Safety of intravenous ciprofloxacin. A review

A VigiBase Descriptive Study of Fluoroquinolone-Associated Peripheral Nervous System Disorders

Background: Recent drug safety concerns described fluoroquinolone (FQ)-induced peripheral nervous system reactions. The objective of this study was to characterize such reports from VigiBase. Methods: The analysis included FQ-induced peripheral nervous system disorder adverse drug reaction (ADR) reports (up to July 2019). We looked into the disproportionality data in terms of proportional reporting ratio (PRR) and information component (IC) values, and descriptive analysis was performed for FQ-ADRs positive associations (ADRs, suspected FQs, potential risk factors, such as associated therapy and underlying disease). Results: Disproportionality analysis revealed 4374 reports (3531 serious) with peripheral nervous system ADRs associated with at least three FQs (neuropathy peripheral, 5492; neuralgia, 481; polyneuropathy, 220; sensory loss, 99; peripheral sensorimotor neuropathy, 39). Among these, both time-to-onset and duration of reaction were mostly between 1–7 days and ≥30 days. Most of the ADRs were not recovered/resolved at the time of reporting. Conclusion: The results augment the existing data on FQ safety concerns, specifically their potential effect on the nervous system.

Can antibiotic preference affect bleeding in percutaneous nephrolithotomy? Retrospective comparative study of two commonly used antibiotics

Objective

Bleeding is one of the most common and alarming complication of percutaneous nephrolithotomy (PCNL). In this study, we aimed to compare the effects of ciprofloxacin and cefuroxime on the bleeding in PCNL procedures.

Methods

The study was a retrospective analysis of 97 patients who underwent PCNL between February 2011 and June 2017. We just included the patients who had single tract lower pole PCNL for more objective evaluation of bleeding in the study. The patients were divided into two groups as ciprofloxacin group (Group-I, n:40) and cefuroxime group (Group-II, n:56) according to the type of antibiotic used in the operation. Patient age, gender, body mass index, stone size, preoperative INR, preoperative and postoperative platelet counts and difference, operative time, need for blood transfusion, postoperative fever, hospital stay, postoperative hemoglobin and hematocrit drop were analyzed.

Results

There was no statistically significant difference in patients' gender distribution, body mass index, preoperative INR, preoperative and postoperative platelet counts, preoperative and postoperative platelet difference, duration of operation, hospital stay, postoperative fever and need for postoperative blood transfusion between two antibiotic groups (p > 0.05). Mean patient age was 42,75±16,97 in Group-I and 35,54±14,71 in Group-II (p < 0.05). The mean stone size of Group-I and Group-II were 27,23±7,05 mm and 30,59±8,20, respectively (p < 0.05). The mean postoperative hemoglobin and hematocrit drop were significantly higher in Group-I than in Group-II. The mean hemoglobin drop was 1,73±0,95 for Group-I and 1,28±0,67 for Group-II (p < 0.05). The mean hematocrit drop was 5,17±2,76 for Group-I and 3,80±1,99 for Group-II (p < 0.05).

Conclusion

On the basis of the results of the initial study, the antibiotic preference in patients undergoing surgery may be one of the bleeding factors during and after PCNL.

Hematologic Adverse Effects of Prolonged Piperacillin-Tazobactam Use in Adults

Objective:

We aimed to find the incidence and risk factors of hematologic adverse effects of piperacillin-tazobactam (TZP).

Materials and Methods:

Adult patients who used TZP for more than 10 days were included in the study.

Results:

The incidence of leukopenia, neutropenia, and eosinophilia in 110 TZP therapy episodes was found to be 16.3%, 10%, and 10%, respectively. Lower Charlson Comorbidity Index score, lower initial leukocyte count, combination of TZP with another antibiotic, and total duration of TZP therapy were found to be independent risk factors for leukopenia, while initial higher eosinophil count (IHEC) and usage of TZP for >20 days were independent risk factors for neutropenia and IHEC and total duration of TZP therapy were independent risk factors for eosinophilia.

