Tiagabine Carbamazepine

Hogan RE, Bertrand ME, Deaton RL, Sommerville KW. Total percentage body weight changes during add-on therapy with tiagabine, carbamazepine and phenytoin. Epilepsy Res 2000 41(l) 23-8. 

Vigabatrin (not marketed in United States), tiagabine, topiramate, gabapentin, carbamazepine, lamotrigine... 

Outside of the evidence-based guidelines, other pharmacologic treatments are commonly used or avoided. For initial treatment of absence seizures, ethosuximide and valproate are commonly used, not only in the United Kingdom, but also in the United States. Zonisamide may be also used for initial treatment of absence and myoclonic seizures. In absence and myoclonic seizures, carbamazepine, oxcarbazepine, gabapentin, tiagabine, and pregabalin should be avoided, as they have been associated with an exacerbation of these types of seizures. 

Carbamazepine, phenytoin, valproate, gabapentin, lamotrigine, levetiracetam, tiagabine, topiramate, zonisamide... 

Anticonvulsants. Several antiseizure medicines have been studied in the treatment of PTSD, and some results have been encouraging. Open label studies, first with carbamazepine (800-1200 mg/day) and later with valproate (500-2000 mg/ day), demonstrated overall improvement in PTSD patients, though not for intrusive recollections per se. Recent open label studies of gabapentin, lamotrigine, tiagabine, and topiramate have suggested these anticonvulsants might also be helpful for some PTSD symptoms. 

Drugs that can decrease carbamazepine serum levels include charcoal, cisplatin, doxorubicin, felbamate, hydantoins, rifampin, phenobarbital, primidone, theophylline. The serum levels of oral contraceptives, haloperidol, bupropion, anticoagulants, felbamate, valproic acid, felodipine, tricyclic antidepressants, acetaminophen, ziprasidone, voriconazole, topiramate, tiagabine, olanzapine, and lamotrigine can be lowered by carbamazepine. 

Drugs that may affect tiagabine include carbamazepine, phenobarbital, phenytoin, primidone, and valproate. Valproate may be affected by tiagabine. 

II.e. 5.2. Interactions between first and second generation AEDs. Felbamate raises plasma concentrations of phenytoin, valproic acid and carbamazepine. Clearance of tiagabine, topiramate and zon-isamide is increased in the presence of an enzyme inducer. Vigabatrin reduces phenytoin concentrations after 4-5 weeks of comedication (via an unknown mechanism). For tiagabine, the elimination half-life may be reduced by 2-3 hours in the presence of an enzyme-induction AED. Lamotrigine elimination is slower if given with valproic acid. Topiramate reduces elimination of phenytoin. 

Other agents with anticonvulsant properties that may be of use m the treatment of bipolar disorder include topiramate, gabapentin, tiagabine and carbamazepine (Janicak et al., 2001). 

Partial seizures Carbamazepine Phenytoin Lamotrigine Valproic acid Oxcarbazepine Gabapentin Topiramate Levetiracetam Zonisamide Tiagabine Primidone, phenobarbital Felbamate... 

For simple and complex partial seizures and secondary generalized tonic-clonic seizures, the first line drugs are - carbamazepine, valproate and phenytoin. Second line drugs include - acetazolamide, clobazam, clonazepam, ethosuximide, felbamate, gabapentin, lamotrigine, levetiracetam, oxacarbamazepine, primidone, tiagabine, topiramate and vigabactin. 

BARBITURATES 1. CARBAMAZEPINE 2. LAMOTRIGINE 3. TIAGABINE 4. VALPROATE 5. ZONISAMIDE L levels of these antiepileptics Induction of metabolism Watch for poor response to these antiepileptics... 

Carbamazepine can decrease piasma ieveis of acetaminophen, ciozapine, benzodiazepines, dicumaroi, doxycyciine, theophyiiine, warfarin, and haioperidoi as weii as other anticonvuisants such as phensuximide, methsuximide, ethosuximide, phenytoin, tiagabine, topiramate, iamotrigine, and vaiproate... 

CYP450 3A4 inducers such as carbamazepine can lower the plasma levels of tiagabine... 

Clearance of tiagabine is increased if taken with an enzyme-inducing antiepileptic drug (e.g., carbamazepine, phenobarbital, phenytoin, primidone) and thus plasma levels are reduced however, no dose adjustments are necessary for treatment ot epilepsy as the dosing recommendations for epilepsy are based on adjunctive treatment with an enzyme-inducing antiepileptic drug... 

Visual field defects associated with various antiepUeptic drugs (carbamazepine, diazepam, gabapentin, pheny-toin, tiagabine, and vigabatrin) have been reviewed (19). The true frequency is unknown, but in a retrospective study in 158 patients with partial epilepsy visual field defects were detected in 21 (13%) 13 patients had concentric visual field constriction without subjective spontaneous manifestations. Of these 13 patients, 9 were taking vigabatrin. 

The rationale and use of modified-release formulations of antiepileptic drugs (carbamazepine, valproic acid, and tiagabine) have been reviewed (171). The authors concluded that modified-release formulations afford the advantages of better patient compliance, fewer adverse effects, and less fluctuation in plasma concentrations, making monitoring of drug concentrations easier. They concluded that these advantages should lead to better seizure control and improved quahty of life. 

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