated for the treatment of trigeminal neuralgia.
  • No specific workup is provided in the FDA drug label for shooting pain in the face. 2

From the Research

Shooting Pain in Face Work Up

• The work up for shooting pain in the face involves a comprehensive approach, considering various etiologies and disciplines, as highlighted in 3.
• A key aspect of the work up is to exclude life- or organ-threatening diseases, and to provide clinical clues and indications for technical investigations, as noted in 3.
• Trigeminal neuralgia is a common form of craniofacial pain that can cause sudden, brief, and excruciating facial pain attacks, and its diagnosis and treatment should be considered in the work up, as discussed in 4 and 5.

Diagnostic Considerations

• A structured history of the pain and its associated symptoms is essential in the work up, as emphasized in 6.
• Nasendoscopy and relevant targeted investigations should be performed to lead to a correct diagnosis and appropriate treatment, as suggested in 6.
• Imaging, such as CT scans, should not be routinely performed for facial pain, due to the prevalence of incidental changes in asymptomatic patients, as noted in 6.

Treatment Options

• The treatment of trigeminal neuralgia typically involves antiepileptic drugs, such as carbamazepine and oxcarbazepine, as first-line options, as discussed in 4 and 5.
• Other treatment options, including interventional or surgical procedures, may be necessary for patients resistant to or intolerant of drug therapy, as noted in 5.
• Behavioral strategies and preventive treatment are also important aspects of headache management, as highlighted in 7.