Antipsychotics seizures

Antipsychotics are not indicated for the treatment of withdrawal, except when hallucinations or severe agitation are present (Naranjo and Sellers 1986), in which case they should be added to a benzodiazepine. In addition to their potential to produce extrapyramidal side effects, antipsychotics lower the threshold for seizures, which is particularly problematic during alcohol withdrawal. 

Other sedative-hypnotic medications, such as barbiturates, may play a useful role in severe withdrawal from this group of drugs. For example, in a case series of GBL withdrawal, use of intravenous pentobarbital in the range of 1-2 mg/kg/hour lowered the total requirement for intravenous lorazepam (Sivilotti et al. 2001). Antipsychotic medications are often used to reduce psychotic agitation. However, because antipsychotic medications lower the seizure threshold and may contribute to loss of central control of temperature leading to hyperthermia or neuroleptic malignant syndrome (NMS), they are not indicated as first-line medications for GHB withdrawal delirium (Dyer and Roth 2001 McDaniel and Miotto 2001 Sharma et al. 2001). If anti-... 

There is an increased risk of drug-induced seizures in all patients treated with antipsychotics. The highest risk for antipsychotic-induced seizures is with the use of CPZ or clozapine. Seizures are more likely with initiation of treatment and with the use of higher doses and rapid dose increases. 

Quetiapine (Seroquel). Another atypical antipsychotic, quetiapine has also been approved by the FDA for the treatment of acute mania. It is usually administered twice daily at doses of 150-750mg/day. Like its counterparts, quetiapine is a well-tolerated medication. Its common side effects are drowsiness, dizziness, and headache. It causes less weight gain than olanzapine or clozapine but more than ziprasidone or aripiprazole. Quetiapine also does not cause agranulocytosis nor does it increase the risk of seizures. It can occasionally cause mild changes in liver function tests, but these usually return to normal even if the patient continues taking quetiapine. 

Molindone (Moban). Molindone is another of the medinm potency antipsychotics. There are two featnres that set it apart. First, it is less prone to cansing weight gain than other antipsychotics. As a result, it is sometimes preferred for obese schizophrenia patients. Second, although typical antipsychotics do not necessarily cause seizures, they may make them more likely to occur in people who are already prone to seizures. There is some evidence to suggest that molindone may be the least likely antipsychotic to increase the vulnerability to seizures. For this reason, molindone is frequently used to treat patients with schizophrenia who also have epilepsy. 

Another serious side effect of clozapine is a risk of seizures. This mainly occurs at higher doses of the drug, and having a seizure is not necessarily a sufficient reason to stop clozapine permanently. If the clozapine has been especially helpful, an anticonvulsant can be added to protect against further seizures. Valproate (Depakote) may be best in this regard because it not only provides protection from seizures but also may help to relieve some of the symptoms of schizophrenia. Recently, it has become clear that two atypical antipsychotic drugs, clozapine and olanzapine, are associated with an increased risk for the development of type II diabetes. 

Largactil is a proprietary preparation of chlorpromazine, an aliphatic antipsychotic with marked sedation and moderate antimuscarinic and extrapyramidal side-effects. Serenace is a proprietary preparation of haloperidol, a butyrophenone antipsychotic with marked extrapyramidal side-effects, moderate sedation but not very likely to cause hypotension. Tegretol is a proprietary preparation of carbamazepine, an anti-epileptic drug indicated in partial and secondary generalised tonic-clonic seizures, primary generalised tonic-clonic seizures, trigeminal neuralgia and in the prophylaxis of bipolar disorder unresponsive to lithium. 

Seizures Bupropion is associated with a dose-related risk of seizures. Discontinue bupropion and do not restart in patients who experience a seizure while on treatment. Use extreme caution when bupropion is administered to patients with a history of seizure, cranial trauma, or other predisposition(s) toward seizure, or prescribed with other agents (eg, antipsychotics, other antidepressants, theophylline, systemic steroids) that lower seizure threshold. 

Concomitant medications - Many medications (eg, antipsychotics, antidepressants, theophylline, systemic steroids) and treatment regimens (eg, abrupt discontinuation of benzodiazepines) are known to lower seizure threshold. 

Use with caution in older patients with Parkinson s Disease (an atypical antipsychotic is recommended), seizure disorders, cardiovascular disease with conduction disturbance, hepatic encephalopathy, narrow-angleglaucoma, congenital prolonged O-T syndrome or drugs which prolong O-T interval. 

The risk of agranulocytosis and seizures limits use to patients who have failed to respond or were unable to tolerate treatment with appropriate courses of standard antipsychotics. 

Most conventional antipsychotics are associated with a dose-depen-dent risk of a lowered seizure threshold, although the incidence of seizures with most of these drugs is quite small (Devinsky et al. 1991). Of all the conventional antipsychotics, molindone and fluphenazine have been shown most consistently to have the lowest potential for this side effect (ltd and Soldatos 1980 Ohver et al. 1982). The atypical antipsychotic clozapine is associated with a dose-dependent risk of seizure. 

Clozapine. Clozapine produces seizures at a greater rate than other antipsychotics, especially in the dose range of 600 to 900 mg/day. Fortunately, these levels are substantially above the usual therapeutic range of 300 to 400 mg/day, but seizures can occur on lower doses, as well. A more rapid escalation of the clozapine dose may also predispose to the development of seizures. According to the drug s manufacturer, the reported incidence of seizures, based on daily dosage, is as follows ... 

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