Ciprofloxacin. A review of its pharmacological profile and therapeutic use in the elderly

Monolayer Adsorption of Ciprofloxacin on Magnetic Inulin/Mg-Zn-Al Layered Double Hydroxide: Advanced Interpretation of the Adsorption Process

In this study, magnetic inulin/Mg-Zn-Al layered double hydroxide (MILDH) was synthesized for the adsorption of ciprofloxacin. The application of various analytical techniques confirmed the successful formation of MILDH. For the optimization of controllable factors, Taguchi design was applied and optimum values were obtained as equilibrium time─100 min, adsorbent dose─20 mg, and ciprofloxacin concentration─30 mg/L. The highest capacity of the material was recorded as 196.19 mg/g at 298 K. Langmuir model (R2 = 0.9669-0.9832) fitted best as compared to the Freundlich model (R2 = 0.9588-0.9657), concluded the monolayer adsorption of ciprofloxacin on MILDH. Statistical physics model M 2 was found to fit best to measured data (R2 = 0.9982-0.9989), indicating that the binding of ciprofloxacin took place on two types of receptor sites (n1 and n2). The multidocking mechanism with horizontal position was suggested on the first receptor site (n1 < 1), while multimolecular adsorption of ciprofloxacin lying vertically on the second receptor site (n2 > 1) at all temperatures. The adsorption energies (E1 = 22.79-27.20 kJ/mol; E2 = 18.00-19.46 kJ/mol) illustrated that the adsorption of ciprofloxacin onto MILDH occurred through physical forces. Best fitting of the fractal-like pseudo-first-order kinetic model (R2 = 0.9982-0.9992) indicated that the adsorption of ciprofloxacin happened on the MILDH surface having different energies. X-ray photoelectron spectroscopy analysis further confirmed the adsorption mechanism of ciprofloxacin onto MILDH.

Primary lymphoedema

Lymphoedema is the swelling of one or several parts of the body owing to lymph accumulation in the extracellular space. It is often chronic, worsens if untreated, predisposes to infections and causes an important reduction in quality of life. Primary lymphoedema (PLE) is thought to result from abnormal development and/or functioning of the lymphatic system, can present in isolation or as part of a syndrome, and can be present at birth or develop later in life. Mutations in numerous genes involved in the initial formation of lymphatic vessels (including valves) as well as in the growth and expansion of the lymphatic system and associated pathways have been identified in syndromic and non-syndromic forms of PLE. Thus, the current hypothesis is that most cases of PLE have a genetic origin, although a causative mutation is identified in only about one-third of affected individuals. Diagnosis relies on clinical presentation, imaging of the structure and functionality of the lymphatics, and in genetic analyses. Management aims at reducing or preventing swelling by compression therapy (with manual drainage, exercise and compressive garments) and, in carefully selected cases, by various surgical techniques. Individuals with PLE often have a reduced quality of life owing to the psychosocial and lifelong management burden associated with their chronic condition. Improved understanding of the underlying genetic origins of PLE will translate into more accurate diagnosis and prognosis and personalized treatment.

Liquid crystal delivery of ciprofloxacin to treat infections of the female reproductive tract

Infections of the female reproductive tract are a major cause of morbidity and mortality in humans, requiring significant investment to sustain treatment and representing a major challenge to health. The increasing prevalence of bacterial resistance, and an almost complete absence of new antibiotic therapies for the past five decades, mean there is a desperate need for novel approaches to the treatment of bacterial infections. Within the present study, we demonstrate the effective ex vivo treatment of bacterial infection of the female reproductive tract using a controlled-release, liquid crystal-based platform. Liquid crystal encapsulation of ciprofloxacin significantly enhanced its bactericidal efficacy and reduced cell toxicity. Liquid crystal structures are low-cost, simple to manufacture and provide a sustained-release profile of encapsulated ciprofloxacin. Treatment of Escherichia coli infected reproductive tract epithelial cells and whole organ cultures with liquid crystal encapsulated ciprofloxacin proved to be an effective strategy for reducing bacterial load and reproductive tract inflammatory responses to infection. These data suggest that such an approach could provide an efficacious treatment modality for enhancing the effectiveness of current antibiotic therapies.