Conclusion:

Longer duration of therapy, combination with other antibiotics, younger age with fewer comorbidities, and IHEC could result in hematologic adverse effects in patients treated with TZP. Patients with IHEC may be more prone to allergic reactions, so immunological mechanisms may facilitate the development of hematological adverse effects of TZP.

Antibiotic-induced neurotoxicity

Antibiotic neurotoxicity is rare but can cause significant morbidity when it occurs. The risk of antibiotic neurotoxicity appears to be highest in patients who are older, have impaired renal function, or have preexisting neurologic conditions. This review describes the clinical features of the most common antibiotic toxicities affecting the nervous system: seizures, encephalopathy, optic neuropathy, peripheral neuropathy, and exacerbation of myasthenia gravis.

Comparison of adverse events between oral and intravenous formulations of antimicrobial agents: a systematic review of the evidence from randomized trials

BACKGROUND

Some clinicians may favor a strategy of early switch to oral antimicrobial therapy for patients responding to initial intravenous therapy. An important relevant consideration refers to the comparative safety and tolerability between oral and intravenous antimicrobial therapy. LITERATURE SEARCH/STUDY SELECTION: We sought to evaluate the above-mentioned issue by performing a systematic review of randomized studies comparing the occurrence of adverse events between oral and intravenous antimicrobial therapy with the same agents.

FINDINGS

Ten relevant studies (five randomized controlled trials, three randomized cross-over studies, and two randomized, placebo-controlled, parallel-design studies) were included. Seven of the studies evaluated antibacterials (fluoroquinolones in four, and telithromycin, amoxicillin-clavulanic acid, and linezolid in one study each, respectively), whereas two studies evaluated ganciclovir, and one evaluated isavuconazole. No difference was observed in the rate of total adverse events between oral and intravenous administration of the same antimicrobial agents in any of the included studies that reported specific relevant data. Injection site reactions were noted more frequently with intravenous treatment in one study. No serious drug-related adverse events were reported, while study withdrawals due to adverse events did not considerably differ between the compared groups in any of the included studies.

CONCLUSION

There are only limited comparative data regarding the adverse events associated with the administration of the same antimicrobial agents by the oral and intravenous route. Our review indicates that the adverse event profile of oral and intravenous antimicrobial therapy does not differ considerably; however, this issue requires validation by further studies.

Decision-Making Analysis for Selection of Antibiotic Treatment in Intra-Abdominal Infection Using Preference Measurements

BACKGROUND

Antimicrobial therapy of abdominal infections is important to the prognosis of affected patients. The choice of antimicrobial therapy must consider effectiveness, safety, cost, and antibiotic resistance, among numerous factors. However, in reality, decisions are made assuming bioequivalence between regimens, without considering the specific attributes of any particular regimen. The objective was to determine the best antibiotic regimen for patients with community-acquired abdominal infection on the basis of a decision analysis that included effectiveness as well as safety, measured as adverse effects.

METHODS

A decision tree was built using information from a systematic review of the literature on the effectiveness of antimicrobial regimens tested in randomized clinical trials (RCTs) and the frequency and severity of adverse effects. The quality of the articles was assessed with the Oxford criteria for RCTs. The main outcome was preferences reported by surgeons, measured on a numeric scale. Preferences were obtained using a standard survey that reported each adverse effect with its respective intensity, reversibility, sequelae, duration of symptoms, and necessity for change of antibiotic. Each of the surgeons had to assign a value blindly from 0 to 10, where 10 was the most severe. A sensitivity analysis was conducted varying the frequency of adverse effects.

