Posted by rjlockhart on April 24, 2007, at 23:01:18
In reply to Re: a rash? » rjlockhart, posted by Phillipa on April 24, 2007, at 22:55:57
Q. How is lamotrigine (Lamictal) used as an antidepressant?
A. Lamotrigine is a novel anticonvulsant with an unknown mechanism of action. There is some evidence that lamotrigine may block 5-HT3 receptors and may also potentiate dopaminergic transmission. This agent has been FDA-approved for the treatment of bipolar depression. Two small studies have recently looked at lamotrigine as an adjunctive agent in the treatment of unipolar depression. In a study of 23 patients who had experienced at least one episode of treatment-resistant major depression as a component of unipolar major depression or bipolar II disorder, subjects were randomized to receive fluoxetine (Prozac) and either lamotrigine or placebo (Barbosa et al., 2003). Although both unipolar and bipolar II patients experienced improvement with lamotrigine and fluoxetine on the Clinical Global Impressions (CGI) scale, lamotrigine failed to separate statistically from placebo on the Hamilton Rating Scale for Depression (HAM-D) and the Montgomery-Asberg Depression Rating Scale (MADRS).
In another double-blind, placebo-controlled study, lamotrigine or placebo was administered to 40 outpatients concurrently taking paroxetine (Paxil) for acute depression (Normann et al., 2002). The dropout rate for this study was high, with only 24 completers. Upon completion of the nine-week study, both groups improved significantly relative to baseline, but there was no significant difference in HAM-D total scores when comparing lamotrigine and paroxetine to paroxetine and placebo. Nevertheless, lamotrigine did appear to result in significant improvement in HAM-D items 1 (depressed mood), 2 (guilt feelings) and 7 (work and interest), and in CGI-Severity of Illness (CGI-S) scores. Patients treated with lamotrigine and paroxetine appeared to show faster onset of antidepressant action and required fewer days of treatment with benzodiazepines. Notably, two of the subjects treated with lamotrigine terminated their involvement prematurely due to neutropenia, and another withdrew because of a benign rash that resolved after discontinuation of lamotrigine. More rigorous studies are clearly needed to address the possible benefits of lamotrigine for the treatment of unipolar depression. Interestingly, lamotrigine has been included as a possible treatment for patients with chronic major depression in whom more traditional pharmacotherapy, psychotherapy and electroconvulsive therapy have failed (Trivedi and Kleiber, 2001).
In summary, evidence of the efficacy of lamotrigine as augmentation in the treatment of major depression is inconclusive, preliminary and must be replicated by larger, randomized, blinded, controlled studies. Large-scale, double-blind, placebo-controlled trials are also warranted to address the potential use of lamotrigine as monotherapy for major depression.
References
Barbosa L, Berk M, Vorster M (2003), A double-blind, randomized, placebo-controlled trial of augmentation with lamotrigine or placebo in patients concomitantly treated with fluoxetine for resistant major depressive episodes. J Clin Psychiatry 64(4):403-407.
Normann C, Hummel B, Scharer LO et al. (2002), Lamotrigine as adjunct to paroxetine in acute depression: a placebo-controlled, double-blind study. J Clin Psychiatry 63 (4):337-344].
Trivedi MH, Kleiber BA (2001), Algorithm for the treatment of chronic depression. J Clin Psychiatry 62(suppl 6):22-29.
What is 5HT3 Receptors, do they make you in a bad mood.
poster:rjlockhart
thread:753159
URL: http://www.dr-bob.org/babble/20070419/msgs/753178.html