[Pharmacological treatment of trigeminal neuralgia: systematic review and metanalysis.]

Trigeminal neuralgia is a syndrome of chronic pain, characterized by paroxysms of excruciating pain which dramatically affect patients' quality of life. Systemic drug therapy is the first line treatment for this disease. This study aimed at evaluating efficacy, safety and tolerability of several pharmacologic treatments offered to trigeminal neuralgia patients, trying to supply evidences for clinical practice recommendations and to identify the needs for further research.

Randomized controlled clinical trials on the analgesic effects of drugs prescribed for trigeminal neuralgia were evaluated. All of them were published until July 2003. Statistical analysis was accomplished with the support of Review Manager 4.2.2 software (Cochrane Collaboration, 2003).

Metanalisys results suggest that carbamazepine is more efficient than placebo. In three controlled studies comparing lamotrigine, topiramate and 0.5% proparacaine hydrochloride, only lamotrigine was superior to placebo. Dextromethorphan was compared to low-dose lorazepam, with increased pain with dextromethorphan. Three studies have compared carbamazepine to tizanidine, tocainide and pimozide, and only pimozide was superior to carbamazepine.

Carbamazepine is still the drug of choice for treating trigeminal neuralgia, being lamotrigine and pimozide indicated for cases refractory to conventional therapy. In addition, further studies are needed to determine future therapeutic options.