Lamotrigine with carbamazepine

The nurse may give lamotrigine without regard to meals. However, it is important to give carbamazepine with meals to decrease gastric upset. The nurse can crush the tablets if the patient has difficulty swallowing. However, it is important not to crush or chew extended-released carbamazepine... 

Pharmacotherapy is the cornerstone of acute and maintenance treatment of bipolar disorder. Mood-stabilizing drugs are the usual first-choice treatments and include lithium, divalproex, carbamazepine, and lamotrigine. Atypical antipsychotics other than clozapine are also approved for treatment of acute mania. Lithium, lamotrigine, olanzapine, and aripiprazole are approved for maintenance therapy. Drugs used with less research support and without Food and Drug Administration (FDA) approval include topiramate and oxcarbazepine. Benzodiazepines are used adjunctively for mania. 

Studies suggest that as monotherapy for partial seizures, lamotrigine is as effective as carbamazepine and phenytoin lamotrigine may be better tolerated. Clinical data suggest that oxcarbazepine is as effective as phenytoin, valproic acid, and immediate-release carbamazepine, with perhaps fewer side effects. 

Several other therapeutic effects of sodium channel blockers have been suggested. Most of these stem from clinical activities of approved anticonvulsants and antiarrhythmics with sodium channel blocking activity. Beneficial effects of sodium channel blockers for the treatment of bipolar disease are suggested by clinical data with lamotrigine [63-67], phenytoin [68], topiramate [69], and carbamazepine [70,71]. In addition, clinical studies with lidocaine suggest efficacy in the treatment of tinnitus [72] and, as an inhaled formulation, in the suppression of cough [73,74]. 

While there are no absolute contraindications to lithium, patients with advanced kidney disease or unstable fluid/ electrolyte balance may be more safely treated with an alternative mood stabilizer, such as carbamazepine, valproate, lamotrigine, or olanzapine. 

LAMOTRIGINE 1. CARBAMAZEPINE 2. OXCARBAZEPINE 1. Cases of t levels of an active metabolite of carbamazepine with toxicity 2. Case of toxicity with oxcarbazepine Uncertain Be aware watch for early features of toxicity of carbamazepine and oxcarbazepine... 

Pharmacodynamic interactions also occur. In particular, the adverse effects of any drug can be increased by other drugs with similar properties. One example is the reciprocal potentiation of the neurotoxic effects of carbamazepine and lamotrigine in patients taking a combination of these drugs (180). Some drugs (for example ciclosporin, clozapine) have a proconvulsant effect and can reduce the efficacy of antiepileptic drugs. 

Carbamazepine toxicity with lamotrigine pharmacokinetic or pharmacodynamic interaction Epilepsia... 

Nieto-Barrera M, Brozmanova M, CapoviUa G, Christe W, Pedersen B, Kane K, O Neill F Lamictal vs. Carbamazepine Study Group. A comparison of monotherapy with lamotrigine or carbamazepine in patients with... 

Several authors have provided insight into the putative MBS receptor based on their structure-activity data. As noted by Unverferth et al. (281), there have been several attempts to postulate a general pharmacophore for the different anticonvulsant classes, all of which are anti-MES in animal studies and are, or have the potential to be, effective in generalized tonic-clonic seizures. These include benzodiazepines (282) barbiturates (283) triazolines (284) semicarbazones (248-261) and enami-nones (286-288), respectively and for different compounds with similar anticonvulsant profiles (289-292). The Unverferth model (Fig. 6.11) provides an excellent representation of the current anticonvulsants phenytoin (1), carbamazepine (2), lamotrigine (11), zonisamide (13), and rufinamide (60). Remace-mide (58) is also included as a possible candidate (Fig. 6.12). 

The anticonvulsant action of valproate may prevent ECT treatment from being effective by preventing seizure activity. This is also a theoretical/practical concern with carbamazepine, gabapentin, lamotrigine, and topiramate. As a rule of thumb, the co-administration of an anticonvulsant and ECT should be considered very cautiously ... 

Besag FMC, Berry DJ, Pool F, Newbery JE, Subel B, Carbamazepine toxicity with lamotrigine a pharmacokinetic or pharmacodynamic intsTaction Epilepsia (1998) 39,183-7. 

Unlike carbamazepine, oxcarbazepine appears not to have marked en-zyme-indueing properties so that it would not be expected to have as great an effeet on the metabolism of other antiepileptics. However, oxcarbazepine does appear to act as an inhibitor of the cytochrome P450 isoenzyme CYP2C19 at high concentrations and therefore may raise phenytoin levels (see Phenytoin + Carbamazepine , p.554, for more on this mechanism). Other antiepileptics can increase the metabolism of the active metabolite of oxearbazepine, monohydroxyoxcarbazepine. The situation with lamotrigine is not clear. In one study lamotrigine appeared to de-erease the metabolism of oxcarbazepine but another study found no phar-maeokinetie interaetion. 

Any changes in the pharmacokinetics of oxcarbazepine brought about by other antiepileptics seem to be of minimal clinical relevance. However, the clinical relevance of the increase in the active metabolite monohydroxyoxcarbazepine with lamotrigine requires further study. In addition, there is the theoretical risk that monohydroxyoxcarbazepine levels might rise to toxic levels if carbamazepine or phenytoin were withdrawn. For mention that there may be an increase in adverse effects if oxcarbazepine is used with felbamate, see Oxcarbazepine +Felbamate , p.545. 

There appears to be no pharmacokinetic interaction between pregabalin and carbamazepine, gabapentin, lamotrigine, phenobarbital, phenytoin, topiramate, valproate, alcohol, lorazepam, or oxycodone. However, the impairment of cognitive and gross motor function caused by oxycodone was additive with pregabalin, and pregabalin may potentiate the effects of alcohol and lorazepam. 

Brodie MJ, Wilson EA, Wesche DL, Alvey CW, F dinitis EJ, Posvar EL, Hounslow NJ, Bron NJ, Gibson GL, Bockbrader HN Pregabalin drug intemction studies lack of effect on the pharmacokinetics of carbamazepine, phenytoin, lamotrigine, and val M oate in patients with p ial epilepsy. Epilepsia (2005) 46, 1407-13. 

Comparative studies Carbamazepine versus lamotrigine Carbamazepine and lamotrigine have been compared in 125 elderly patients with epilepsy using the modified Side Effect and Life Satisfaction Inventory and the Liverpool Adverse Event Profile in an international double-blind study [4 ]. Neither drug caused significant changes in health-related quality of life after 40 weeks. A borderline difference in the Side Effect and Life Satisfaction Inventory Dysphoria subscores favored lamotrigine. 

Saetre E, Abdelnoor M, Perucca E, Taubpll E, Isojarvi J, Gjerstad L. Antiepileptic drugs and quality of life in the elderly results from a randomized double-blind trial of carbamazepine and lamotrigine in patients with onset of epilepsy in old age. Epilepsy Behav 2010 17(3) 395 01. 

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