Antibacterial Derivatives of Ciprofloxacin to Inhibit Growth of Necrotizing Fasciitis Associated Penicillin Resistant Escherichia coli

Escherichia coli (E. coli) is associated with necrotizing fasciitis (type I) and can induce enough damage to tissue causing hypoxia. Three ester derivatives of the broad-spectrum antibiotic ciprofloxacin were placed into bacteria culture simultaneously with the parent ciprofloxacin (drug 1) to ascertain the level of antibacterial activity. The n-propyl (drug 2), n-pentyl (drug 3), and n-octyl (drug 4) esters of ciprofloxacin were synthesized under mixed phase conditions and by microwave excitation. The formation of ester derivatives of ciprofloxacin modified important molecular properties such as Log P and polar surface area which improves tissue penetration, yet preserved strong antibacterial activity. The Log P values for drugs 1, 2, 3, and 4 became -0.701, 0.437, 1.50, and 3.02, respectively. The polar surface areas for drugs 1, 2, 3, and 4 were determined to be 74.6 Angstroms(2), 63.6 Angstroms(2), 63.6 Angstroms(2), and 63.6 Angstroms(2), respectively. These values of Log P and polar surface area improved tissue penetration, as indicated by the determination of dermal permeability coefficient (K p ) and subsequently into the superficial fascial layer. All drugs induced greater than 60% bacterial cell death at concentrations less than 1.0 micrograms/milliliter. The ester derivatives of ciprofloxacin showed strong antibacterial activity toward penicillin resistant E. coli.

Effect of total and partial nephrectomy on the elimination of ciprofloxacin in humans

BACKGROUND

Renal cell carcinoma (RCC) is the most common form of kidney cancer. Surgery is a standard procedure to resect the tumor during total (TN) or partial (nephron-sparing) nephrectomy (PN). Ciprofloxacin is most often administered at the usual intravenous dose of 100-400 mg/12 h. The application of such low doses of ciprofloxacin as 200 mg/24 h carries the risk of achieving subtherapeutic concentrations even in patients with limited renal function. The aim of the study was a comparison of concentrations and pharmacokinetics for ciprofloxacin at steady-state in patients after total and partial nephrectomy and evaluation of the effectiveness of the iv dose 200 mg/24 h against the theoretical value of MIC, 0.5 μg/ml.

METHODS

The research was carried out on two groups of patients after nephrectomy: total (group 1, n = 21; mean [SD], age, 62.9 [14.4] years; weight, 76.0 [14.6] kg; creatinine clearance, CL(CR), 90.7 [22.2] ml/min) and partial (group 2, n = 15; 61.7 [9.3] years; 87.8 [16.4] kg; CL(CR), 107.8 [36.4] ml/min). The patients were treated with ciprofloxacin in the dose of 200 mg/24 h (iv). Plasma concentrations of ciprofloxacin at steady state were measured with validated HPLC method with UV detection.

RESULTS

The mean values of plasma concentrations of ciprofloxacin at steady state in group 1 and 2 were: C(ss)(max), 2.012 and 1.345; C(ss)(min), 0.437 and 0.244 μg/ml, respectively. The main pharmacokinetic parameters for ciprofloxacin in group 1 and 2 were as follows: AUC((0-last)), 30.9 [17.9] and 19.5 [8.7] μg h/ml; AUMC((0-last)), 177.91 [11.1] and 91.9 [66.5] μg h(2)/ml; t(1/2β), 13.9 [7.7] and 9.8 [3.3] h; MRT, 16.5 [12.1] and 9.77 [5.4] h; V(d), 115.0 [67.2] and 142.2 [78.7] l; CL, 6.2 [3.3] and 10.8 [5.7] l/h, respectively. With the assumed MIC = 0.5 μg/ml, the values of C(ss)(max)/MIC < 10 and AUC/MIC < 125 were obtained in all the patients.

CONCLUSION

In our patients we observed significant differences in some pharmacokinetic parameters of ciprofloxacin after two types of nephrectomy.

Pharmacokinetics and pharmacodynamics of ciprofloxacin in critically ill patients after the first intravenous administration of 400 mg

PURPOSE

To investigate the pharmacokinetics and pharmacodynamics of ciprofloxacin in critically ill patients after the first intravenous administration of 400 mg.

