Kahana L M
CMAJ. 1987 Aug 1;137(3):213-6.
Ethambutol hydrochloride has been used in the treatment of tuberculosis for 25 years. Its only important adverse effect, retrobulbar neuritis, is thought to be a minor concern with conventional dosages. The author presents four cases of serious visual impairment due to ethambutol therapy. Three of the patients were receiving a maintenance dosage of 15 mg/kg per day. The fourth patient was inadvertently given 25 mg/kg per day for 4 months. After therapy with the drug was stopped, improvement was slow, with complete recovery in two cases and only minor residual changes in a third. The patient who received the higher dosage of ethambutol suffered permanent, marked impairment. Ethambutol appears to contribute little to modern short-course antituberculous regimens that include more potent agents such as isoniazid and rifampin. In view of this and the potential for serious visual impairment, alternative antituberculous agents should be considered.
盐酸乙胺丁醇已用于治疗结核病25年。其唯一重要的不良反应——球后视神经炎，在常规剂量下被认为是一个较小的问题。作者报告了4例因乙胺丁醇治疗导致严重视力损害的病例。其中3例患者接受的维持剂量为每日15mg/kg。第4例患者无意中每日服用25mg/kg，持续了4个月。停药后，视力改善缓慢，2例完全恢复，第3例仅有轻微残留改变。接受较高剂量乙胺丁醇的患者遭受了永久性的明显损害。在包括异烟肼和利福平这类更强效药物的现代短程抗结核治疗方案中，乙胺丁醇似乎作用不大。鉴于此以及存在严重视力损害的可能性，应考虑使用其他抗结核药物。
