Department of Pediatrics, Children's Mercy Hospitals and Clinics, University of Missouri School of Medicine, Kansas City, MO 64108, USA.
Clin Toxicol (Phila). 2011 Jun;49(5):434-5. doi: 10.3109/15563650.2011.586639.
Major symptoms can occur from tetrahydrozoline (THZ) overdoses in young children, requiring intensive care management. We report three cases that presented with CNS depression and cardiovascular effects where serum concentrations were performed.
Case 1 ingested an unknown amount of eye drops containing THZ, resulting in altered mental status, bradycardia, hypothermia, and hypotension. Cases 2 and 3 ingested 7.5 mL of eye drops containing THZ. Case 2 presented to the emergency department (ED) without symptoms but became lethargic and bradycardic 90 min after ingestion. By contrast, Case 3 became lethargic 15 min after ingestion and required intubation on arrival to the ED. All children were admitted to ICU for observation and improved within 24 h of ingestion. Urine obtained for drug screening was positive for THZ. Blood was obtained to assess level using gas-chromatography mass-spectrometry (GC-MS).
Case 1 had plasma levels of 51.4 and 23.6 ng/mL at 7 and 12 h, respectively, after ingestion, revealing a half-life of 4.4 h. Numerous case reports have been published documenting the dangers of ingesting these topical over-the-counter (OTC) products. However, human PK data are not available to help in our understanding of THZ toxicokinetics and disposition in humans after ingestion.
We report three pediatric cases after ingestion of THZ where plasma concentrations were obtained with a calculated half-life of 4.4 h in one case.
小儿四氢唑啉（THZ）过量可出现严重症状，需重症监护管理。我们报告三例出现中枢神经系统抑制和心血管效应的病例，检测了血清浓度。
例 1 摄入未知剂量的含 THZ 的眼药水，出现精神状态改变、心动过缓、低体温和低血压。例 2 和例 3 分别摄入 7.5 毫升含 THZ 的眼药水。例 2 摄入后无症状，但在 90 分钟时出现嗜睡和心动过缓。相比之下，例 3 在摄入后 15 分钟出现嗜睡，并在到达 ED 时需要插管。所有患儿均入住 ICU 观察，摄入后 24 小时内均有改善。尿液药物筛查阳性，THZ。为评估水平采集血液，使用气相色谱-质谱法（GC-MS）。
例 1 在摄入后 7 小时和 12 小时的血浆水平分别为 51.4 和 23.6 ng/mL，半衰期为 4.4 小时。已有大量病例报告记录了摄入这些局部非处方（OTC）产品的危险。然而，目前尚无人体药代动力学数据可帮助我们了解 THZ 摄入后在人体内的毒代动力学和处置。
我们报告了三例小儿摄入 THZ 后的病例，其中一例计算出半衰期为 4.4 小时。