MATERIAL/METHODS

Plasma concentrations were measured in 20 critically ill patients (mean [SD]; age, 55.5 [16.5] years; weight, 80.3 [16.9] kg; and creatinine clearance, 110.0 [71.5] mL/min). Four blood samples were drawn at the following time points 0, 0.5, 6 , 8 hours after infusion. Ciprofloxacin concentrations were determined by high-performance liquid chromatography.

RESULTS

In the cases where ciprofloxacin was applied in targeted antibiotic therapy the minimum inhibitory concentrations (MIC) were ≤0.5 mg/l. The maximum and minimum plasma concentrations of ciprofloxacin were 1.74 (0.58-7.90) and 0.45 (0.16-2.96) mg/l, respectively. The main pharmacokinetic parameters for ciprofloxacin in the analyzed patients were as follows: k(el), 0.21 h-1; t(1/2kel), 3.37 h; AUC(0-inf), 10.10 mg×h/l; AUMC(0-last), 15.36 mg×h(2)/l; MRT, 1.71 h; V(d), 214.8 l; Cl, 39.70 l/h. Considering the maximum value of MIC (0.5 mg/l) only 30% and 25% of analyzed patients had desired values of the PK/PD indexes AUIC>125 and C(max) /MIC>10, respectively.

CONCLUSIONS

The target plasma concentrations after the first dose of ciprofloxacin were reached only in a few critically ill patients. Considerable inter-subject variability for PK/PD parameters in ICU patients requires systematic monitoring.

Identification, pharmacologic considerations, and management of prostatitis

BACKGROUND

Prostatitis is a collection of signs and symptoms that occur as a result of inflammation or swelling of the prostate gland. There are many different causes for prostatitis, including infection; occasionally no clear etiology for the inflammation is found. Effective treatment often depends on identification of the cause, but a microbiologic organism is not always detectable, especially in cases of chronic prostatitis.

OBJECTIVE

The aim of this article was to review identification and treatment options for prostatitis, including pharmacologic and nonpharmacologic interventions.

METHODS

Relevant information was identified through a search of MEDLINE (1966-June 2010), International Pharmaceutical Abstracts (1970-June 2010), and EMBASE (1947-June 2010). Randomized, controlled trials that examined prostate cancer, benign prostatic hypertrophy, or procedures related to the prostate (ie, biopsies) were excluded.

RESULTS

A working classification system for prostatitis was developed in 1999, but there are few randomized controlled trials that distinguish between the various treatment options. Bacterial prostatitis can be acute or chronic but always requires some degree of antimicrobial therapy. Pharmacologic features of fluoroquinolones make them the preferred agents for most patients. These antibiotics can become trapped in a chronically inflamed prostate due to pH differences between prostatic tissue and serum. Many fluoroquinolones have penetration ratios (prostate level:serum level) of up to 4:1. A study in European men (N = 117) who received levofloxacin 500 mg/d with a diagnosis of chronic bacterial prostatitis demonstrated clinical success rates of 92% (95% CI 84.8%-96.5%), 77.4% (95% CI, 68.2-84.9%), 66.0% (95% CI, 56.2%-75.0%), and 61.9% (95% CI, 51.9%-71.2%) at 5-12 days, 1 month, 3 months, and 6 months after treatment. Additionally, there have been numerous randomized, placebo-controlled trials in patients with chronic prostatitis that have studied α-blockers, steroid inhibitors, anti-inflammatory agents, and bioflavonoids. Treatment responses to α-blockers appear to be greater with longer durations of therapy in α-blocker-naïve patients (National Institutes of Health-Chronic Prostatitis Symptom Index [NIH-CPSI] score reduction of at least 3.6 points after 6 weeks of tamsulosin therapy [P = 0.04] and up to 14.3 and 9.9 point NIH-CPSI score reductions with 14 weeks of terazosin and 24 weeks of alfuzosin therapy, respectively [P = 0.01 for both]). Combination therapy with an α-blocker, an anti-inflammatory, and a muscle relaxant does not appear to offer significant advantages over monotherapy (12.7 vs 12.4 point reduction in NIH-CPSI scores) and a stepwise approach to therapy involving antibiotics followed by bioflavonoids and then α-blockers appears to effectively reduce symptoms for up to 1 year in patients with chronic prostatitis (mean NIH-CPSI point reduction of 9.5 points compared with baseline, P < 0.0001). Patients who have had multiple unsuccessful treatment regimens may benefit from direct stimulation of the pelvic muscles through electromagnetic or electroacupuncture therapy.