RESULTS

The regimens analyzed were amikacin-metronidazole, amikacin-clindamycin, ciprofloxacin-metronidazole, ampicillin-sulbactam, ceftriaxone-metronidazole, piperacillin-tazobactam, and ertapenem. The perceived severity of adverse effects reported were: Acute neuromuscular blockade (8.0), severe allergic reaction (7.5), ototoxicity (7.4), nephrotoxicity (7.1), antibiotic-associated colitis (7.0), peripheral neuropathy (5.3), general neurological symptoms (4.9), gastrointestinal symptoms (3.1), and other general symptoms (2.6). Favored regimens were ceftriaxone-metronidazole (1.15), ampicillin-sulbactam (1.24), piperacillin-tazobactam (1.27) and ertapenem (1.28). These strategies dominated the other therapeutic schemes. Sensitivity analysis showed no changes in the dominance reported when the frequency of adverse effects was maintained in the known clinical range.

CONCLUSIONS

Antibiotic regimens that contain aminoglycosides are not bioequivalent to those without aminoglycosides when effectiveness and adverse effects are considered simultaneously. Antibiotic regimens that do not use aminoglycosides must be the first line of treatment for abdominal sepsis acquired in the community.

[Pharmacological properties and expected clinical role of an injectable new quinolone antibiotic, pazufloxacin mesilate]

Pazufloxacin mesilate (PZFX: Pasil INJECTION, Pazucross INJECTION) is a novel injectable quinolone antibiotic that was discovered by Toyama Chemical Co., Ltd. and codeveloped by Toyama Chemical Co. Ltd. and Mitsubishi Pharma Corporation. Laboratory studies indicated that PZFX reached high plasma levels quickly after intravenous administration, and it exhibited weak convulsion inducing activity, low local irritant effect, and less hypotensive activity, all of which are generally recognized as side effects associated with other injectable quinolones. PZFX has potent antibacterial and bactericidal activities against cephalosporin-, carbapenem-, and aminoglycoside-resistant strains. These favorable antibacterial and bactericidal activities gave PZFX superior therapeutic effects, compared to injectable cephalosporin antibiotics, on experimental animal infection models caused by those resistant strains. Clinical studies also revealed PZFX was as safe and effective as the injectable cephalosporin, ceftazidime, against various moderate to severe infections. Furthermore, PZFX showed good clinical effects on the infections resistant to chemotherapy by the other antimicrobial agents. These results indicate that PZFX is a viable choice for various bacterial infections. In this review, results of laboratory and clinical studies are summarized and the clinical role of PZFX among the injectable antimicrobials is discussed.

Fluoroquinolone adverse effects and drug interactions

Extensive pharmacologic and clinical development of quinolone antimicrobial agents has resulted in improved antimicrobial activity, pharmacokinetic features, toxicity, and drug-drug interaction profiles. Nalidixic acid and other early quinolones had limited use due to poor pharmacokinetics, relatively narrow antimicrobial spectrum of activity, and frequent adverse effects. Beginning with the development of fluoroquinolones, such as norfloxacin and ciprofloxacin, in the 1980s, the agents assumed a greatly expanded clinical role because of their broad antimicrobial spectrum of action, improved pharmacokinetic properties, and more acceptable safety profile. Although the pharmacokinetics and efficacy of the drugs have improved significantly, a major area of continued emphasis is to further reduce the frequency and severity of adverse events and drug-drug interactions. Older agents such as ciprofloxacin and ofloxacin are still extensively prescribed, but the focus of this article is on the newer fluoroquinolones (levofloxacin and other drugs that have been approved or have been under investigation since approximately 1997).

Comparison of fluoroquinolone pharmacokinetic parameters after treatment with marbofloxacin, enrofloxacin, and difloxacin in dogs

