Fluconazole dosing in continuous veno-venous haemofiltration (CVVHF): need for a high daily dose of 800 mg

To cover intermediate sensitive Candida glabrata in ICU patients,fluconazole plasma peak levels at least in the range of 16–32µg/ml appear necessary for treatment. Previous studiesdid not reach these fluconazole levels under continuous veno-venoushaemofiltration (CVVHF) with dosages of 200–600 mg fluconzoledaily. In the present study, nine patients simultaneously requiringCVVHF for treatment of acute oligoanuric renal failure and antimycotictherapy of Candida septicemia received fluconazole 800 mg/day.Fluconazole plasma levels were determined to evaluate whetherthis dosage is adequate to reach the advised fluconazole levels.Patients were dialysed on two consecutive days with an ultrafiltrationrate (UF) of 1000 ml/h or 2000 ml/h, respectively, in a randomizedorder. The predilution was 800 ml/h and 1800 ml/h, respectively.The treatment was tolerated without adverse effects. All patientsreached plasma fluconazole concentrations between 16 and 32µg/ml, remaining in this range for a minimum of 1 up to24 h with a mean of 9.6 h and a UF rate of 2000 ml/h, and 15.7h with a UF rate of 1000 ml/h. So far, there are no in vivodata on the fluconazole plasma concentrations required for effectivetreatment. However, our data demonstrate, that at least thefluconazole concentrations desirable on the basis of in vitrosusceptibility testing can be reached in critically ill patientson CVVHF in an ICU setting. However, in these patients, 800mg fluconazole/day are necessary to achieve fungicidal drugconcentrations.     

The effect of fluconazole and ketoconazole on the metabolism of sulphamethoxazole

1 Cytochrome P450-mediated bioactivation of sulphamethoxazole to a hydroxylamine has been implicated in the hypersensitivity reactions associated with co-trimoxazole administration. Inhibiting the formation of the hydroxylamine may be one method of preventing the high frequency of toxicity which is observed in HIV-infected patients. Therefore, in this study, we have investigated the ability of fluconazole and ketoconazole, known cytochrome P450 inhibitors, to inhibit the formation of sulphamethoxazole hydroxylamine.
2 Ten healthy male volunteers were given co-trimoxazole (800  mg sulphamethoxazole and 160  mg trimethoprim) alone or 1  h after either fluconazole (150  mg) or ketoconazole (200  mg) in a randomized fashion with a washout period of at least 1 week between each phase. Urine was collected for 24  h, and sulphamethoxazole and its metabolites were quantified by electrospray LC-MS.
3 Ketoconazole had no effect on the urinary recovery of sulphamethoxazole or any of its metabolites. In contrast, fluconazole significantly ( P <0.001) inhibited the formation of sulphamethoxazole hydroxylamine by 50.0±15.1%. Fluconazole also inhibited the oxidation of sulphamethoxazole to the 5-methylhydroxy and 5-methylhydroxy acetate metabolites by 69.9±15.8% and 64.0±12.0%, respectively, but had no effect on the amount of sulphamethoxazole, N₄-acetyl sulphamethoxazole, or sulphamethoxazole N₁-glucuronide excreted in urine.
4 The potential clinical benefit of using fluconazole to prevent hypersensitivity to co-trimoxazole in patients with AIDS needs to be assessed in a prospective study using both metabolite formation and the clinical occurrence of adverse reactions as end-points.     

Synovial fluid levels of fluconazole in a patient with Candida parapsilosis prosthetic joint infection who had an excellent clinical response

A 73-year-old woman presenting with persistent swelling of the right knee 30 months after total joint arthroplasty was found to have a Candida parapsilosis infection. Treatment with fluconazole resulted in full recovery.     

The efficacy of fluconazole in treating prosthetic valve endocarditis caused byCandida glabrata: Report of a case

A case of active prosthetic valve infective endocarditis (PVE) due toCandida glabrata was successfully treated by the systemic administration of fluconazole. A 66-year-old Japanese man with infective endocarditis of unknown etiology underwent aortic and mitral valve replacement to treat severe aortic and mitral regurgitation associated with multiple organ failure. Postsurgical cultures of arterial blood were repeatedly positive forC. glabrata, and therefore fluconazole was administered either intravenously or orally at a dose of 400 mg/day for 46 days. During that time the signs of inflammation including fever such as an elevated white blood cell count and the presence of C-reactive protein (CRP) all improved while the blood cultures became negative. Fluconazole is thus considered to be effective in treating PVE caused byC. glabrata. When administering this treatment, it is also important to monitor the patient's renal and liver function.     