CONCLUSIONS

Prostatitis can resemble various other medical conditions but proper classification and an understanding of the pharmacologic features and expectations of the medications used to treat it can help identify effective treatment strategies. Fluoroquinolones are the preferred agents for treating bacterial causes of prostatitis and have demonstrated efficacy in some cases of chronic prostatitis when an organism has not been identified. However, the use of agents with anti-inflammatory or antiadrenergic properties may be necessary in combination with or after trying antimicrobial agents.

Clinical use of gatifloxacin ophthalmic solution for treatment of bacterial conjunctivitis

Bacterial conjunctivitis is a common infectious disease of the eye, characterized by conjunctival hyperemia, eyelid edema, and purulent discharge. Although the prevalence and incidence are not well reported, bacterial conjunctivitis represents one of the most frequent causes of patient visits to both primary care physicians and ophthalmologists. Most cases of nongonococcal and nonchlamydial bacterial conjunctivitis are self-limiting and may resolve without intervention. There is a place for treatment, however, which allows for a shorter time to clinical and microbiological resolution which may decrease the mild morbidity, decrease health care costs of visits and potential complications, return patients back to school or the work force, and limit the potential spread of this communicable infection. Gatifloxacin ophthalmic solution is a broad spectrum 8-methoxyfluroroquinolone bactericidal antibiotic, with good activity against Staphylococcus aureus, Streptococcus species, and Gram-negative pathogens. It also has a relatively good resistance profile, making it a more than adequate choice in the treatment of bacterial conjunctivitis when therapy is warranted.

Safety considerations of fluoroquinolones in the elderly: an update

The fluoroquinolones ciprofloxacin, levofloxacin, moxifloxacin and gemifloxacin are widely used for the treatment of various types of bacterial infections. Overall, these antibacterial agents can be considered safe and well tolerated drugs. Comparative studies have evaluated the use of quinolones in elderly and younger populations. Although age per se does not seem to decrease their tolerability, specific adverse effects of the quinolones must be considered when they are chosen for antibacterial treatment. Renal function declines consistently with age and doses of renally excreted quinolones (e.g. ofloxacin, levofloxacin, gatifloxacin) need to be adjusted if a clinically relevant reduction of creatinine clearance is identified. Reactions of the gastrointestinal tract, such as nausea, dyspepsia, vomiting or diarrhoea, are among the most often registered adverse drug reactions during therapy with fluoroquinolones. Treatment with a quinolone causes diarrhoea less frequently than treatment with other classes of antimicrobials. Conflicting data have been published with respect to the incidence of Clostridium difficile-associated diarrhoea in quinolone-treated patients. Hypersensitivity reactions, often manifested on the skin, occur less commonly during therapy with quinolones than, for example, during therapy with beta-lactam antibacterials. Adverse reactions of the CNS are of particular concern in the elderly population. Given the CNS excitatory effects of quinolones, elderly patients should be monitored carefully for such symptoms. It is likely that many signs of possible adverse reactions, such as confusion, weakness, loss of appetite, tremor or depression, are often mistakenly attributed to old age and remain unreported. Quinolones should be used with caution in patients with known or suspected CNS disorders that predispose to seizures (e.g. severe cerebral arteriosclerosis or epilepsy). Quinolones can cause QT interval prolongation. They should be avoided in patients with known prolongation of the QT interval, patients with uncorrected hypokalaemia or hypomagnesaemia and patients receiving class IA (e.g. quinidine, procainamide) or class III (e.g. amiodarone, sotalol) antiarrhythmic agents. Tendinitis and tendon ruptures are recognized as quinolone-induced adverse effects that can occur during treatment or as late as several months after treatment. Chronic renal diseases, concomitant use of corticosteroids and age >60 years are known risk factors for quinolone-induced tendopathies. Overall, the specific adverse-effect profile of quinolones must be considered when they are chosen for treatment of bacterial infections. Because of physiological changes in renal function and when certain co-morbidities are present, some special considerations are necessary when elderly patients are treated with these drugs.

