Neuvonen P J, Olkkola K T
Department of Clinical Pharmacology, University of Helsinki.
Med Toxicol Adverse Drug Exp. 1988 Jan-Dec;3(1):33-58. doi: 10.1007/BF03259930.
Activated charcoal has an ability to adsorb a wide variety of substances. This property can be applied to prevent the gastrointestinal absorption of various drugs and toxins and to increase their elimination, even after systemic absorption. Single doses of oral activated charcoal effectively prevent the gastrointestinal absorption of most drugs and toxins present in the stomach at the time of charcoal administration. Known exceptions are alcohols, cyanide, and metals such as iron and lithium. In general, activated charcoal is more effective than gastric emptying. However, if the amount of drug or poison ingested is very large or if its affinity to charcoal is poor, the adsorption capacity of activated charcoal can be saturated. In such cases properly performed gastric emptying is likely to be more effective than charcoal alone. Repeated dosing with oral activated charcoal enhances the elimination of many toxicologically significant agents, e.g. aspirin, carbamazepine, dapsone, dextropropoxyphene, cardiac glycosides, meprobamate, phenobarbitone, phenytoin and theophylline. It also accelerates the elimination of many industrial and environmental intoxicants. In acute intoxications 50 to 100g activated charcoal should be administered to adult patients (to children, about 1 g/kg) as soon as possible. The exceptions are patients poisoned with caustic alkalis or acids which will immediately cause local tissue damages. To avoid delays in charcoal administration, activated charcoal should be a part of first-aid kits both at home and at work. The 'blind' administration of charcoal neither prevents later gastric emptying nor does it cause serious adverse effects provided that pulmonary aspiration in obtunded patients is prevented. In severe acute poisonings oral activated charcoal should be administered repeatedly, e.g. 20 to 50g at intervals of 4 to 6 hours, until recovery or until plasma drug concentrations have fallen to non-toxic levels. In addition to increasing the elimination of many drugs and toxins even after their systemic absorption, repeated doses of charcoal also reduce the risk of desorbing from the charcoal-toxin complex as the complex passes through the gastrointestinal tract. Charcoal will not increase the elimination of all substances taken. However, as the drug history in acute intoxications is often unreliable, repeated doses of oral activated charcoal in severe intoxications seem to be justified unless the toxicological laboratory has identified the causative agent as not being prone to adsorption by charcoal. The role of repeated doses of oral activated charcoal in chronic intoxication has not been clearly defined.(ABSTRACT TRUNCATED AT 400 WORDS)
活性炭具有吸附多种物质的能力。这一特性可用于防止各种药物和毒素的胃肠道吸收，并增加它们的清除，即使在全身吸收之后。单次口服活性炭能有效防止在服用活性炭时胃内存在的大多数药物和毒素的胃肠道吸收。已知的例外情况是酒精、氰化物以及铁和锂等金属。一般来说，活性炭比胃排空更有效。然而，如果摄入的药物或毒物量非常大，或者其与活性炭的亲和力很差，活性炭的吸附能力可能会饱和。在这种情况下，正确进行的胃排空可能比单独使用活性炭更有效。多次口服活性炭可增强许多具有毒理学意义的物质的清除，例如阿司匹林、卡马西平、氨苯砜、右丙氧芬、强心苷、甲丙氨酯、苯巴比妥、苯妥英和茶碱。它还能加速许多工业和环境毒物的清除。在急性中毒时，应尽快给成年患者服用50至100克活性炭（儿童约为1克/千克）。苛性碱或酸中毒的患者除外，因为这些物质会立即造成局部组织损伤。为避免服用活性炭的延迟，活性炭应成为家庭和工作场所急救箱的一部分。“盲目”服用活性炭既不会妨碍后续的胃排空，也不会造成严重不良反应，前提是防止昏迷患者发生肺误吸。在严重急性中毒时，应多次口服活性炭，例如每隔4至6小时服用20至50克，直至康复或血浆药物浓度降至无毒水平。除了即使在药物和毒素全身吸收后仍能增加其清除外，多次服用活性炭还可降低活性炭 - 毒素复合物在通过胃肠道时从复合物上解吸的风险。活性炭不会增加所有摄入物质的清除。然而，由于急性中毒时的用药史往往不可靠，在严重中毒时多次口服活性炭似乎是合理的，除非毒理学实验室已确定致病剂不易被活性炭吸附。多次口服活性炭在慢性中毒中的作用尚未明确界定。（摘要截取自400字）