Plasma, urine, and skin drug concentrations were determined for dogs (n=12) given five daily oral doses of marbofloxacin (MAR) (2.75 mg/kg), enrofloxacin (ENR) (5.0 mg/kg) or difloxacin (DIF) (5.0 mg/kg). Concentrations of the active metabolite of ENR, ciprofloxacin (CIP), were also determined. The three-period, three-treatment crossover experimental design included a 21-day washout period between treatments. Area under the plasma drug concentration vs. time curve (AUC0-last, microg/mLxh of MAR was greater than for ENR, CIP, ENR/CIP combined, and DIF. Maximum concentration (Cmax) of MAR was greater than ENR, CIP, and DIF. Time of maximum plasma concentration (Tmax) was similar for MAR and DIF; Tmax occurred earlier for ENR and later for CIP. Plasma half-life (t1/2) of MAR was longer than for ENR, CIP, and DIF. Urine concentrations of DIF were less than MAR or ENR/CIP combined, but urine concentrations of MAR and ENR/CIP combined did not differ. DIF skin concentrations were less than the concentrations of MAR or ENR/CIP combined 2 h after dosing, but skin concentrations of MAR and ENR/CIP combined did not differ.

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.

The safety profile of the fluoroquinolones

BACKGROUND

Premarketing trials showed the fluoroquinolone agents to have a favorable side-effect profile, with treatment-related adverse events comprising gastrointestinal, central nervous system, and dermatologic effects that were generally mild and reversible on cessation of treatment. However, postmarketing surveillance studies have identified severe adverse events, including severe anaphylaxis, QTc-interval prolongation, and potential cardiotoxicity, associated with 3 quinolone agents that either resulted in the removal of the agent from the market (temafloxacin and grepafloxacin) or significantly restricted its use due to substantial mortality and morbidity associated with liver toxicity (trovafloxacin). To date, there have been no such significant adverse events associated with the older fluoroquinolone agents, including ciprofloxacin, ofloxacin, norfloxacin, and levofloxacin. However, there are fewer data from postmarketing surveillance studies on the most recently approved agents, such as moxifloxacin and gatifloxacin, or agents awaiting approval, such as gemifloxacin.

OBJECTIVE

This paper examines safety data from the premarketing trials and postmarketing surveillance studies of fluoroquinolones available in the United States.

METHODS

A MEDLINE search was performed to identify all English-language studies published since 1980 concerning the safety profiles of the fluoroquinolones.

CONCLUSIONS

The fluoroquinolone antibacterial agents offer broad-spectrum therapy in patients with a variety of infections. Given similar spectra of activity, the choice between quinolones may be based on differences in efficacy and safety or tolerability profiles. Most drug reactions involving these agents are minor and reversible on discontinuing treatment, but adverse effects can be associated with significant mortality and morbidity, as was seen in the case of trovafloxacin and temafloxacin.

Characterization of histamine release induced by fluoroquinolone antibacterial agents in-vivo and in-vitro

Characterization of histamine release induced by fluoroquinolone antibacterial agents, levofloxacin and ciprofloxacin, was investigated in-vivo and in-vitro. Intravenous injection of levofloxacin and ciprofloxacin at 1-10 mg kg(-1) produced dose-related elevations in plasma histamine level in anaesthetized dogs. In contrast, levofloxacin was devoid of plasma histamine increment in anaesthetized rats at 100 mg kg(-1), whereas ciprofloxacin at the same dose caused endogenous histamine release. Levofloxacin and ciprofloxacin induced non-cytotoxic secretion of histamine from all mast cells tested in a concentration-dependent manner, whereas rat skin and peritoneal mast cells were thirty- to one-hundred-times less sensitive to the effect of fluoroquinolones as compared with the canine skin mast cells. These results suggest that the functional heterogeneity of mast cells from different species in histamine releasing activity of fluoroquinolones may exist, and that mast cells from the dog appear to be particularly sensitive to the effect of the fluoroquinolones.