氟康唑胶囊的人体生物等效性研究

目的评价广州光华药业股份有限公司研制的氟康唑胶囊(受试制剂)与大连辉瑞制药有限公司生产的氟康唑胶囊(参比制剂)的生物等效性。方法20名健康志愿者随机交叉、单剂量口服氟康唑胶囊被试制剂与参比制剂各150 mg,用高效液相色谱法测定血浆中氟康唑浓度。用3P97药动学软件进行参数计算及生物等效性评价。结果受试制剂和参比制剂的主要药动学参数如下:tmax分别为(1.0±0.7)h和(1.7±0.8)h,Cmax分别为(4.0±1.2)mg.L-1和(3.6±1.3)mg.L-1,AUC0-t分别为(132.4±26.5)mg.h.L-1和(138.4±30.8)mg.h.L-1,AUC0-∞分别为(143.7±26.1)mg.h.L-1和(150.2±33.1)mg.h.L-1。氟康唑胶囊受试制剂的相对生物利用度为(97.9±18.3)%。结论对tmax及经对数转换后的Cmax、AUC0-t进行统计分析、方差分析后进行双单侧t检验及90%可信限判断,两制剂具有生物等效性。     

固相萃取-高效液相色谱法测定人血浆中氟康唑浓度及其药动学研究

目的:建立测定人体血浆中氟康唑浓度的高效液相色谱法,并对供试制剂与参比制剂的生物等效性进行评价.方法:血样处理采用固相萃取方法,萃取小柱用甲醇活化后加入血浆1 mL,过柱后用含20%甲醇的水溶液1.0 mL洗涤,再用0.2 mL甲醇洗脱收集,取20 μL进样.色谱柱为C18柱 (150 mm×4.6 mm,5 μm),流动相为0.01 mol·L-1磷酸二氢钾(用磷酸调pH值为5.0)-乙腈(75:25);流速为1.0 mL·min-1,检测波长为267 nm.人体药动学试验采用双周期交叉设计方案,将18例志愿受试者随机分为2组,分别口服氟康唑供试胶囊和参比胶囊150 mg.结果:本方法线性范围为0.1～6.4 mg·L-1,r=0.999 9,最低检测浓度为0.1 mg·L-1,方法回收率为95.7%～108.0%,日内、日间RSD均小于15%,供试制剂与参比制剂主要药动学参数经统计学分析差异无显著性,供试制剂的相对生物利用度为(105.7±12.6)%.结论:本方法灵敏度高,特异性强,重现性好,供试制剂与参比制剂具有生物等效性.     

体外诱导白念珠菌对氟康唑耐药性的研究

目的:建立白念珠菌耐氟康唑模型,研究白念珠菌耐药前后相关生物学特性变化。方法:体外用氟康唑诱导敏感白念珠菌SC5314和y01.09成为耐药子代SC5314R和y01.09R,利用微量液基稀释法和小鼠体内实验确定耐药表型,通过生长动力学、菌丝和生物膜形成实验观察生物学特性变化。结果:氟康唑对耐药子代SC5314R和y01.09R的MIC80分别为>128μg/mL,64μg/mL。无药培养35代后,MIC80分别为>128μg/mL,16μg/mL。有/无氟康唑环境下,敏感母本和耐药子代倍增时间无显著差异。氟康唑作用下,SC5314和y01.09菌丝形成受到抑制,SC5314R和y01.09R仍有菌丝形成;SC5314R和y01.09R可以形成牢固生物膜,SC5314和y01.09形成松散生物膜。结论:本实验成功诱导对氟康唑产生高度耐药的白念珠菌菌株,其耐药性通过体内外实验获得证实。     

Fabrication and design of transdermal fluconazole spray

The objective of the present study was to formulate fluconazole transdermal spray for obtaining modified drug transport using eutectic mixture, ethyl cellulose, polyethylene oxide and alcohol. The formulated products were characterized. The selection of the optimized batch was done considering the results of drug transport in the first hour, the time required for 90% drug transport, viscosity and spray angle of the formulations. The inclusion of eutectic mixture, consisting of equal parts of camphor and menthol, showed improved drug transport through rat skin. The optimized batch exhibited larger mean zone of inhibition (antifungal activity), efficient in vivo activity and short term stability.