头孢三嗪新治疗方案的评价

CEFTRIAXONE THE EVALUATION OF REGIMEN ON ITS PHARMACOKINETICS

本文根据正常人的药代动力学参数运用微电脑特定程序进行计算,选择出一种合理的治疗方案,此方案用于20例中度感染的患者进行治疗,结果认为此方案是可行的、满意的.

Ceftriaxone, a newsemisynthetic beta-lactam antibiotic withexcellent activity of a broad-spectrumagainst aerobic gram-positive and - nega-tive bacteria, due to its characteristic oflong half-life (6-8 hr), can be administeredless frequently than other conventionalcephalosporins. There are some differentdosage regimens have been adoptedclinically; the dosage ranges are variedfrom 0.5-2 grams b.i.d. If the dose is overthe requirement for therapy, not only mayits toxicity to patients be induced, but alsomeans the waste of drug and money. If thedose is less than therapeutic necessity, theclinical therapy might be no effect. So whatis the best regimen universally accepted bythe most clinicians nowadays? Based upon our previous studies ofpharmacokinetics in normal volunteers, arational regimen on ceftriaxone was pro-posed which was selected by computer with a proper program. The requirement ofregimen were that, the peak and troughplasma levels of ceftriaxone should beachieved to >200mg/ l and 50 mg/ l,respectively after 1 gram of i.v. bolus injec-tion, or>100 mg / l and 30mg/ l,respectively after 0.5 gram or ceftriaxonegiven intravenously for the purpose ofmaintaining the therapeutic concentrationshigh enough in blood. The experimental re-sults of this regimen had demonstrated thatthe drug levels in plasma in healthy volun-teers were in agreement with the resultscalculated by computer. The proposed clin-ical regimen was as follows: ceftriaxonewas dissolved in 20-ml normal saline andinjected intravenously over a period of 5minutes at a dose of 1 gram every 12 hr fortwo days, then 0.5 g of the drug adminis-tered with same manner for five consistentdays in a total duration of seven days. Twenty patients with diferent moder-ate infections, namely, genito-urinary tractinfection, respiratory tract infection, biliarytract infection and soft tissue infection,were treated with ceftriaxone accordingly.The pathogens isolated clinically consistedof H influenzae, E coli, Klcbsiclla sp., Psacruginosa, S aureus and Streptococcussp.. All patients with exception or one hadgood clinical responses to the one-weektreatment. The peak and trough drug con-centrations in blood at day 1 and day 5were 271 .1 to 380.9 and 18.1 to 58.6 mg / l,at day 1 respectively; and 138.7 to 190.4and 21.1 to 37.2 mg/ l, at day 5respectively. These drug levels were similarto the results of healthy volunteers and farhigher than that of the MIC_(90) valuesagainst most clinical isolates. Some pa-tients had mild diarrhoca during thetherapy but no attempt was adopted todiscontinue the treatment. No other ad-verse drug effects were significantly ob-served. Our study indicated that this regimenis rational and effective definitely for treat-ing moderate infections, but the result oftreating severe infections needs further clin-ical investigations.