Review of third-and fourth-generation fluoroquinolones in ophthalmology: in-vitro and in-vivo efficacy

INTRODUCTION

Beginning with second-generation ciprofloxacin 0.3% and ofloxacin 0.3%, fluoroquinolones have been widely used in the treatment and prophylaxis of ocular infections. However, their in-vitro potencies have been decreasing steadily since their introduction. Third-generation levofloxacin 0.5% produces higher ocular tissue penetration, thereby reducing the risk of selecting for decreased fluoroquinolone potency. Fourth-generation gatifloxacin 0.3% and moxifloxacin 0.5% have structural modifications that both reduce risk of resistance and improve potency against Gram-positive bacteria. A new third-generation formulation, levofloxacin 1.5%, was recently introduced, demonstrating increased ocular penetration compared with gatifloxacin 0.3% but clinical equivalence to its second-generation parent, ofloxacin 0.3%, in two randomized trials.

METHODS

We investigated the therapeutic potential of levofloxacin 1.5% and compared it to that of existing fourth-generation fluoroquinolones. A MEDLINE search was conducted using the following search terms: moxifloxacin or gatifloxacin; levofloxacin; minimum inhibitory concentration or prevention or prophylaxis; keratitis or endophthalmitis.

RESULTS

Nine eligible studies published between 2002 and 2008 were identified, eight of which are presented. The five in-vitro studies demonstrated that moxifloxacin and gatifloxacin are statistically more potent than levofloxacin against Gram-positive organisms and similar in potency in most cases of Gram-negative bacteria. In-vivo animal models testing moxifloxacin or gatifloxacin against levofloxacin 0.5% (no clinical trials testing the efficacy of levofloxacin 1.5% have yet been published) demonstrated that fourth-generation agents were superior to third-generation levofloxacin 0.5% for prophylaxis of Gram-positive bacteria-induced infections and were equal to, or better than, levofloxacin 0.5% for the treatment of Gram-negative infections.

CONCLUSION

Fourth-generation agents have increased potency against Gram-positive bacteria compared with levofloxacin, while maintaining similar potency against Gram-negative bacteria. Although levofloxacin 1.5% has demonstrated superior ocular penetration relative to gatifloxacin, the limited available data do not suggest this translates into superior clinical activity compared with moxifloxacin, which has significantly greater ocular penetration and better Gram-positive potency than gatifloxacin.

Antimicrobial safety: focus on fluoroquinolones

BACKGROUND/PURPOSE

Infrequent toxicities associated with certain drugs and drug classes have recently gained much attention from different health-care perspectives. To protect the patient, continued surveillance of safety and tolerability data is essential. Data from preclinical testing, phase 1-3 trials, and postmarketing surveillance may be used to objectively assess the risks associated with a specific drug or family of compounds. This review summarizes safety and tolerability data for the quinolones.

MAIN FINDINGS

The most common adverse events associated with the quinolone class involve the gastrointestinal tract (nausea and diarrhea) and central nervous system (CNS) (headache and dizziness). These adverse events are usually mild and do not require discontinuation of therapy. Uncommon and potentially serious quinolone-related adverse events involve the cardiovascular system (rate-corrected electrocardiographic QT interval prolongation), musculoskeletal system (tendinitis and tendon rupture), endocrine system (glucose homeostasis dysregulation), renal system (crystalluria, interstitial nephritis, and acute renal failure), and the CNS (seizures). Severe idiosyncratic adverse events are specific to individual agents that may share some structural congruity, such as the 1-(2,4)-difluorophenyl group shared by trovafloxacin (associated with hepatitis), temafloxacin (associated with hemolytic-uremic syndrome), and tosufloxacin (associated with eosinophilic pneumonitis). Overall, discontinuation rates from clinical trials were <4% for the currently marketed quinolones. Quinolones with higher discontinuation rates, such as trovafloxacin (7.0%) and grepafloxacin (6.4%), are no longer available for general use.

