Douglas-Hall Petrina, Dzahini Olubanke, Gaughran Fiona, Bile Ahmed, Taylor David
Clinical Pharmacist, South London and Maudsley NHS Foundation Trust, Pharmacy Department, Maudsley Hospital, Denmark Hill, London SE5 8AZ, UK.
Research Pharmacist, South London and Maudsley NHS Foundation Trust, Pharmacy Department, Maudsley Hospital, London, UK.
Ther Adv Psychopharmacol. 2017 Jan;7(1):17-24. doi: 10.1177/2045125316672573. Epub 2016 Oct 13.
The objectives of this study were to investigate the dose of lamotrigine when prescribed with an enzyme inhibitor or enzyme inducer in patients discharged from a mental health trust and to determine the corresponding lamotrigine plasma concentrations and the factors that may affect these.
All patients discharged on lamotrigine between October 2007 and September 2012 were identified using the pharmacy dispensing database. We recorded demographic details, lamotrigine dose and plasma levels and coprescribed medication.
During the designated period, 187 patients were discharged on lamotrigine of whom 117 had their plasma levels recorded. The mean lamotrigine daily dose was 226.1 mg (range 12.5-800 mg) and the mean plasma level 5.9 mg/l (range 0.8-18.1 mg/l). Gender, ethnicity, diagnosis and smoking status had no significant effect on dose or plasma levels. Patients taking an enzyme-inducing drug ( = 6) had significantly lower plasma levels [mean (SD) 3.40 (1.54) mg/l] than those not taking enzyme inducers [ = 111; 6.03 (3.13) mg/l; = 0.043]. Patients taking an enzyme-inhibiting drug ( = 23) had significantly higher levels [7.47 (3.99) mg/l] than those not taking an inhibitor [ = 94; 5.52 (2.75) mg/l; = 0.035]. No significant difference was found between the doses of lamotrigine in patients taking an enzyme inhibitor and those not taking one ( = 0.376). No significant difference was found between the doses of lamotrigine in patients taking an enzyme-inducing drug and those not taking any ( = 0.574).
Current dosing recommendations indicate that lamotrigine doses should be halved in individuals taking enzyme inhibitors and doubled in those on enzyme inducers. In our survey these recommendations were rarely followed with the consequence that patients received too high or too low a dose of lamotrigine, respectively.
本研究的目的是调查在精神卫生信托机构出院的患者中，与酶抑制剂或酶诱导剂联用时拉莫三嗪的剂量，并确定相应的拉莫三嗪血浆浓度以及可能影响这些浓度的因素。
利用药房配药数据库识别出2007年10月至2012年9月期间所有出院时服用拉莫三嗪的患者。我们记录了人口统计学细节、拉莫三嗪剂量、血浆水平和联合开具的药物。
在指定期间，187例患者出院时服用拉莫三嗪，其中117例记录了血浆水平。拉莫三嗪的日均剂量为226.1毫克（范围12.5 - 800毫克），平均血浆水平为5.9毫克/升（范围0.8 - 18.1毫克/升）。性别、种族、诊断和吸烟状况对剂量或血浆水平无显著影响。服用酶诱导药物的患者（n = 6）血浆水平显著低于未服用酶诱导剂的患者[n = 111；6.03（3.13）毫克/升；P = 0.043]，为3.40（1.54）毫克/升。服用酶抑制药物的患者（n = 23）血浆水平显著高于未服用抑制剂的患者[n = 94；5.52（2.75）毫克/升；P = 0.035]，为7.47（3.99）毫克/升。服用酶抑制剂的患者与未服用酶抑制剂的患者拉莫三嗪剂量之间未发现显著差异（P = 0.376）。服用酶诱导药物的患者与未服用任何此类药物的患者拉莫三嗪剂量之间未发现显著差异（P = 0.574）。
目前的给药建议表明，服用酶抑制剂的个体拉莫三嗪剂量应减半，服用酶诱导剂的个体剂量应加倍。在我们的调查中，这些建议很少被遵循，结果患者分别接受了过高或过低剂量的拉莫三嗪。
