Overdose barbiturate

Amphetamine (Benzedrine). Amphetamine was synthesized in 1887. It was quickly found to be a potent stimulant with effects similar to cocaine, which had been discovered over 100 years before. In the subsequent years, amphetamine found a variety of uses. It was used to treat narcolepsy, Parkinson s disease, barbiturate overdose, bed wetting (enuresis), and obesity. It was also used to counteract the sedating effects of other drugs and medications including antiseizure medications and alcohol. 

Barbiturates overdosing may occur readily. Since tolerance develops to the behavioral effects but not to the respiratory effects, increasing the dosage may result in death. Also, because of amnesia-causing effects, people forget that they took their medication and may proceed to take additional doses, which may lead to respiratory depression and death. 

Just how safe the barbiturates are is subject to much debate. For one thing, in high doses, they are lethal, the reason that for many years barbiturate overdose was a common way by which people committed suicide. In addition, the rebound produced... 

Barbiturate overdose is a factor in nearly one-third of all reported drug-related deaths in the United States. These deaths include suicides and accidental drug poisonings. Accidental deaths sometimes occur when a user takes one dose, becomes confused, and unintentionally takes additional or larger doses. In the case of barbiturates, there is a narrow margin between the amount that induces sleep and the amount that kills. 

By 1972, luding out —taking methaqualone with wine—was popular on college campuses. Excessive use of the drug leads to tolerance, dependence, and withdrawal symptoms similar to those of barbiturates. Overdose by methaqualone is more difficult to treat than barbiturate overdose, and deaths have frequently occurred. In the United States, the marketing of methaqualone pharmaceutical products was discontinued in 1984, and the drug became a Schedule I controlled substance. However, some level of occasional abuse has continued. 

Species Barbiturate Overdose Route Chloralhydrate Overdose Route Ketamine Overdose Route... 

Barbiturate overdose may be treated with gastric lavage and oral administration of activated charcoal. Supportive therapy of cardiovascular, respiratory, and renal function also should be provided. Coadministration of alcohol and barbiturates may increase the sedative effect of chloral hydrate. Long-term use of barbiturates leads to dependence. Sudden discontinuation of an antipsychotic drug may cause withdrawal symptoms such as nausea, vomiting, anorexia, diarrhea, rhinorrhea, sweating, insomnia, restlessness, and vertigo.151... 

The effect of urinary pH on drug ionization also has toxicological implications. For example, in cases of phenobarbital (a weak acid barbiturate) overdose the urine can be alkalinized (the pH elevated) by administering sodium bicarbonate to the patient. The resultant increase in pH shifts the dissociation equilibrium for this weak acid to the right, producing an increase in the proportion of the ionized form, less reabsorption in the kidneys, and more rapid elimination. Conversely, acidifying the urine with ammonium chloride will increase the excretion rate of drugs that are weak bases since they will be more protonated (ionized) and less reabsorbed (more polar, less lipophilic). 

Ethchlorvynol, USP. Ethchlurvynol. l-chloro-.A-cthyl-l-penten-4-yn-.A-ol (Placidyl). is a sedative-hypnotic with a rapid on.sct and short duration of action. Metabolism, probably involving the hydroxyl group, accounts for about 90% of a dose. Acute overdo.se shares several features with barbiturate overdose. 

Methyprylon produces depression of the CNS and decreases rapid eye movement sleep in a fashion similar to the barbiturates. Overdoses may also result in cardiovascular depression. 

Methods are avahable for detecting barbiturate overdose and abuse. To detect overdose, semiquantitative immunoassays suitable for detection of barbiturates in serum are avaUable and useful for this purpose. Capillary GC is also useful for this purpose, and a capillary GC procedure is described in the Chapter 34 Appendix that is formd on this book s accom-... 

Capillary Gas Chromatography. To detect barbiturate overdose, a serum sample can be analyzed for several barbiturates using the capillary GC technique described in the Chapter 34 Appendix that is found on this book s accompanying Evolve site (http //evolve.elsevier.com/Tietz/text-book/). In this method, aprobarbital is first added to an aliquot of the sample as an internal standard. Barbiturates in the aliquot are then extracted twice with diethyl ether, and the ether is dehydrated with solid sodium sulfate and then evaporated to dryness. The residue is dissolved in 50)uL of ethyl acetate, and an aliquot is injected into the gas chromatograph. 

Henderson-Hasselbalch equation, Chapter 1). It may result from central depression of respiration (e.g., narcotic or barbiturate overdose, trauma, infection, cerebrovascular accident) or from pulmonary disease (e.g., asthma, obstructive lung disease, infection). Increased [H+] is in part buffered by cellular uptake of H+ with corresponding loss of intracellular K" ". In acute hypercapnia, the primary compensatory mechanism is tissue buffering. In chronic hypercapnia, the kidneys respond to elevated plasma Pcoj increasing the amount of HCO formed by carbonic an-hydrase in the tubules and by excreting more H+. 

IV. Diagnosis is usually based on a history of ingestion and should be suspected in any epileptic patient with stupor or coma. Although skin bullae are sometimes seen with barbiturate overdose, these are not specific for barbiturates. Other causes of coma should also be considered (see p 19). 

Prajapati P, Sheikh MI, Brahmbhatt J. Barbiturate overdose a case report. J Indian Med Assoc 2009 107(12) 897-8. 

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