CONCLUSIONS

The currently marketed quinolones are well tolerated, with safety profiles similar to those of other antimicrobial classes. Although adverse effects are unusual, some, including tendinitis and CNS-related effects, are more common with quinolones than with other antimicrobial classes. Rare adverse effects attributed to some members of the quinolone family (e.g., Torsades de Pointes, hepatotoxicity, and dysglycemias) are more likely to occur in select "susceptible" populations. These adverse events can often be circumvented by avoiding exposure to the specific quinolone. In some cases, the therapeutic value offered by a quinolone may outweigh its potential risks.

The changing face of malignant (necrotising) external otitis: clinical, radiological, and anatomic correlations

Malignant (necrotising) external otitis is an invasive infection of the external auditory canal. Although elderly patients with diabetes remain the population most commonly affected, immunosuppressed individuals (eg, from HIV infection, chemotherapy, etc) are also susceptible to malignant external otitis. Pseudomonas aeruginosa is isolated from the aural drainage in more than 90% of cases. The pathophysiology is incompletely understood although aural water exposure (eg, irrigation for cerumen impaction) has been reported as a potential iatrogenic factor. The typical patient presents with exquisitely painful otorrhoea. If untreated, cranial neuropathies (most commonly of the facial nerve) can develop due to subtemporal extension of the infection. The diagnosis of malignant external otitis is based on a combination of clinical findings, an increased erythrocyte sedimentation rate, and radiographic evidence of soft tissue with or without bone erosion in the external canal and infratemporal fossa. Treatment consists of prolonged administration (6-8 weeks) of an antipseudomonal agent (typically an orally administered quinolone). With the introduction and widespread use of both oral and topical quinolones, there are reports of less severe presentation of malignant external otitis and even the emergence of ciprofloxacin resistance. Reservation of systemic quinolones for the treatment of invasive ear infections is recommended.

Fluoroquinolones in the elderly: safety considerations

Fluoroquinolones such as ciprofloxacin, levofloxacin, moxifloxacin and gatifloxacin are widely used for the treatment of bacterial infections. Fluoroquinolone-induced adverse effects have not been reported to occur with increased frequency in the elderly, but large trials comparing the tolerability in aged and young individuals are not available. Renal function declines consistently with age and recommendations for dosage changes of renally eliminated fluoroquinolones (ofloxacin, levofloxacin, gatifloxacin) are related to changes in kidney function rather than to age per se. However, during routine clinical work, creatinine clearance data are usually not available; thus it seems more practical to recommend dosage adjustment for elderly individuals in whom low creatinine clearance values can be expected. Reactions of the gastrointestinal tract are the most often observed adverse effects during therapy with fluoroquinolones; however, compared with many other antibacterials, fluoroquinolones are less frequently associated with diarrhoea. Similarly, hypersensitivity reactions, as observed during therapy with penicillins and other beta-lactam agents, occur more rarely during fluoroquinolone therapy. Adverse reactions of the CNS are of particular concern for the elderly population. Elderly patients with impairments of the CNS (e.g. epilepsy, pronounced arteriosclerosis) should be treated with fluoroquinolones only under close supervision. Probably, many signs of possible adverse reactions such as confusion, weakness, loss of appetite, tremor or depression are often mistakenly attributed to old age and remain unreported. Fluoroquinolones can cause QT interval prolongation. Therefore, they should be avoided in patients with known prolongation of the QT interval, patients with uncorrected hypokalaemia or hypomagnesaemia and patients receiving class IA (e.g. quinidine, procainamide) or class III (e.g. amiodarone, sotalol) antiarrhythmic agents. Chondrotoxicity of fluoroquinolones, as observed in immature animals, has led to restricted use in paediatric patients, but there is no indication that similar effects could occur in joint cartilage of adults. Tendinitis and tendon ruptures have occurred in rare cases as late as several months after treatment with some fluoroquinolones. Chronic renal diseases, concomitant use of corticosteroids and age over 60 years have been recognised as risk factors for fluoroquinolone-induced tendon disorders. Overall, the widely used fluoroquinolones discussed in this review are generally well tolerated. Nevertheless, as with all drugs, their specific adverse effect profiles must be considered when they are chosen for treatment of bacterial infections. Because of physiological changes in renal function and in case of certain comorbidities, some special considerations are necessary when fluoroquinolones are used to treat elderly patients.

