Table 2.
Evidence for acute analgesic treatments in trigeminal neuralgia. DN4, douleur neuropathique 4 questionnaire; GIC, global impression of change; IASP, International Association for the Study of Pain; ICHD, International Classification of Headache Disorders; IV, intravenous; MgSO4, magnesium sulphate; N, number of study patients; NRS, numerical rating scale; PE, phenytoin equivalents; PRS, pain relief scale; RCT, randomised controlled trial; SC, subcutaneous; TN, trigeminal neuralgia; V2, second division of trigeminal nerve; V3, third division of trigeminal nerve; VAS, visual analogue scale; VPR, verbal pain rating.
| Author (and year) | Drug | Study | Diagnosis | Population | N | Dosage | Route | Outcome measure(s) | Efficacy within 24 h | Side-effects (n) | Level of evidence | Risk of bias |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Zavon and Fichte17 (1991) | Proparacaine | Case report | Not specified | Classical TN Presenting for cataract surgery | 1 | 0.50% | Eye drops | Incidental reduction of TN pain | Alleviation of pain | Not specified | IV | High |
| Spaziante and colleagues16 (1992) | Proparacaine | Prospective observational | Not specified | Classical TN All divisions | 25 | 0.5% (2 drops) | Eye drops | 50% Reduction of analgesics | 15 Patients > 50% reduction (8 stopped all analgesics)—not clear at which timepoint over a 1 month period | Nil | IV | High |
| Kanai and colleagues19 (2006) | Lidocaine | RCT cross-over double-blind | ICHD | Classical TN Division: V2 Intensity on VAS>4/10 | 25 | Active: 8% 0.2 ml, Control: 0.2 ml saline | Nasal spray | VAS (15 min post-intervention), GIC (4-point scale), use of medications | Active: VAS 8.0 to 1.5, Control: 7.9 to 7.6, Duration: 4.3 h | Local irritation (stinging, burning numbness) (15), bitter taste or numb throat (1) | II | Unclear |
| Niki and colleagues20 (2014) | Lidocaine | RCT cross-over double-blind | ICHD | Classical TN Division: V2, V3 Intensity on VAS>4/10 | 24 | Active: 8% 0.2 ml, Control: saline 0.2 ml | Oral mucosa (trigger point)—applied via patients finger | NRS, GIC (4-point scale) | Active: NRS 5 to 1, Control: 5 no (change), Duration: 2.8 h | Numbness (active [9], control [3]), bitterness (1) | II | Unclear |
| Baykal and Kaplan24(2010) | Lidocaine | Retrospective observational | Not specified | Classical TN Division: V2, V3 | 13 | 5 ml 2% (100 mg) | ‘Blind’ injection of 2nd or 3rd division via mandibular notch | VAS | Complete relief 1–2 min post-injection | Hypoesthesia (4), dizziness (3), ptosis (1), insufficient block (1) | IV | High |
| Galer and colleagues21 (1993) | Lidocaine | Retrospective observational | Not specified | TN with concomitant persistent facial pain | 6 | 5 mg kg−1 h−1 | I.V. infusion over 60–90 min | VPR, VAS, PRS 1 h post-infusion | 5 Patients >70% reduction in VAS or VPR, 1 patient 30–70% reduction | Not specified | IV | High |
| Stavropoulou and colleagues23 (2014) | Lidocaine | RCT cross-over double-blind | IASP | Classical TN All divisions DN4 Score>4 VAS>3/10 | 20 | 5 mg kg−1 | I.V. infusion over 60 min | VAS, allodynia, hyperalgesia | VAS: (active) 76% reduction, (control) 40.1% reduction; at 24 h, (active) 52% reduction (control) 4% increase, decrease in evoked pain | Mild somnolence (33%), 3 patients dropped out | II | Low |
| Chaudhry and Friedman22 (2014) | Lidocaine | Case report | Not specified | TN with concomitant persistent facial pain Division: V2 |
1 | 60 mg h−1 for 4 h, 120mg h−1 for next 20 h, followed by 60 mg h−1 for next 48 h | I.V. infusion for 72 h | VPR | VPR: 10 to 0 after 1st h infusion | Not specified | IV | High |
| Arai and colleagues26 (2013) | Lidocaine+magnesium sulphate | Retrospective observational | Not specified | Classical TN Division: V2 | 9 | Lidocaine 100 mg and MgSO4 1.2 g | I.V. infusion over 60 min | NRS | NRS: 7 to 4 | Mild dizziness (2) | IV | High |
| Soleimanpour and colleagues25 (2014) | Magnesium sulphate | Case report | Not specified | Classical TN - acute presentation | 1 | 50 mg kg−1 | I.V. infusion over 30 min | VAS | VAS: 10 to 2 (30 min post-infusion) | Nil | IV | High |
| Tate and colleagues27 (2011) | Phenytoin | Case report | Not specified | Classical TN - acute presentation | 1 | 15 mg kg−1 | I.V. infusion in 2 divided doses 4 h apart | NRS | NRS: 10 to 2 after 1st infusion and 1 after 2nd infusion | Nil | IV | High |
| Cheshire29 (2001) | Fosphenytoin | Case series | Not specified | Classical TN - acute presentation, carbamazepine no longer effective | 3 | 14 (11–18) mg kg−1 (PE) over 20–180 min | I.V. infusion | Pain relief (not quantified) | Immediate pain relief post-infusion | Mild and transient dizziness, tinnitus, ataxia | IV | High |
| Vargas and Thomas28(2015) | Fosphenytoin | Case report | Not specified | Classical TN - acute presentation Division: V2+V3 | 1 | 15 mg kg−1 | I.V. infusion over 30 min | VAS | VAS: 10 to 2 | Not specified | IV | High |
| Zuniga and colleagues34 (2008) | Botulinum toxin | Prospective observational | Not specified | Classical TN All divisions | 12 | 20–50 units | S.C. trigger zones | VAS (8 weeks) | 10 Patients: relief ‘after some minutes’, 1 patient: VAS 10 to 0 in 24 h | Transient facial asymmetry (1) | IV | High |
| Kanai30 (2006) | Sumatriptan | RCT cross-over double-blind | ICHD | Classical TN All divisions Intensity on VAS>4/10 | 24 | Active: 3 mg (1 ml) Control: 1 ml saline |
S.C. | VAS (15 min post-intervention), GIC (4-point scale) | Active: Vas 8.3 to 2.4, Control: 8.5 to 8.1, Duration: 7.9 h | Mild hypertension (2), fatigue (5), nausea (2) | II | Unclear |
| Kanai32 (2006) | Sumatriptan | Prospective observational, placebo-controlled, partially blinded | ICHD | Classical TN All divisions | 15 | 3 mg (1 ml) s.c. followed by 50 mg orally twice daily for 1 week | S.C. saline, then s.c. sumatriptan, followed by oral 1 day later | VAS (15 min post-intervention) | VAS decreased by 4.0 (resting), 4.7 (touching face), 4.6 (talking) | Fatigue (4), nausea (2) | IV | High |
| Shimohata and colleagues33 (2009) | Sumatriptan | Case series | ICHD | Classical TN All divisions |
3 | 20 mg | Nasal spray | VAS | VAS: 8 to 2 (30 min) | Nil | IV | High |