Pharmacokinetic Studies of Rifampicin in the Elderly

To better define the pharmacokinetics and serum bactericidal activity (SBA) of ciprofloxacin and other antimicrobial agents in the elderly, six healthy elderly (>65 years) volunteers with normal renal function were given ciprofloxacin alone orally, ciprofloxacin plus rifampin orally, ciprofloxacin plus clindamycin orally, rifampin alone orally (three volunteers), and, for comparison of SBA against gram-positive cocci, vancomycin intravenously. Mean peak ciprofloxacin concentrations and other pharmacokinetic parameters were not altered significantly by coadministration of either rifampin or clindamycin. Ciprofloxacin had somewhat greater SBA against the oxacillin-susceptible and oxacillin-resistant Staphylococcus aureus strains tested than did vancomycin, but rifampin was by far the most active single agent tested. The SBA of rifampin against S. aureus was modestly antagonized during combination therapy with ciprofloxacin, but substantial SBA still was present. The ciprofloxacin SBA against S. aureus was completely antagonized by clindamycin if the strains were susceptible to the latter agent. Ciprofloxacin had modest SBA against group A streptococci and no SBA against the three pneumococcal strains tested. All of the regimens had poor to absent SBA against Enterococcus faecalis. By contrast, ciprofloxacin had excellent SBA against Escherichia coli and Klebsiella pneumoniae and moderate SBA against Pseudomonas aeruginosa. Combination therapy with rifampin or clindamycin in general enhanced the SBA against the nonenterococcal streptococci and had no effect on the SBA against the gram-negative bacilli.

Section: Discussioncontrasting

confidence: 99%

Section: Discussionmentioning

confidence: 96%

mentioning

confidence: 88%

See 1 more Smart Citation

Crossover assessment of serum bactericidal activity and pharmacokinetics of ciprofloxacin alone and in combination in healthy elderly volunteers

Weinstein¹,

Deeter²,

Swanson³

et al. 1991

“…Likewise, no significant differences in rifampin pharmacokinetic parameters occurred, compared with historical controls (2).…”

Section: Discussionmentioning

confidence: 80%

Multiple-dose pharmacokinetics of concurrent oral ciprofloxacin and rifampin therapy in elderly patients

Chandler

Toler

Rapp

et al. 1990

The purpose of this clinical study was to investigate the influence of concomitant drug therapy with ciprofloxacin and rifampin on the individual pharmacokinetic profile of each agent in elderly patients. Twelve nursing home patients (age, 74 7 years), colonized with methiiillin-resistant Staphylococcus aureus, were randomized to receive 14-day therapy with oral ciprofloxacin (750 mg every 12 h) (group A; n = 6) or ciprofloxacin (750 mg every 12 h) and oral rifampin (300 mg every 12 h) (group B; n = 6). Serial blood samples were obtained from 0 to 12 h following ciprofloxacin doses 1 and 13 and from 0 to 36 h after the last ciprofloxacin dose. No significant differences (P > 0.05) were found between or within groups in any pharmacokinetic parameter. The mean ciprofloxacin oral clearance values were 0.35 ± 0.06, 0.41 ± 0.15, and 0.38 ± 0.11 liter/h per kg for doses 1, 13, and 28, respectively, in group A patients. The mean oral clearance values in group B patients for the respective doses were 0.53 ± 0.36, 0.32 ± 0.13, and 0.36 ± 0.17 liter/h per kg. Likewise, no significant differences (P > 0.05) in rifampin pharmacokinetic parameters were found when compared with historical controls. These data suggest that ciprofloxacin and rifampin may be given concomitantly in standard clinical dosing regimens. The combination results in therapeutic levels of both drugs and appears to be safe for adminiration to elderly nursing home patients.Colonization and infection with methicillin-resistant

“…Older patients tend to accumulate drugs for longer periods of time, and some might require dosage adjustments. Studies of the pharmacokinetics of RMP and rifapentine in the elderly population, however, do not suggest the need for any dose modifications (15,16).…”

Section: Discussionmentioning

confidence: 99%

Factors Influencing Tuberculosis Treatment Outcome in Adult Patients Treated with Thrice-Weekly Regimens in India

Ramachandran

Kupparam

Chandrasekaran

et al. 2017

The Indian Revised National Tuberculosis (TB) Control Programme uses thrice-weekly treatment with standard drug dosages. The role of plasma drug levels and other factors in determining TB treatment outcomes is not well understood. We aimed to determine the factors influencing the concentrations of rifampin (RMP), isoniazid (INH), and pyrazinamide (PZA) at 2 h postdosing in adult TB patients and to study the factors impacting TB treatment outcome. We recruited 1,912 adult TB patients (newly treated and retreated patients) with pulmonary/extrapulmonary TB receiving antitubercular treatment (ATT) in the RNTCP in Chennai, India. At steady state, the concentrations of RMP, INH, and PZA were determined at 2 h postdosing after supervised drug administration. A total of 1,648 patients had a favorable outcome, while 264 (14%) had an unfavorable outcome. A total of 91%, 16%, and 17% of the patients had suboptimal concentrations of RMP (Ͻ8 g/ml), INH (Ͻ3 g/ml), and PZA (Ͻ20 g/ml), respectively. Factors associated with treatment outcome were low RMP concentrations (adjusted odds ratio [aOR], 0.94; 95% confidence interval [CI], 0.89 to 0.99; P ϭ 0.036), category II ATT (aOR, 2.39; 95% CI, 1.56 to 3.65; P Ͻ 0.001), low body weight (aOR, 0.96; 95% CI, 0.94 to 0.98; P Ͻ 0.001), alcohol use (aOR, 2.17; 95% CI, 1.42 to 3.31; P Ͻ 0.001), male gender (aOR, 1.92; 95% CI, 1.02 to 3.62; P ϭ 0.043), and baseline INH resistance (aOR, 5.74; 95% CI, 3.12 to 10.59; P Ͻ 0.001), which significantly increased the likelihood of an unfavorable outcome in multivariate logistic regression analysis. Further studies are needed to optimize anti-TB drug dosages and improve cure rates. Drug susceptibility testing at the baseline and attention to undernutrition and alcohol dependence are other important interventions.