Tremor lamotrigine

Lithium augmentation of antidepressants, carbamazepine, lamotrigine, and valproate can improve response, but it may increase the risk of sedation, weight gain, GI complaints, and tremor. 

Side effects. The most common side effects are headache, nausea and vomiting, diplopia, dizziness, ataxia and tremor. There are also reports that lamotrigine can cause such psychiatric side effects as aggression, agitation, confusion, hallucinations and psychosis, some of these effects possibly being associated with a reduction in the glutamatergic system. Rashes are a frequent side effect, occurring in up to 5% of patients. Usually rashes are mild but occasionally can be severe and amount to a Stevens-Johnson syndrome. The severe rash occurs more commonly in children. 

The adverse effects of lithium in elderly patients include cognitive status worsening, tremor, and hypothyroidism. The authors suggested that divalproex is also useful in elderly patients with mania and that concentrations of divalproex in the elderly are similar to those useful for the treatment of mania in younger patients. They noted that carbamazepine should be considered a second-line treatment for mania in the elderly. A partial response would warrant the addition of an atypical antipsychotic drug. For bipolar depression, they recommended lithium in combination with an antidepressant, such as an SSRI. They also noted that lamotrigine may be useful for bipolar depression. Electroconvulsive therapy (ECT) may also be useful, but there have been no comparisons of ECT and pharmacotherapy in elderly patients with bipolar depression. 

In 126 patients with carbamazepine-resistant or valproate-resistant epilepsy given lamotrigine, 50% during add-on therapy and 53% during lamotrigine monotherapy had at least 50% reduction in total seizures (15). There were adverse events in 49 patients, including respiratory tract infections n — 11), dizziness (n — 8), headache (n = 7), diplopia (n = 5), tremor (n = 5), somnolence (n — 4), insomnia (n = 4), nausea (n — 4), and weakness (n = 3). Treatment was discontinued in nine patients because of adverse events, in five cases because of rash. 

The most common adverse effects of lamotrigine include dizziness, weakness, headache, diplopia, ataxia, blurred vision, and somnolence (SEDA-18, 65) (SEDA-20, 63) (19). These effects resemble those seen with carbamaze-pine and can result from an adverse pharmacodynamic interaction. Tolerability is better when lamotrigine is given as monotherapy or with drugs other than carbama-zepine however, tremor develops in some patients taking valproate in combinations (SEDA-18, 66). During monotherapy, serum lamotrigine concentrations associated with intolerable adverse effects (mostly headache, dizziness, and ataxia) were 0.4-18.5 qg/ml and overlapped widely with those tolerated in other patients (20). 

Lamotrigine is reported to be generally well tolerated in maintenance studies, with the most common adverse events being headache, nausea, insomnia, and, to a lesser extent, tremor. Incidences of diarrhea and tremor are lower with lamotrigine than with litbium. 

Myoclonic seizures consist of sudden, very brief, jerking contractions that may involve the entire body or be confined to limited areas, such as the face and neck. The contractions may affect Individual muscles or groups, with simultaneous contraction of both extensor and flexor muscles. These seizures occur In all age groups, with symptoms ranging from rapid tremors to falling down. No loss of consciousness Is detectable because of the brief duration of the seizure. Myoclonic seizures often occur In combination with other seizure types. Valproate and clonazepam are used most often to treat myoclonic seizures lamotrigine and topiramate also have shown some efficacy. 

The serum levels of lamotrigine can be markedly increased by valproate. Concurrent use has been associated with skin rashes, tremor and other toxic reactions. Lamotrigine has been found to cause small increases, decreases or no changes in valproate levels. 

Not fully understood. It is thought that valproate reduces lamotrigine glu-curonidation by competitive inhibition, which results in a decreased lamotrigine clearance.Raised lamotrigine levels have been implicated in the development of rash. Increased valproate clearance may be due to enzyme induction. Tremor may be the result of a pharmacodynamic interaction. ... 

Reutens DC, Duncan JS, Patsalos PN. Disabling tremor after lamotrigine with sodium valproate. Lancet (1993) 342,185-6. 

Voudris K, Mastroyianni S, Skardoutsou A, Katsarou E, Mavrommatis P. Disabling tremor in epileptic children receiving sodium valproate after addition of lamotrigine. P2197. EurJ Neurol(2003) 10(Suppl. 1), 180. 

Comparative studies In an open study in patients with type I bipolar disorder randomized to lithium ( = 78) or lamotrigine (n = 78) and followed for up to 5 years, there was no overall difference, although lamotrigine was non-significantly better at preventing episodes of depression and lithium better at preventing episodes of mania [3 ]. Patients taking lithium had more adverse reactions, particularly diarrhea, tremor, polyuria, and thirst (serum concentrations maintained at 0.5-1.0 mmol/1). 

Observational studies Lamotrigine has been evaluated in a study that included an open, 1-week screening phase, a 20-week escalation phase, and a 12-week maintenance phase in 54 children aged under 13 years who had newly diagnosed absence epilepsy and had not previously been treated with antiepileptic drugs [138 ]. Rash was reported in six patients (11%), urticaria in one patient (2%), and pruritus in two patients (4%). None of these events was serious or resulted in premature withdrawal. Three patients had adverse events that led to premature withdrawal increased seizure activity in one, tremor in one, and vomiting and dizziness in one patient. 

Comparative studies Lamotrigine versus divalproex sodium In a 12-week, doubleblind, randomized, placebo-controlled comparison of lamotrigine and divalproex sodium in 25 patients with schizophrenia or schizoaffective disorders stabilized on an antipsychotic drug, there were no differences in any outcome measure [143 ]. Very few patients reported adverse effects. Two patients randomized to divalproex sodium and placebo reported depression and suicidal thought or tremors respectively. Two patients (one taking lamotrigine and one... 

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