Mechanism of histamine release induced by levofloxacin, a fluoroquinolone antibacterial agent

The present study was designed to clarify the mechanism of histamine release caused by levofloxacin, a fluoroquinolone antibacterial agent, using rat peritoneal mast cells. Levofloxacin induced a concentration-dependent histamine secretion from 300 microg/ml without lactate dehydrogenase leakage, and the release was rapidly completed within 30 s. This action was dependent on temperature, energy, pH and intracellular Ca(2+), similarly to the effect of compound 48/80, a basic compound. Unlike that with the calcium ionophore A23187, histamine secretion due to levofloxacin or compound 48/80 was prevented by pretreatment with either pertussis toxin or benzalkonium chloride, a selective inhibitor of G proteins of G(i) subtypes. Moreover, the histamine release elicited by levofloxacin or compound 48/80 was suppressed by hydrolysis of sialic acid residues on the cell surface brought about by neuraminidase. These results demonstrate that the mechanism by which levofloxacin exerts histamine release may be closely linked to activation of pertussis toxin-sensitive G proteins.

Antibiotic-induced convulsions

Convulsive episodes are associated with the use of a number of antimicrobial agents. Although seizures may be a feature of the disease being treated, antibiotics should be considered possible causes of seizures, particularly if suggested by temporal relationships between seizure activity and drug administration. The astute clinician should be aware of the clinical settings in which antibiotic-induced seizures occur, be familiar with likely agents and their mechanisms of toxicity, and be prepared to institute appropriate management directed at this adverse effect of antimicrobial therapy.

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.

Toxicity of quinolone antimicrobial agents

An approach to minimization of toxicity of a new compound is to elucidate the mechanisms of toxicity of analogous compounds and to clarify their structure-toxicity relationships. A problem with this approach, however, is that such elucidation remains difficult. For quinolones, some improvements in this mechanistic approach have been achieved in the central nervous system (CNS), particularly with regard to their interaction with non-steroidal anti-inflammatory drugs (NSAIDs), and in genotoxicity and phototoxicity studies, particularly in comparison with other toxicities, such as to the cardiovascular, gastrointestinal, bone, reproductive, and developmental systems. This review concentrates on a description of the known effects of quinolones on various organ systems in experimental animals and humans. Given the logarithmic increase in the synthesis of new quinolones, it is questionable whether these drugs share similar safety and efficacy. Nevertheless, this mechanistic approach to the investigation and minimization of toxicity has produced satisfactory results to date and deserves to be continued.

Treatment of severe pneumonia in hospitalized patients: results of a multicenter, randomized, double-blind trial comparing intravenous ciprofloxacin with imipenem-cilastatin. The Severe Pneumonia Study Group

Intravenously administered ciprofloxacin was compared with imipenem for the treatment of severe pneumonia. In this prospective, randomized, double-blind, multicenter trial, which included an intent-to-treat analysis, a total of 405 patients with severe pneumonia were enrolled. The mean APACHE II score was 17.6, 79% of the patients required mechanical ventilation, and 78% had nosocomial pneumonia. A subgroup of 205 patients (98 ciprofloxacin-treated patients and 107 imipenem-treated patients) were evaluable for the major efficacy endpoints. Patients were randomized to receive intravenous treatment with either ciprofloxacin (400 mg every 8 h) or imipenem (1,000 mg every 8 h), and doses were adjusted for renal function. The primary and secondary efficacy endpoints were bacteriological and clinical responses at 3 to 7 days after completion of therapy. Ciprofloxacin-treated patients had a higher bacteriological eradication rate than did imipenem-treated patients (69 versus 59%; 95% confidence interval of -0.6%, 26.2%; P = 0.069) and also a significantly higher clinical response rate (69 versus 56%; 95% confidence interval of 3.5%, 28.5%; P = 0.021). The greatest difference between ciprofloxacin and imipenem was in eradication of members of the family Enterobacteriaceae (93 versus 65%; P = 0.009). Stepwise logistic regression analysis demonstrated the following factors to be associated with bacteriological eradication: absence of Pseudomonas aeruginosa (P < 0.01), higher weight (P < 0.01), a low APACHE II score (P = 0.03), and treatment with ciprofloxacin (P = 0.04). When P. aeruginosa was recovered from initial respiratory tract cultures, failure to achieve bacteriological eradication and development of resistance during therapy were common in both treatment groups (67 and 33% for ciprofloxacin and 59 and 53% for imipenem, respectively). Seizures were observed more frequently with imipenem than with ciprofloxacin (6 versus 1%; P = 0.028). These results demonstrate that in patients with severe pneumonia, monotherapy with ciprofloxacin is at least equivalent to monotherapy with imipenem in terms of bacteriological eradication and clinical response. For both treatment groups, the presence of P. aeruginosa had a negative impact on treatment success. Seizures were more common with imipenem than with ciprofloxacin. Monotherapy for severe pneumonia is a safe and effective initial strategy but may need to be modified if P. aeruginosa is suspected or recovered from patients.

