In a geriatric patient scheduled for total knee arthroplasty, is it appropriate to taper gabapentin by 25–50% every 3–5 days?

Gabapentin Tapering Before Total Knee Arthroplasty in Geriatric Patients

Yes, tapering gabapentin by 25–50% every 3–5 days is appropriate and aligns with FDA labeling, which states that gabapentin should be discontinued "gradually over a minimum of 1 week" when reduced or substituted. 1 However, for geriatric patients on chronic therapy, a more conservative approach may be warranted.

Evidence Against Perioperative Gabapentin Use

The rationale for discontinuing gabapentin before total knee arthroplasty is supported by recent high-quality evidence:

• The 2022 AAOS/METRC guideline found no significant difference in pain alleviation or opioid consumption with gabapentin in total hip and knee arthroplasty patients, whether given as a single preoperative dose or multidose regimen. 2

• The 2021 British Journal of Anaesthesia expert consensus specifically cautions that "before gabapentinoids are used in older adults, the benefits vs potential risk should be considered," noting increased incidence of dizziness and visual disturbance with no clinically significant impact on postoperative pain. 2

• Multiple randomized controlled trials confirm this lack of benefit: a 2022 study of gabapentin enacarbil showed no significant differences in pain scores or opioid consumption 3, and a 2013 trial found no effect on morphine consumption, pain scores, or patient satisfaction. 4

Recommended Tapering Protocol

Standard Approach (FDA-Compliant)

For patients on gabapentin ≤900 mg/day:

• Reduce by 25–50% every 3–5 days over a minimum of 1 week 1
• Example: 900 mg/day → 600 mg/day (days 1–3) → 300 mg/day (days 4–6) → discontinue (day 7)

For patients on higher doses (>900 mg/day) or chronic use (>6 months):

• Use a more conservative 25% reduction every 3–5 days 5
• Extend taper to 2–4 weeks for elderly patients on lower doses 5

Geriatric-Specific Considerations

Mandatory renal function assessment is required before tapering, as elderly patients frequently have decreased creatinine clearance. 1 Calculate creatinine clearance using the Cockcroft-Gault equation and adjust the tapering schedule accordingly. 1

Elderly females are at particularly high risk for falls during withdrawal due to dizziness, confusion, and akathisia. 5 Monitor closely for these symptoms and slow the taper if they emerge.

Polypharmacy concerns are paramount in geriatric patients, as multiple CNS-active medications may complicate withdrawal. 5 Review all concurrent medications, particularly opioids, benzodiazepines, and other sedating agents. 2

Timing Relative to Surgery

Ideally, complete the gabapentin taper 1–2 weeks before surgery to allow clearance and minimize perioperative confusion or dizziness. 2 This timing also avoids the scenario where gabapentin is restarted postoperatively despite lack of efficacy data.

If surgery is scheduled within 2 weeks and the patient is on a stable, low dose (≤300 mg/day), consider simply discontinuing gabapentin 7 days preoperatively per FDA minimum guidance. 1

Monitoring During Taper

Assess for withdrawal symptoms at each dose reduction:

• Anxiety, agitation, or mood changes
• Insomnia or sleep disturbance
• Tremor or muscle aches
• Dizziness or gait instability (especially critical in elderly patients) 5

If withdrawal symptoms emerge, pause the taper at the current dose for 3–5 days before proceeding. This is consistent with the FDA's discretionary language allowing "a longer period" at prescriber discretion. 1

Common Pitfalls to Avoid

Do not abruptly discontinue gabapentin, even at low doses, as the FDA explicitly requires gradual reduction. 1 While gabapentin withdrawal is not life-threatening like benzodiazepine withdrawal, abrupt cessation can cause significant discomfort and anxiety.

Do not assume gabapentin provides meaningful postoperative analgesia in this population. The evidence is clear that it does not reduce pain or opioid consumption after total knee arthroplasty. 2, 3, 4

Avoid restarting gabapentin postoperatively "for pain control" without a specific neuropathic indication. The 2021 perioperative brain health consensus emphasizes that gabapentinoids in older adults carry risks (dizziness, visual disturbance) without demonstrated benefit. 2

Alternative Multimodal Analgesia

Instead of gabapentin, prioritize evidence-based analgesics for total knee arthroplasty:

• COX-2 selective NSAIDs have strong evidence for limiting opioid use and improving function. 2
• Acetaminophen (scheduled dosing) should be used to improve pain and decrease opioid consumption. 2
• Intravenous ketamine in the perioperative period has strong evidence for decreased opioid use in the first 24 hours. 2
• Local anesthetic blocks and infiltration are recommended components of multimodal pain management. 2

Adequate postoperative analgesia is associated with delirium reduction in older adults, making multimodal pain management critical—but gabapentin is not part of the evidence-based regimen. 2

Summary Algorithm

1. Assess renal function using Cockcroft-Gault equation 1
2. If dose ≤900 mg/day: Reduce by 25–50% every 3–5 days over 1–2 weeks 1, 5
3. If dose >900 mg/day or chronic use: Reduce by 25% every 3–5 days over 2–4 weeks 5
4. Monitor for withdrawal symptoms (dizziness, anxiety, insomnia) at each reduction 5
5. Pause taper if symptoms emerge; resume when stable 1
6. Complete taper 1–2 weeks before surgery to allow clearance 2
7. Do not restart gabapentin postoperatively unless specific neuropathic indication exists 2