What is the treatment plan for an 80-year-old female with new onset intermittent sharp shooting temporal pain, suggestive of trigeminal neuralgia, that radiates to the rest of her face and mouth?

From the Guidelines

For an 80-year-old female with suspected trigeminal neuralgia, I recommend starting with carbamazepine (Tegretol) at 100mg twice daily, gradually increasing by 100mg every 3-5 days as needed until pain relief is achieved or side effects occur, typically up to 200-400mg twice daily, as supported by the highest quality evidence from 1 and 1.

Treatment Plan

The treatment plan should prioritize carbamazepine as the first-line agent due to its efficacy in reducing pain in trigeminal neuralgia, with 70% of patients showing partial or complete pain relief 1.

• Monitor for side effects including dizziness, drowsiness, and hyponatremia, with baseline and follow-up complete blood counts and liver function tests.
• If carbamazepine is not tolerated, oxcarbazepine (Trileptal) starting at 150mg twice daily and titrating up to 600mg twice daily is a good alternative with fewer drug interactions, as suggested by 1.

Alternative Options

For patients who fail these medications,

• gabapentin (300mg daily, increasing to 300-600mg three times daily) or
• pregabalin (75mg twice daily, increasing to 150-300mg twice daily) can be tried.
• Baclofen (5mg three times daily, increasing to 20mg three times daily) may be added for additional relief.

Surgical Intervention

If medical management fails after 3-6 months, refer for neurosurgical evaluation for procedures like microvascular decompression or stereotactic radiosurgery, considering the potential benefits and risks as outlined in 1.

Mechanism of Action

Carbamazepine works by blocking sodium channels, reducing the hyperexcitability of trigeminal nerve fibers that causes the characteristic paroxysmal pain in trigeminal neuralgia, as explained in 1.

From the FDA Drug Label

Carbamazepine tablets are indicated in the treatment of the pain associated with true trigeminal neuralgia. Beneficial results have also been reported in glossopharyngeal neuralgia. This drug is not a simple analgesic and should not be used for the relief of trivial aches or pains.

The patient's symptoms of new onset intermittent sharpshooting temporal pain that radiates to the rest of her face and mouth are consistent with trigeminal neuralgia.

• Carbamazepine (PO) is indicated for the treatment of this condition 2.
• It is not a simple analgesic and should only be used for true trigeminal neuralgia, not for trivial aches or pains.
• Given the patient's symptoms, carbamazepine (PO) may be considered as a treatment option.

From the Research

Treatment Plan for Trigeminal Neuralgia

The treatment plan for trigeminal neuralgia typically involves medical management as the initial approach, with carbamazepine being the drug of choice 3, 4. If the patient proves to be intolerant of carbamazepine, other options such as oxcarbazepine, phenytoin, baclofen, clonazepam, and sodium valproate can be considered 3.

Medical Management

• Carbamazepine is the first-line treatment for trigeminal neuralgia, with a mechanism of action that modulates voltage-gated sodium channels, leading to a decrease in neuronal activity 4.
• Oxcarbazepine is also a first-line treatment option, with a similar mechanism of action to carbamazepine 4.
• Other medications that may be useful for pain control in trigeminal neuralgia include gabapentin, pregabalin, lamotrigine, and phenytoin 4.

Surgical Intervention

• For patients who are resistant to or intolerant of drug therapy, interventional or surgical procedures may be necessary 3.
• Microvascular decompression is recommended for younger, fit patients, particularly with involvement of the first division or all three divisions of the nerve 3.
• Radiofrequency thermal rhizotomy is probably the next treatment of choice for older patients or those not willing to undergo craniectomy 3.
• Other techniques to be considered include glycerol rhizotomy, balloon compression, partial sensory trigeminal rhizotomy, and peripheral neurectomy 3.

Effectiveness and Tolerability

• Carbamazepine and oxcarbazepine are highly effective in the long-term treatment of trigeminal neuralgia, with an initial proportion of responders of 88.3% and 90.9%, respectively 5.
• However, side effects are still a major issue, particularly in patients with secondary and idiopathic trigeminal neuralgia, with frequencies of side effects associated with carbamazepine and oxcarbazepine being 43.6% and 30.3%, respectively 5.

Considerations for the 80-Year-Old Female Patient

• Given the patient's age, radiofrequency thermal rhizotomy or other less invasive surgical procedures may be considered if medical management is not effective or tolerated 3.
• The choice of treatment should be individualized, taking into account the patient's overall health, medical history, and preferences 3, 6.