Efficacy and Safety Study of Lamotrigine to Treat Trigeminal Neuralgia

Trigeminal Neuralgia Clinical Trial

Official title: Lamotrigine in Trigeminal Neuralgia: Efficacy and Safety in Comparison With Carbamazepine

Status Completed

Clinical Trial Summary

The purpose of this study was to determine the efficacy and safety of lamotrigine in patients with trigeminal neuralgia (TGN).

Clinical Trial Description

Trigeminal Neuralgia (TGN) is a rare form of chronic facial pain shrouded in mystery, although not life threatening, can be excruciating painful and extraordinarily debilitating. Its uniqueness and peculiarity can be ascertained by the fact that TGN may present to and be managed by dentists, neurologists, neurosurgeons, oral surgeons and ear, nose and throat surgeons.

The management of TGN is initially medical, with the "gold standard" drug of carbamazepine (CBZ). Whilst CBZ continues to be the treatment of choice, a substantial proportion of patients tolerate this drug poorly, predominantly because of side-effects that include drowsiness, accommodation disorders, hepatitis, elevation in liver enzymes, renal dysfunction, congestive heart failure, delayed multi-organ failure, leucopenia, thrombocytopenia etc. etc. If pain-relief is incomplete with CBZ or it produces adverse side-effects, options include using an alternative second-line medical agent. The drugs suggested to be considered as second-line agents for the treatment of TGN, include: lamotrigine, baclofen, phenytoin, oxcarbazepine, gabapentin, clonazepam, valproate, mexiletine, and topiramate.

Lamotrigine (LTG), a novel anticonvulsant, which has not been adequately assessed for its antineuralgic properties. It has a bimodal mechanism of action:

• inhibits the release of glutamate and aspartate by blocking voltage-sensitive sodium channels

• antagonistic at neuroexcitatory N-methyl-d-aspartate receptors.

It can also acts at and inhibits calcium channels to enhance the gamma- Aminobutyric acid (GABA) synthesis. GABA is an inhibitory amino acid neurotransmitter that decreases neural membrane action potentials and therefore decreases nerve excitability. Glutamate has been implicated in the mechanisms contributing towards phenomenon of chronic pain, such as sensitisation and wind up. LTG through its inhibition of pathological release of glutamate, has the potential towards management of chronic pain, particularly of neuropathic origin.

Lamotrigine, therefore has the potential to be a promising new treatment for TGN. ;

Study Design

Allocation: Non-Randomized, Endpoint Classification: Safety/Efficacy Study, Intervention Model: Crossover Assignment, Masking: Single Blind (Subject), Primary Purpose: Treatment

Related Conditions & MeSH terms

• Neuralgia
• Trigeminal Neuralgia

• NCT number: NCT00913107
• Study type: Interventional
• Source: University of Malaya
• Status: Completed
• Phase: Phase 2/Phase 3
• Start date: September 2007
• Completion date: June 2008