What is the role of Lamictal (lamotrigine) in treating bipolar disorder?

From the Guidelines

Lamictal (lamotrigine) is an effective medication for treating bipolar disorder, particularly for preventing depressive episodes in bipolar I and II disorders, as evidenced by its approval for maintenance therapy in adults 1. The typical treatment begins with a low dose of 25mg daily for two weeks, then gradually increases by 25-50mg every 1-2 weeks until reaching a therapeutic dose of 100-200mg daily (sometimes up to 400mg if needed) 1. This slow titration is crucial to reduce the risk of serious skin rashes, including Stevens-Johnson syndrome. Key points to consider when using Lamictal for bipolar disorder include:

• It works primarily as a mood stabilizer by modulating glutamate and calcium channels in the brain, helping to prevent mood swings without causing sedation or weight gain that other mood stabilizers might cause 1.
• It's particularly valuable for patients who struggle more with depressive episodes than manic ones, as supported by the study of Chang et al. (2006) mentioned in 1.
• Common side effects include headache, dizziness, blurred vision, and nausea.
• Patients should immediately report any rash, fever, or flu-like symptoms to their doctor.
• Lamictal is often used alone or in combination with other mood stabilizers depending on the specific presentation of bipolar symptoms, and requires regular follow-up with a psychiatrist to monitor effectiveness and side effects, as recommended in 1. In terms of maintenance treatment, lithium or valproate should be used for at least 2 years after the last episode of bipolar disorder, with the decision to continue maintenance treatment after 2 years preferably done by a mental health specialist 1.

From the Research

Role of Lamictal in Treating Bipolar Disorder

• Lamotrigine (Lamictal) is a well-established anticonvulsant agent that has shown efficacy in the prevention of mood episodes in adult patients with bipolar I disorder 2, 3.
• The mechanism of action of the drug in patients with bipolar disorder may be related to the inhibition of sodium and calcium channels in presynaptic neurons and subsequent stabilisation of the neuronal membrane 2, 3.
• Lamotrigine monotherapy significantly delayed time to intervention with additional pharmacotherapy or electroconvulsive therapy for any new mood episode (mania, hypomania, depression and mixed episodes), compared with placebo, in two large, randomised, double-blind trials of 18 months' duration 2, 3.

Efficacy in Preventing Mood Episodes

• Lamotrigine was significantly superior to placebo at prolonging time to intervention for depression 2, 3.
• Lamotrigine showed efficacy in delaying manic/hypomanic episodes in pooled data only, although lithium was superior to lamotrigine on this measure 2, 3.
• Lamotrigine has been shown to be an effective maintenance therapy for patients with bipolar I disorder, significantly delaying time to intervention for any mood episode 2, 3.

Acute Treatment of Bipolar Depression

• Lamotrigine has shown efficacy in the acute treatment of patients with bipolar depression but has not demonstrated efficacy in the treatment of acute mania 2, 3, 4, 5, 6.
• The treatments with the best evidence for efficacy in bipolar depression are selective serotonin reuptake inhibitors (SSRIs) and lamotrigine 4.
• A combination of an atypical antipsychotic and either an SSRI or lamotrigine may provide a useful first-line treatment for depressed bipolar disorder patients 4.

Safety and Tolerability

• Lamotrigine was generally well tolerated in maintenance studies with the most common adverse events being headache, nausea, infection and insomnia 2, 3.
• The incidence of serious rash with lamotrigine treatment was 0.1% in all studies of bipolar disorder and included one case of mild Stevens-Johnson syndrome 2, 3.
• Lamotrigine did not appear to cause bodyweight gain and, unlike lithium, generally does not require monitoring of serum levels 2, 3.