Retrospective analysis of the safety profile of oral and intravenous ciprofloxacin in a geriatric population

BACKGROUND

Ciprofloxacin is a broad-spectrum fluoroquinolone antibiotic used in the treatment of a wide range of mild to moderate gram-positive and gram-negative infections. Although extensive information is available on the safety profile of ciprofloxacin in adults, few published data exist regarding the tolerability and toxicity of this drug in patients aged > or = 65 years.

OBJECTIVES

The objectives of this retrospective analysis were to compare the safety profile of ciprofloxacin in patients aged > or = 65 years versus patients aged <65 years and to compare the adverse-event profile of ciprofloxacin with that of other comparator antimicrobial agents used in clinical trials.

METHODS

We retrospectively reviewed 23 prospective, controlled anti-infective clinical trials in the US Bayer ciprofloxacin database that included patients aged > or = 65 years. These trials comprised the submission file of the original and supplemental New Drug Application for ciprofloxacin. The incidence of treatment-emergent and drug-related adverse events was assessed.

RESULTS

Of the 6863 patients in these 23 clinical trials, 3579 received ciprofloxacin therapy and 3284 received comparator antimicrobial agents. Of the ciprofloxacin-treated patients, 898 (25.1%) were aged > or = 65 years; 887 (27.0%) of the patients who received comparator antimicrobial agents were aged > or = 65 years. Among ciprofloxacin-treated patients, drug-related adverse events were reported more often in those aged <65 years (24.0%) compared with those aged > or = 65 years (17.9%). The incidence of drug-related adverse events in the comparator group was also higher in those aged <65 years (25.1%) than in those aged > or = 65 years (16.8%). Premature discontinuation due to any adverse event was reported in 3.9% (105 of 2681) and 3.7% (33 of 898) of ciprofloxacin-treated patients aged <65 years and > or = 65 years, respectively. Corresponding rates for the comparator antimicrobial group were 3.9% (93 of 2397) and 3.8% (34 of 887), respectively, for patients aged <65 years and > or = 65 years. The most common drug-related adverse events reported for ciprofloxacin-treated patients aged <65 years and > or = 65 years were digestive system-related (18.1% and 11.4%, respectively) and central nervous system-related events (6.6% and 4.9%, respectively).

CONCLUSIONS

This retrospective analysis suggests that there is no clinically important difference in the safety profile of ciprofloxacin in patients aged > or = 65 years versus patients aged <65 years.

Ciprofloxacin disposition in elderly patients with LRTI being treated with sequential therapy (200 mg intravenously twice daily followed by 500 mg per os twice daily): comparative pharmacokinetics and the role of therapeutic drug monitoring

Ciprofloxacin is a fluoroquinolone antibiotic effective in the treatment of lower respiratory tract infections (LRTI). The aim of this study was to assess the pharmacokinetic appropriateness of a standard switch i.v./os regimen of ciprofloxacin (200 mg i.v. bid for 3 to 5 days followed by 500 mg os bid for 7 to 10 days) frequently used in routine clinical practice in the treatment of elderly patients with mild to moderate LRTI. The pharmacokinetic study was performed on a cohort of 17 elderly inpatients. Blood samples were collected in steady state conditions at appropriate intervals. Ciprofloxacin serum concentrations were analyzed using an HPLC method and pharmacokinetic parameters were estimated using the WinNonlin software package. The pharmacokinetic data were at least partially different from those obtained by other authors in elderly patients (lower Cmax after i.v. administration and higher CL both after i.v. and oral administration). Cmax after a 1-hour 200-mg infusion were similar to those observed during the 500 mg bid peroral regimen (2.1 +/- 0.9 mg/L vs 2.6 +/- 1.0 mg/L; p = 0.054). The absolute oral bioavailability (84.1%) allowed a total body exposure 2.1-fold greater after 500 mg bid oral administration than after 200 mg bid i.v. administration (AUC(0-tau) 11.4 +/- 4.3 mg/L x h vs 5.5 +/- 1.8 mg/L x h). The results show that in malabsorption-free elderly patients a regimen of 500 mg os bid may be considered a valid therapeutic approach from the beginning of therapy for mild to moderate LRTI caused by sensitive microorganisms (MIC < 0.1 mg/L). In fact, because the peak serum level to MIC ratio (Cmax/MIC) and the area under the inhibitory serum concentration-time curve (AUIC24 = AUC24h/MIC) are actually considered major pharmacodynamic determinants for the outcome of treatment with fluoroquinolones, this regimen could guarantee both a better pharmacokinetic exposure than the 200 mg i.v. bid regimen and a cost-effective treatment of LRTI. However, because of the great pharmacokinetic interindividual variability observed a normalized dosage per kg (3 mg/kg/12h i.v. and 8 mg/kg/12h os) should be considered, especially for body weight >90 kg and, whenever possible, TDM of AUC(0-tau) or at least of Cmax should be performed to individualize therapy in this subpopulation.

