The liver occupies a key position in the metabolism of drugs including antibiotics. Its function is to change these largely insoluable agents to water soluable ones for biliary and urinary excretion. Many drugs can injure the liver, but most drugs that produce hepatic damage appear to have as sensitizing agents (hypersensitivity) rather than hepatotoxins(toxic). Damage to the liver by drugs is often referred to as either "predictable" or "non-predictable." In the former {toxic), the liver injury is a normal consequence of the administration of drugs and the severity of this damage is often dose-related. In non-predictable drug injury (hypersensitivity), a harmful effect on liver structure and function is seen in only a small percentage of patients treated with that agent and not dose-related. The examples of antibiotics which cause predictable hepatic damage are tetracyclines and novobiocin, and on the other hand, those which show unpredictable liver damage are penicillin, erythromycin and chioramphenicol.
Prompt withdrawal of the offending agent(s) is of prime importance in the management of antibiotics-induced hepatic damage, since this alone may abort the reaction and prevent serious injury to the liver. Most reactions subside spontaneously following withdrwal of the offending antibiotics, and require nothing but supportive measures.
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