Barbiturate drugs

Lehane, D.P. et al. 1976. Therapeutic drug monitoring Measurements of antiepileptic and barbiturate drug levels in blood by gas chromatography with nitrogen-selective detector. Ann Clin Lab Sci. 6 404. 

Sedation is an intermediate degree of CNS depression, while hypnosis is a degree of CNS depression similar to natural sleep. From the chemical point of view, soporific, sedative, and hypnotic drugs are classified as barbiturates, benzodiazepine hypnotics, and so on. Except for a few rare exceptions, any one of these compounds can be used for acquiring a sedative effect or state of sleep. Presently, the less toxic benzodiazepines are edging out the class of barbiturates more and more because of the possibility of chronic dependence associated with the use of barbiturates. Drugs of both classes are primarily CNS depressants, and a few of their effects, if not all, are evidently linked to action on the GABA-receptor complex. 

Barbiturate drugs like pentobarbital (Nembutal ), secobarbital (Seconal ), amobarbital (Amytal ), and phenobarbital are extremely potent sedatives that induce sleep, mostly non-REM sleep. However, barbiturates actually decrease the amount of REM sleep a person gets. Thus, if a person took a barbiturate as a sleep aid nightly for a week, the total amount of REM sleep would be significantly less than if he or she was not taking the drug. Then, when the person stopped taking the barbiturate, he or she would experience a severe REM... 

Amytal (a barbiturate drug), rotenone (a plant product commonly used as an insecticide), and piericidin A (an antibiotic) inhibit electron flow from the Fe-S centers of Complex I to ubiquinone (Table 19-4) and therefore block the overall process of oxidative phosphorylation. 

Barbituric acid (83), which is formally 2,4,6-trihydroxyprimidine, is extensively tautomeric (p. 1175). The barbiturate drugs are derivatives of the triketo form. Piperazine-2,5-dione (84) is a diamide based upon the pyrazine ring system. 

The researchers Joseph von Mering and Emil Fischer, a student of von Baeyer, developed the first barbiturate drug to be marketed. Fischer produced 5.5-diethylbarbituric acid, a hypnotic (medication to help patients sleep) and sedative (medication to relax people with constant nervousness and anxiety). This sedative/hypnotic drug was known by the trade names Barbital, Veronal, and Dorminal. Barbital proved to be a more effective sedative/hypnotic agent and replaced the class of drugs, sedative bromides, which were used at the time.14... 

Kastrup, E. K., ed. Sedatives and Hypnotics, Barbiturates. Drug Facts and Comparisons. St Louis Wolters Kluwers Health, 2005. 977-984. 

Other anticonvulsants include barbiturate drugs such as amobarbital (Amytal ), butabarbital (Butisol ), pentobarbital (Nembutal ), phenobarbital (Barbita, Luminal, Solfoton ), secobarbital (Seconol ), and thiopental (Pentothal ). These anticonvulsants are quite sedating and potentially addictive and are thus prescribed less often. 

Tuberculous patients lacking in liver N-acetyl transferase who are treated with isoniazid are likely to develop polyneuritis (39). An enzyme abnormality is also responsible for the precipitation of acute intermittent porphyria by the barbiturate drugs (40). Likewise, the rare hereditary resistance to coumarin anticoagulant drugs is thought to be due to an enzyme deficiency (41). 

Exposure to drugs and other chemicals may be a single occurrence or may occur almost continuously. Continual doses of a drug or continuous exposure to a chemical can have very different effects to a single dose. This may be due to a change in the metabolism of the chemical which can occur with repeated exposure to some chemicals (see below), and which may increase the detoxication and elimination of the chemical, as happens with some barbiturate drugs. Indeed some chemicals stimulate protective... 

Barbiturates and alcohol both increase the activity of (induce) the enzymes that metabolize paracetamol to the toxic product. A chronic alcohohc or someone who has been prescribed barbiturate drugs will be at greater risk when taking more than the recommended dose of paracetamol because a greater proportion of the dose will be converted into the toxic product. It would be equivalent to taking a larger dose. In the case of an alcoholic the liver may already be compromised by repeated and long-term alcohol abuse and so be more vulnerable and less able to detoxify paracetamol it may also have less protective substances like thiols. 

Poisoning has also been used as a means of official execution. The American states that use the gas chamber for executing criminals employ cyanide gas for the purpose. These days a lethal injection is the more usual method of execution. In some states in the USA and in China (which approved this method of execution only in 1997), for example, three chemicals are used. First, a barbiturate drug (sodium thiopental) is injected into a vein (this is called an intravenous injection), which rapidly causes unconsciousness (within thirty seconds). The victim is therefore unaware of what follows. Then pancuronium bromide, a muscle relaxant drug, is injected into the vein, which paralyses the muscles of the diaphragm within about three minutes and so stops respiration. Finally, a... 

Alkaloids, amides, amines, amino adds, amino phenols, antibiotics, antioxidants, barbiturates, drugs, fatty adds, indole derivatives, nucleobases, oligopeptides, optical brighteners, PAHs, peptides, pharmaceuticals, phenols, phthalates, porphyrins, preservatives, steroids, surfactants, tetracyclines... 

The development of the barbiturate drugs led to the use of depressants as sleeping pills and as treatment of anxiety symptoms and epilepsy. 

The effects of a moderate dose of a barbiturate drug resemble the effects of alcohol. 

One of the problems of barbiturate analysis is the isolation of the compound from biological material.427,428,437,449,513 Extraction is the most accepted method, but some assays take advantage of omitting the isolation and purification step. Special attention was devoted to separation and assay of particular barbiturate drugs in combination with other compounds. For example, many methods were devised for the determination of phenobarbital and hydantoin used together in anticonvulsive therapy.514 Several procedures were proposed for the determination of barbiturates along with their metabolites in body fluids.437... 

Although the chemistry of barbiturates has been explored for a very long time, these compounds still attract the attention of chemists, as exemplified by a recently published synthesis for 157 as a potential cerebral perfusion agent for tomography574 or by studies of the chemical and metabolic degradation of 158.575 However, it is the medicinal application of barbiturate drugs and... 

Some recent observations have underlined the necessity of interpreting with caution the results of experiments which have sought to modify GABA metabolism. Animals habituated to, and then withdrawn from, barbiturate drugs, develop (as do human beings) spontaneous convulsions or an increased susceptibility to audiogenic seizures . It was shown by Essig that these... 

Amytal is a barbiturate drug that blocks electron transport from NADH to coenzyme Q (Figure 15.9). Amytal blocks electron transport at the same point as the insecticide rotenone. 

Figure 8.11 Chemical structure of barbiturates, (a) General chemical structure of barbiturate drugs. Specific chemical structures for (b) barbital (c) secobarbital ...

Multiple interactions are also used with the new binding site 2,6-bis(acrylamido)pyri-dine. In this case, different barbiturate drugs, such as cyclobarbital, act as templates... 

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