Ciprofloxacin. An updated review of its pharmacology, therapeutic efficacy and tolerability

Ciprofloxacin is a broad spectrum fluoroquinolone antibacterial agent. Since its introduction in the 1980s, most Gram-negative bacteria have remained highly susceptible to this agent in vitro; Gram-positive bacteria are generally susceptible or moderately susceptible. Ciprofloxacin attains therapeutic concentrations in most tissues and body fluids. The results of clinical trials with ciprofloxacin have confirmed its clinical efficacy and low potential for adverse effects. Ciprofloxacin is effective in the treatment of a wide variety of infections, particularly those caused by Gram-negative pathogens. These include complicated urinary tract infections, sexually transmitted diseases (gonorrhoea and chancroid), skin and bone infections, gastrointestinal infections caused by multiresistant organisms, lower respiratory tract infections (including those in patients with cystic fibrosis), febrile neutropenia (combined with an agent which possesses good activity against Gram-positive bacteria), intra-abdominal infections (combined with an antianaerobic agent) and malignant external otitis. Ciprofloxacin should not be considered a first-line empirical therapy for respiratory tract infections if penicillin-susceptible Streptococcus pneumoniae is the primary pathogen; however, it is an appropriate treatment option in patients with mixed infections (where S. pneumoniae may or may not be present) or in patients with predisposing factors for Gram-negative infections. Clinically important drug interactions involving ciprofloxacin are well documented and avoidable with conscientious prescribing. Recommended dosage adjustments in patients with impaired renal function vary between countries; major adjustments are not required until the estimated creatinine clearance is < 30 ml/min/1.73m2 (or when the serum creatinine level is > or = 2 mg/dl). Ciprofloxacin is one of the few broad spectrum antibacterials available in both intravenous and oral formulations. In this respect, it offers the potential for cost savings with sequential intravenous and oral therapy in appropriately selected patients and may allow early discharge from hospital in some instances. In conclusion, ciprofloxacin has retained its excellent activity against most Gram-negative bacteria, and fulfilled its potential as an important antibacterial drug in the treatment of a wide range of infections. Rational prescribing will help to ensure the continued clinical usefulness of this valuable antimicrobial drug.

Multicenter, phase IV evaluation of intravenous ciprofloxacin as initial therapy in patients with lower respiratory tract, urinary tract, and skin/skin structure infections

A prospective, open-label, multicenter, Phase IV study of the efficacy and safety of intravenous (IV) ciprofloxacin (400 mg by 60-minute infusion every 12 hours) in the treatment of lower respiratory tract infections (LRTIs), urinary tract infections (UTIs), and skin/skin structure infections (SSSIs) in hospitalized patients was conducted in 1991. After a minimum of 3 days of IV therapy, patients could be switched to oral therapy with any antimicrobial. Of 360 patients who were valid for investigator assessment of clinical outcome at the end of IV therapy, a favorable outcome (cure and improvement in infection) was reported in 337 (94%) patients and failure was reported in 23 (6%) patients. Of 330 patients valid for investigation assessment of clinical outcome at the end of all therapy (IV treatment alone or IV treatment followed by an oral antimicrobial), a favorable outcome was noted in 311 (94%) patients, and failure occurred in 19 (6%) patients. Adverse events were noted in 72 (9%) of 782 patients and led to premature discontinuation of IV therapy in 23 (3%) patients. IV ciprofloxacin appears to be effective and safe in the management of mild-to-moderate LRTI and SSSI and mild, moderate, or severe UTI in hospitalized patients.