Pregabalin as an add-on Therapy to Carbamazepine in Trigeminal Neuralgia Patients

Trigeminal neuralgia is a very painful condition associated with paroxysmal severe episodes of pain. Carbamazepine has been the first line of drug for Trigeminal Neuralgia. However, there are several adverse effects linked with Carbamazepine like drowsiness, accommodation disorders, hepatitis, derangement in hepatic enzymes, renal dysfunction. Pregabalin which is an established drug in neuropathic pain has better pharmacokinetic nature which allows for easy management and rapid dose escalation to therapeutic doses. There have been only few trials evaluating efficacy of Pregabalin in classical trigeminal neuralgia. Thus, the present study is designed to evaluate the efficacy of Pregabalin as an add-on therapy to carbamazepine in patients suffering from Trigeminal Neuralgia. In present trial 50 patients fulfilling the exclusion and inclusion criteria will be recruited in two arms that is test group and the control group. The test group will be prescribed carbamazepine along with fixed dose of Pregabalin 75mg twice daily while the control group will be prescribed carbamazepine only. The dose of carbamazepine will be titrated in both groups as per patients need. The outcome regarding pain relief, quality of life and adverse effects and mean dose of carbamazepine required in both groups will be evaluated.

AIM

Evaluation of Efficacy of Pregabalin as an add on therapy with Carbamazepine in patients with trigeminal neuralgia.

OBJECTIVES

Primary objectives-

1. To compare the change in pain intensity in both groups.

Secondary objectives-

1. To evaluate the mean dose of carbamazepine used in both the groups.
2. To evaluate quality of life.
3. To evaluate the patient satisfaction in both groups.
4. To evaluate the need for additional pain medicine in both groups.

STUDY DESIGN

A randomized clinical trial will be conducted in department of Oral Medicine and Radiology, Post Graduate Institute of Dental Sciences, Rohtak.

STUDY SETTING

Hospital based study - Patients diagnosed with Trigeminal neuralgia will be recruited in study from regular OPD of the department of Oral Medicine and Radiology.

STUDY PERIOD

This study will be completed in 1 year.

STUDY SUBJECTS

Patients diagnosed with classical Trigeminal neuralgia will be recruited in the study from regular OPD of the Department of Oral Medicine and Radiology, PGIDS, Rohtak, Haryana. A total of 50 patients would compromise; Test group (n=25) and Control group (n=25).

METHOD OF RECRUITMENT Patient will be randomly allocated to test and control groups by using simple random sampling.

INTERVENTION

Clinically and MRI proven cases of classical Trigeminal neuralgia will be randomly and equally divided into test group and control group. The selected subjects will be divided into two groups.

TEST GROUP

Test group will be administered carbamazepine+pregabalin with fixed dose of pregabalin 75mg BD and carbamazepine being titrated as per patients's need and follow up done after 1 week with subsequent follow up at 2,4,6 and 8 weeks.

CONTROL GROUP

In control group all the armamentarium and procedure will remain same except that dose titration of carbamazepine is done till patient is relieved of pain.

Both groups will be assessed for the following parameters: intensity of pain, at the baseline ,1st week, 2nd week, 4th week ,6th week and 8th weeks interval.

Eligibility Criteria:
INCLUSION CRITERIA

* Patients diagnosed with Trigeminal neuralgia with classical types without concomitant pain as per ICHD-II.
* Patient's consent for participation in this study.

EXCLUSION CRITERIA

* Pregnant and lactating women
* Patients on anti-depressants like sodium valproate
* History of excessive alcohol intake
* Hepatic or renal insufficiency
* Known tolerance/allergy to study drug
* Non -compliant during screening period
* Any other hepatic microsomal enzyme inhibitors (to avoid risk for toxicity)