Ricerc@Sapienza

Background: It is widely agreed that carbamazepine and oxcarbazepine are highly effective in
the long-term treatment of trigeminal neuralgia. However, the tolerability of these drugs across
the different aetiologies of trigeminal neuralgia is still undetermined.
Methods: In this retrospective, real-world study, we assessed the effectiveness and tolerability of
carbamazepine and oxcarbazepine in a large cohort of patients with classical (254 patients),
secondary (60 patients) and idiopathic (40 patients) trigeminal neuralgia. We analysed data using
a propensity score analysis to account for selection bias; frequencies of side effects associated to
carbamazepine and oxcarbazepine were calculated by adjusting data with the inverse probability
of treatment weighting.
Results: The initial proportion of responders was 88.3% with carbamazepine, and 90.9% with
oxcarbazepine. The number of refractory patients was significantly higher in idiopathic (15%) and
secondary forms (27%) than in classical trigeminal neuralgia (6%), (p<0.05). In 53 patients
treated with carbamazepine (29.6%) and in 22 treated with oxcarbazepine (12.6%), major side
effects caused treatment interruption or dosage reduction to an unsatisfactory level. Side effects
occurred more frequently in patients treated with carbamazepine (43.6%) than with
oxcarbazepine (30.3%, p<0.0001). The frequency of treatment discontinuation was higher in
patients with secondary and idiopathic forms than in those with classical trigeminal neuralgia
(p<0.05).
Conclusions: Our real-world study show that carbamazepine and oxcarbazepine are effective in
most patients with trigeminal neuralgia; nevertheless, side effects are still a major issue,
particularly in patients with secondary and idiopathic trigeminal neuralgia.