Barbiturates ultrashort-acting

Barbiturates. The ultrashort-acting barbiturates (see Table 1) methohexital (4), thiopental (5), and thiamylal (6) are used for induction and... 

Ultrashort-acting (eg, tiiiamylal [Surital], thiopental [Pentodial]). The ultrashort-acting barbiturates are used as anestiietics (see Chap. 35). Single doses have a duration of 20 minutes or less. 

Methohexital (Brevital) and thiopental (Ffentothal), which are ultrashort-acting barbiturates, are used for ... 

Barbiturates are usually taken orally, sometimes with alcohol to increase the intoxicating effect, or by injection. The ultrashort-acting barbiturate Pentothal produces surgical anesthesia within about one minute after intravenous administration. The onset of action of the short- and intermediateacting barbiturates taken orally for insomnia is from 10 to 60 minutes, and the effects last up to six hours. Barbiturates distribute to body fat and are found in breast milk. They may cause drowsiness, slow heartbeat, and shortness of breath in babies of nursing mothers who are taking these drugs. 

Barbiturates are classified according to their duration of action these are ultrashort acting (thiopental and methohexital), short to intermediate acting (pentobarbital, secobarbital, and amobar-bital), and long acting (phenobarbital). 

The ultrashort-acting barbiturates methohexital, thi-amylal, and thiopental produce unconsciousness within several minutes. These drugs are used for anesthesia before surgery. 

The ultrashort-acting barbiturates methohexital (Bre-vital), thiamylal (Surital), and thiopental (Pentothal) are administered as an anesthetic before surgery. The barbiturate is injected into the patient s vein to induce anesthesia. The patient then receives a longer-acting anesthetic like nitrous oxide. The drugs are used in hospital settings and are not subject to abuse, according to the DEA. 

Methohexital is an ultrashort-acting barbiturate that is widely used in dental anesthesia because of its rapid onset and short duration of action. 

Many barbituric acid derivatives have been formulated since the early 1920s. Only a few remain in regular clinical usage and only one, thiopental, is used with any regularity in equine anesthesia. Thiopental is classified as a thiobarbiturate because there is a sulfur atom on the second carbon of the barbituric acid ring. It is also classified as an ultrashort-acting barbiturate. The presence of the sulfur atom decreases the stability of the molecule and shortens the duration of anesthetic action (Branson Booth 1995). 

Ultrashort-acting Ultra-short-acting barbiturates (thiopental sodium Pentothal) are an anesthetic... 

The classification of barbiturates as ultrashort-acting, short-acting, intermediate-acting, and long-acting refers to the duration of effect and not to the elimination half-life. The duration of action is determined by the rate of distribution into brain and subsequent redistribution to other tissues. ... 

Appropriate treatment for barbiturate intoxication includes general cardiopulmonary support and measures to prevent further drug absorption and to enhance elimination. Urine alkalinization may enhance the elimination of long-acting barbiturates (e.g., phenobarbital and barbital) but has little effect on intermediate-, short-, or ultrashort-acting barbiturates. 

Thiopental sodinm belonging to the elass of ultrashort-acting barbiturates (e.g., thiopental)... 

Ultrashort-acting barbiturates are highly lipid soluble and rapidly penetrate the brain to induce anesthesia, then are quickly redistributed to other tissues. For this reason, the clinical duration of effect is much shorter than the elimination half-life for these compounds. 

Used in the induction phase of anesthesia, thiopentone is an ultrashort acting barbiturate. The drug acts within 30-45 s producing its peak concentration in the brain about 1 min after injection. Thiopentone has now been largely replaced in... 

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