In controlling seizures

Administration of trimethadione (Tridione) may result in hematologic changes, such as pancytopenia (decrease in all the cellular components of the blood), leukopenia, aplastic anemia, and thrombocytopenia Also reported are various types of skin rashes, diplopia (double vision), vomiting, changes in blood pressure, CNS depression, photosensitivity, and fatal nephrosis. Because these dm have been associated with serious adverse reactions and fetal malformations, they should be used only when other less toxic dm are not effective in controlling seizures. The oxazolidinediones may precipitate a tonic-clonic seizure... 

Anticonvulsants, used in controlling seizures, are analyzed on Ci8 columns at UV, 220 nm, eluting with 40% MeOFI/water. They are also common drugs of abuse and are monitored for in toxicology laboratories. 

In animals, the profile of antiseizure properties for CBZ is similar to that of phenytoin. CBZ is effective in the maximal electroshock (MES) test (electrically induced seizure test) but is ineffective against pentylenetetrazole-induced seizures. It is not effective for absence or myoclonic seizures and, indeed, may exacerbate their onset (30,41). Like phenytoin, CBZ acts on voltage-dependent sodium channels to prevent the spread of seizures. CBZ depresses synaptic transmission in the reticular activating system, thalamus, and limbic structures. In a double-blind, crossover study in patients whose seizures were not controlled completely by combinations of AED, CBZ was equal in efficacy to phenobarbital and phenytoin in controlling seizure frequency, and side effects were minimal. 

OXAZOLIDINEDIONES. The oxazolidinediones are used only when other, less-toxic dm have not been effective in controlling the seizure disorder because they have been associated with fetal abnormalities and serious adverse reactions. 

It has become clear that drugs which are effective in protecting mice against PTZ are effective in absence seizures while those able to control the tonic response to maximal electroshock are effective in tonic-clonic seizure. Some drugs are effective in only one test and clinical condition whilst a few are active in both (Table 16.1). Experimental focal seizures are indicative of partial seizures. 

Ventilate the patient. There may be an increase in airway resistance due to constriction of the airway and the presence of secretions. If breathing is difficult, administer oxygen. As soon as possible administer of atropine alone or in combination with pralidoxime chloride (2-PAMC1) or other appropriate oxime. Diazepam may be required to prevent or control severe convulsions. If diazepam is not administered within 40-minutes postexposure, then its effectiveness at controlling seizures is minimal. 

Following acute exposure to cyclodiene organochlorine pesticides, seizures and respiratory depression may occur (Ellenhom 1988 Proctor et al. 1988). Benzodiazepines (e.g., diazepam or lorazepam) or other anticonvulsant medications (e.g., phenobarbital) have been commonly used to control seizures (Ford 1993). Organochlorines may sensitize the myocardium to the proarrhythmic effects of adrenergic amines, potentially resulting in initiation of ventricular fibrillation (TOMES 1994). 

Colonazepam belongs to the class of 1,4-benzodiazepines that has been found to be therapeutically effective in controlling minor motor seizures i.e., petitmal epilepsy in humans ... 

While regular monitoring of plasma phenytoin levels can result in improved seizure control, the benefit derived from measuring other commonly prescribed anticonvulsant drugs is difficult to assess. Phenobarbitone, primidone, and carbamazepine will be discussed briefly. 

Discontinue as soon as the desired effect is obtained. Repeat doses are dependent on the continuing presence of the patellar reflex and adequate respiratory function. Acute nephritis in chiidren 20 to 40 mg/kg IM as needed to control seizures. Dilute the 50% concentration to a 20% solution and give 0.1 to 0.2 mL/kg. 

With some drugs, particularly those with a long half life, a loading dose may be useful in order to achieve a therapeutic level more rapidly. For example, the half-life of phenobarbital in the neonate is long, approximately 120 hours, with steady-state concentrations achieved in two to three weeks. A slowly-infused loading dose can be efficacious in achieving seizure control within minutes, typically followed by maintenance infusion and subsequent transition to oral therapy daily. 

The first effective treatment of seizure disorders was the serendipitous finding in 1857 that potassium bromide could control seizures in some patients. Even though side effects were troublesome, the bromides were widely used for many years. Phenobarbital was introduced as a treatment for epilepsy in 1912 and was immediately shown to be markedly superior to bromides. While other barbiturates were synthesized and used, none were shown to be superior to phenobarbital, and the latter compound is still used. A chemically related... 

Mechanism of Action An anticonvulsant agent that increases the seizure threshold, suppresses paroxysmal spike-and-wave pattern in absence seizures and depresses nerve transmission in the motor cortex. Therapeutic Effect Controls absence (petit mal) seizures. 

All barbiturates (except phenobarbital) except when used to control seizures Are highly addictive and cause more adverse effects than most sedative or hypnotic drugs in elderly patients. High... 

Some developed seizure disorders characterized by vomiting, loose stools, irritability, diarrhea elevated blood B values of 2.6-8.5 mg B/L vs. <0.6 in controls. When preparation withheld, seizures stopped and children remained well for at least 5 years (13)... 

Phenobarbital is useful in the treatment of partial seizures and generalized tonic-clonic seizures, although the drug is often tried for virtually every seizure type, especially when attacks are difficult to control. There is little evidence for its effectiveness in generalized seizures such as absence, atonic attacks, and infantile spasms it may worsen certain patients with these seizure types. 

Valproate is very effective against absence seizures and is often preferred when the patient has concomitant generalized tonic-clonic attacks. Valproate is unique in its ability to control certain types of myoclonic seizures in some cases the effect is very dramatic. The drug is effective in generalized tonic-clonic seizures, especially those that are primarily generalized. A few patients with atonic attacks may also respond, and some evidence suggests that the drug is effective in partial seizures. 

Seizures, though recognized as a complication of chlorpromazine treatment, were so rare with the high-potency older drugs as to merit little consideration. However, de novo seizures may occur in 2-5% of patients treated with clozapine. Use of an anticonvulsant is able to control seizures in most cases. 

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