Is there a role for pregabalin (an anticonvulsant medication) in treating cervical radiculopathy with a significant neuropathic pain component?

Role of Pregabalin in Cervical Radiculopathy with Neuropathic Pain

Pregabalin is recommended as a reasonable treatment option for cervical radiculopathy with significant neuropathic pain component, with a recommended dosage of 75 mg twice daily initially, titrated up to 300-600 mg/day based on response and tolerability. 1

Mechanism and Efficacy

Pregabalin is an antiepileptic medication that binds to the α2-δ subunit of voltage-sensitive calcium channels, which helps reduce the release of excitatory neurotransmitters involved in pain signaling 2. Its efficacy in neuropathic pain conditions is well-established, particularly for:

• Diabetic peripheral neuropathy
• Postherpetic neuralgia
• Fibromyalgia

While cervical radiculopathy is not specifically listed in the FDA-approved indications, evidence supports its use in neuropathic pain conditions with similar pathophysiology 1. The medication shows efficacy within the first several days of administration 2.

Dosing Recommendations

For neuropathic pain management in cervical radiculopathy:

• Initial dose: 75 mg twice daily or 50 mg three times daily
• Titration: Increase gradually based on response and tolerability
• Target dose: 300-600 mg/day in divided doses
• Maximum dose: 600 mg/day 1

Pregabalin has superior pharmacokinetic properties compared to gabapentin:

• Higher bioavailability (>90%, dose-independent)
• Faster titration (days vs weeks)
• Lower therapeutic dose (150-600 mg/day vs 900-3600 mg/day)
• Quicker time to steady state (24-48 hours) 1

Evidence in Radiculopathy

A 2018 study demonstrated that pregabalin at 75 mg daily significantly reduced pain intensity in patients with subacute and chronic cervical and lumbosacral radiculopathy as measured by visual analog scale (VAS) and numerical pain scales 3. The study showed approximately 47% reduction in pain severity and improved daily function.

Another study from 2019 showed that pregabalin effectively treated neuropathic pain in patients with chronic low back pain associated with radiculopathy 4. This study noted significant improvement in DN4 neuropathic pain scores at both 4 and 12 weeks of treatment.

Adverse Effects and Monitoring

Common adverse effects include:

• Dizziness (27-46% at 600 mg/day)
• Somnolence (15-25% at 600 mg/day)
• Weight gain
• Peripheral edema (especially in elderly patients) 1

Important monitoring considerations:

1. Balance and gait may be affected initially but tolerance typically develops with continued use 4
2. Neuropsychological reactions may occur, particularly in elderly patients 1
3. No significant drug interactions due to lack of hepatic metabolism and no interaction with cytochrome P-450 isoenzymes 5

Dose Optimization

Higher doses of pregabalin have demonstrated greater efficacy in neuropathic pain management. A pooled analysis of flexible-dose trials showed that many patients who do not respond to lower doses (150 mg/day) will experience notable improvements when the dose is escalated to 300-600 mg/day 6. Therefore, it's important to titrate to an effective dose rather than abandoning treatment prematurely.

Clinical Approach

For patients with cervical radiculopathy with significant neuropathic pain:

1. Start with pregabalin 75 mg twice daily
2. Assess response after 1-2 weeks
3. If inadequate response but tolerable side effects, increase to 150 mg twice daily
4. Continue titration up to 300 mg twice daily as needed and tolerated
5. Monitor for adverse effects, particularly dizziness and somnolence
6. Assess for improvement in neuropathic pain symptoms using validated tools

Cautions and Contraindications

• Renal impairment requires dose adjustment
• Pregabalin is a Schedule V controlled substance due to potential for abuse and dependence 5
• Not recommended for acute pain management, including postoperative pain 1
• Use with caution in elderly patients due to higher rates of adverse events 1

Pregabalin represents a valuable option for managing the neuropathic pain component of cervical radiculopathy, with evidence supporting its efficacy and a manageable side effect profile when properly titrated.