Epilepsy phenobarbital

Phenobarbital Epilepsy Drowsiness, depression of suckling reflex... 

The anticonvulsant primidone (1035) resembles phenobarbital but lacks the 2-oxo substituent. It was introduced in 1952 and has remained a valuable drug for controlling grand mal and psychomotor epilepsy. As might be expected, primidone is metabolized to yield phenobarbital (1034 X = 0) and C-ethyl-C-phenylmalondiamide (1036), both of which have marked anticonvulsant properties however, primidone does have intrinsic activity and an appropriate mixture of its metabolites has only a fraction of its activity (73MI21303). Primidone may be made in several ways, of which desulfurization by Raney nickel of the 2-thiobarbiturate (1034 X = S) or treatment of the diamide (1036) with formic acid (at 190 °C) seem to be the most satisfactory (54JCS3263). 

Barbiturates. The hrst barbiturate, barbital, was introduced in 1903 and was followed a few years later by phenobarbital. The barbiturates effectively relieve anxiety, but they are never used as anxiolytics today due to toxicity and abuse concerns. However, several barbiturates, including phenobarbital (Luminal), secobarbital (Seconal), and pentobarbital (Nembutal), remain available and are occasionally used to treat epilepsy and rarely to manage acute alcohol withdrawal. 

Phenobarbitone is used to treat epilepsy, migraine headache, dental infections, pregnancy vomiting, tetanus, enuresis, chorea, pre and post operative sedation, hypertension, anxiety states, neurosis, and in the treatment of drug and alcohol addiction. This drug is also called phenobarbital. 

Phenobarbital exhibits relaxant, soporific, and anticonvulsant activities. It is widely used in treating epilepsy, chorea, and spastic paralysis, and is used as a component of a large number of combined drugs, valocordin and corvalol in particular. The most common synonyms are luminal, fenemal, hypnotal, and several others. 

Barbiturates Phenobarbital- (PB) Status epilepticus Epilepsy, all forms Tonic-clonic 40 to 60 Liver 25% eliminated unchanged in urine... 

Epilepsy, monotherapy Indicated for conversion to monotherapy in adults with partial seizures who are receiving treatment with carbamazepine, phenytoin, phenobarbital, primidone, or valproate as the single antiepileptic drug (AED). 

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... 

At present, phenobarbital and primidone are considered as alternative drugs for the treatment of partial seizures and for generalized tonic-clonic epilepsy. They are judged to be less effective than carbamazepine and phenytoin. 

Convulsions associated with fever often occur in children 3 months to 5 years of age. Epilepsy later develops in approximately 2 to 3% of children who exhibit one or more such febrile seizures. Most authorities now recommend prophylactic treatment with anticonvulsant drugs only to patients at highest risk for development of epilepsy and for those who have multiple recurrent febrile seizures. Phenobarbital is the usual drug, although diazepam is also effective. Phenytoin and carba-mazepine are ineffective, and valproic acid may cause hepatotoxicity in very young patients. 

Historically, alcohol has been used as an anxiety-reducing agent, both casually and in professional medical settings. In 1903, barbital was introduced as the first barbiturate to treat anxiety, and phenobarbital followed a few years later. Barbiturates have many side effects and addictive properties, and overdose can lead to coma and death. For these reasons, they are rarely used today, except to treat some forms of epilepsy. This class of drugs was eventually replaced by the benzodiazepines (see Chapter 4). 

Phenobarbital, mephobarbital and metarbital are the only oral anticonvulsants which are effective at sub-hypnotic levels. Many barbiturates are classified as Schedule II, III, or IV due to their high potential for overdose and dependence. Abrupt withdrawal may cause seizures, restlessness, trembling, and insomnia and may be fatal. Phenobarbital is used as an anticonvulsant for the treatment of epilepsy and in some combination medications for the relief of irritable bowel syndrome. 

Among the various other types of epilepsy are partial seizures which involve some involuntary muscle spasm or sensual disturbance without loss of consciousness. Phenobarbital, diazepam, phenytoin and carbamazepine are the most commonly used medications for this condition. As... 

The long-acting barbiturates phenobarbital (Luminal) and mephobarbital (Mebaral) are used medically to help a patient sleep. Another use is day-long sedation, a procedure that treats tension and anxiety. Furthermore, long-acting barbiturates are used with other drugs in the treatment of convulsive conditions like epilepsy. 

By 1912, von Mering and Fischer developed and commercially introduced a new barbiturate compound for sleep and anxiety called phenobarbital or Luminal. However, this medication quickly found its place as treatment for a very different medical condition, epilepsy, which is a condition of periodic, unprovoked convulsions or seizures. The main goal of epilepsy treatment is to decrease the frequency of seizures. Alfred Hauptmann discovered the anti-epileptic properties of phenobarbital accidentally. A 1912 report by Hauptmann described epileptic patients who were given phenobarbital for sedation and incidentally had fewer seizures. Seizures are caused by an abnormal impulse in the brain, which spreads and sends inappropriate message to the body. These messages result in... 

Jaina was diagnosed with a seizure condition known as epilepsy. Her doctor, Dr. Smith, prescribed a medication, phe-nobarbital, for her condition. He explained that phenobarbital is a controlled substance because it has the risk of being abused. Therefore, Dr. Smith used a special controlled substances prescription pad to write Jaina s prescription and included his DEA number on the prescription. 

Barbiturates are also used in infantile seizures that are not considered epilepsy. These seizures generally occur when an infant has a high fever, and therefore they are called febrile seizures. Phenobarbital is still commonly used to prevent seizures in infants, because scientists do not routinely study new drugs in infants and children. Because phenobarbital is... 

Phenobarbital (5-etbyl-5-phenylbarbituric acid) possesses specific usefulness in epilepsy. 

Another early example of the use of LC was in the analysis of diphenylhy-dantoin and phenobarbital levels in the plasma of a patient receiving these drugs for the management of epilepsy (25,26). As shown in Figure 2-29, by using LC the plasma was found to contain 8.5 fig of phenobarbital and 9.2 fig of diphenylhydantoin per milliliter. The LC method, additionally, has several advantages over other methods. These advantages include faster separation, lack of derivatization, better sample stability, and smaller sample size (25,26). 

Behavioral and psychiatric disturbances are not uncommon (31). Although epilepsy is itself associated with an increased risk of such disturbances, drugs play an important role. Phenobarbital-induced behavioral disturbances, especially hyperkinesia, are especially common in children, with an incidence of 20-50% and need for drug withdrawal in 20-30% of cases, whereas it is unclear whether and to what extent adults are affected. 

Iivanainen M, Savolainen H. Side effects of phenobarbital and phenytoin during long-term treatment of epilepsy. Acta Neurol Scand Suppl 1983 97 49-67. 

Antiepileptics. Large doses of vitamin B6 can reduce serum levels of phenytoin and phenobarbital, and thus cause loss of control of epilepsy. Vitamin B6 in excess of 10 mg a day should be avoided. The antiepileptics phenytoin, phenobarbital and primidone can cause folate deficiency (resulting in... 

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