Single-dose botulinum toxin type a compared with repeated-dose for treatment of trigeminal neuralgia: a pilot study

Abstract

BackgroundSeveral RCT studies including ours, seem to prove the role of Botulinum toxin type A (BTX-A) in the treatment of trigeminal neuralgia (TN), but no standardized dosing regimen has been established. In our study, we compare two different methods of administration: single-dose or repeated-dose strategy which was most frequently applied over the years in our centre.MethodsAn open-label trail was conducted. One hundred patients with classic TN symptoms were recruited, and randomly and equally apportioned to single- or repeated-dose group. Patients in the single-dose group received a local BTX-A injection of 70 to 100 U. The repeated-dose group received an initial BTX-A injection of 50 to 70 U and then another of equal volume 2 weeks later. All patients were followed for 6 months.ResultsIn the single- and repeated-dose groups, 44 and 37, respectively, completed the entire study. The groups were statistically similar in TN frequency, time between treatment and effect, time to peak effect, VAS scores, and rates of adverse reactions (latency and duration). However, the single-dose group experienced significantly longer duration of effect (P = 0.032).ConclusionsThe single- and repeated-dosing BTX-A regimens were largely comparable in efficacy and safety. This study suggests that repeated dosing has no advantage over single dosing of BTX-A for TN. Dosing should be adjusted for the individual patient.

Use of Botulinum Toxin in Orofacial Clinical Practice

“…The groups were statistically similar in frequency, maximum time, VAS scores and adverse reaction rates. However, the effect duration increased significantly in the single-dose group [38].…”

Botulinum Neurotoxin for the Treatment of Neuropathic Pain

“…Negative results emerged in two RCTs, (one in PSP and one in CTS) ( 69 , 73 ) while one RCT in CRPS was stopped due to low tolerability ( 84 ). The positive effects of BoNT/A on NP started after 4–8 weeks [after 1 week in TN ( 34 , 35 , 39 )] and persisted up to 6 months after treatment ( 34 , 37 – 42 , 45 , 60 , 62 , 68 , 70 , 71 , 89 , 90 , 94 ). The duration of BoNT/A benefit was dependent on toxin dose, injection site, number and depth of injections in NP ( 40 , 41 ) but not in TN ( 34 , 37 – 42 , 45 ).…”

“…One major limitation is the use of different toxin serotypes and preparations which hampers the comparison of studies' results. Most studies specified the use of the common BoNT/A brand (Botox®) ( 27 , 29 , 32 , 34 , 36 , 40 , 43 , 44 , 52 , 55 , 67 – 71 , 74 , 77 , 84 , 89 , 90 , 93 , 101 ) or other BoNT/A compounds (e.g., HengLi®, Meditoxin®, Disport®) ( 33 , 38 , 39 , 41 , 50 , 62 , 72 , 94 , 96 ), but, in many cases, no specification of the BoNT/A serotype was provided ( 27 , 31 , 35 , 37 , 42 , 47 , 51 , 53 , 54 , 60 , 61 , 66 , 75 , 78 , 83 , 85 , 86 , 94 , 102 – 104 ). Furthermore, two studies were performed with botulinum toxin type B ( 73 , 87 ) and two with incobotulinum toxin type A ( 76 , 88 ).…”

<p>Botulinum Toxin Type A for refractory trigeminal neuralgia in older patients: a better therapeutic effect</p>

“…We have since established a clinical database. Through several clinical trials, our group have investigated the effects,17 safety,17 dosage,18 treatment schedule19 and long-term efficacy20 of BTX-A for treating TN. However, BTX-A treatment is still ineffective for approximately 10–43% of patients 17–20.…”