Trigeminal Neuralgia Crisis – Intravenous Phenytoin as Acute Rescue Treatment

Abstract

Objective The aim of this retrospective cohort study was to analyze responses to intravenous (IV) phenytoin (PHT) for trigeminal neuralgia (TN) crisis in a group of patients treated at our institution. Background TN is one of the most common causes of facial pain. Its treatment relies on preventive therapy with either carbamazepine or oxcarbazepine. During severe pain episodes, patients may be unable to eat, drink, or even swallow oral medication, requiring in‐hospital treatment. There is scarce evidence to support IV medication use for TN, making management of this condition difficult. Methods We reviewed clinical records of patients with TN crisis consulting the emergency department at a tertiary neurological referral center in Buenos Aires, Argentina, treated with IV PHT as analgesic strategy, and with at least 1‐month posttreatment follow‐up. Demographic features, magnetic resonance imaging findings, and therapeutic management were analyzed. Results Thirty‐nine patients with TN were included, 18 (46.2%) receiving IV PHT more than once (total number of infusions administered, 65). Immediate pain relief was observed in 89.2% (58/65) and 15.4% (10/65) presented side effects. Conclusions We recommend IV PHT as acute rescue treatment in TN crisis.

The Molecular Basis and Pathophysiology of Trigeminal Neuralgia

“…An intranasal spray of 8% lidocaine has also shown statistically significant pain reduction for four hours in patients with second-division TN [ 118 ]. Intravenous phenytoin, yet another Nav blocker, demonstrated an acute response rate of 89% in a retrospective cohort, including classic, idiopathic, and secondary TN [ 119 ]. Fosphenytoin, a prodrug of phenytoin, has similarly shown positive results in aborting TN exacerbations in small case reports [ 120 , 121 ].…”

Scalp dysesthesia: a neuropathic phenomenon

“…Targeted nerve blocks have been effective in a case report for intractable post‐herpetic itch 62 . IV phenytoin provides rapid relief of neuropathic dysesthesias and has been used as an acute rescue treatment for trigeminal neuralgias 63 …”

“…62 IV phenytoin provides rapid relief of neuropathic dysesthesias and has been used as an acute rescue treatment for trigeminal neuralgias. 63 In instances where self-induced ulcerations are present at the site of pruritus, which is common in TTS, patient education and counseling is necessary to prevent and reverse repetitive manipulation of the injured tissue. 23 Cognitive behavioral therapy such as habit reversal training and relaxation training may be used to control the itch-scratch cycle and improve quality of life.…”

Virtual issue: Cranial neuralgias

“…Crespi et al examine sphenopalatine ganglion onabotulinumtoxinA injections, and while they did not meet their primary efficacy endpoint (reduced number of attacks at weeks 5–8, compared to baseline), four of 10 patients experienced >50% reduction in median attacks per day 10 . Schnell et al describe the use of IV phenytoin for trigeminal neuralgia crises, adding to the literature on this often difficult‐to‐treat presentation 11 . Lastly, Kern et al report a small series of trigeminal neuralgia patients who responded to topical ambroxol 20%, an expectorant with local anesthetic properties considered approximately 40 times stronger than lidocaine 12 .…”