Use of the quinolones for the prophylaxis and therapy of infections in immunocompromised hosts

The prevention and treatment of infections are major issues of supportive care in patients with haematological malignancies. Because of their broad antimicrobial activity, the use of fluoroquinolones for prophylaxis in neutropenic patients has been extensively studied. In comparison with placebo, norfloxacin reduces the incidence of Gram-negative infections, whereas Gram-positive bacterial and fungal infections remain unaffected. Ofloxacin and enoxacin also bacterial and fungal infections remain unaffected. Ofloxacin and enoxacin also produce a reduction in fever and documented infections. In randomized studies comparing ciprofloxacin with cotrimoxazole (trimethoprim/sulfamethoxazole) plus colistin (each in combination with nonabsorbable antifungal agents), conflicting results were obtained. The incidence of documented Gram-negative bacterial infections was markedly reduced by ciprofloxacin prophylaxis; however, the number of Gram-positive infections may increase dramatically. Combining ciprofloxacin with a macrolide antibiotic in an attempt to prevent streptococcal infections can result in breakthrough bacteraemias due to resistant Gram-positive pathogens. Empirical antimicrobial therapy after quinolone prophylaxis should also be directed against microorganisms susceptible to quinolones, since sustained eradication by oral administration cannot be assumed with certainty. Clinical trials comparing intravenous quinolones in combination with aminoglycosides with widely used standard regimens for the treatment of infections in cancer patients indicate equivalent efficacy; however, in studies of ciprofloxacin alone, response rates were significantly lower compared with standard combinations. Therefore, quinolone monotherapy as empirical treatment in febrile neutropenic patients cannot be recommended.

Overview of fluoroquinolone safety

The safety of the fluoroquinolone antimicrobial agents is reviewed, discussing documented and potential clinical and laboratory adverse effects and drug-drug interactions. In prospective, randomized, double-blind clinical trials comparing fluoroquinolones to nonquinolone drugs or placebo, the fluoroquinolones were not significantly different (22 studies) or were superior (5 studies) to comparison agents but were only rarely more toxic (2 studies). Adverse effects included mild gastrointestinal toxicities and less common but more problematic central nervous system toxicities. Clinically important interactions occurred with coadministration of antacids and all fluoroquinolones and with theophylline and enoxacin and to a lesser extent ciprofloxacin and pefloxacin but not other fluoroquinolones. Potential adverse effects such as cartilage damage, DNA damage, teratogenicity, and crystalluria, while of concern, have not as yet been shown to be of clinical importance. Therapy of bacterial infections in children and adolescents is relatively contraindicated, but growing clinical experience with treatment of these patients has not so far revealed serious bone or cartilage toxicity. The fluoroquinolones thus far have exhibited a favorable safety profile, but our clinical experience is still limited, and monitoring for as yet unappreciated toxicities is warranted.

Safety of ciprofloxacin in children: worldwide clinical experience based on compassionate use. Emphasis on joint evaluation

Six hundred and thirty four adolescents and children aged three days to 17 years treated with ciprofloxacin on a compassionate basis were analysed for drug safety. 62% of the ciprofloxacin courses were given to patients with respiratory tract infection, primarily those with acute pulmonary exacerbation of cystic fibrosis. The mean daily oral dose was 25.2 mg/kg body weight. The duration of treatment ranged from one to 880 days (mean 22.8 days). Because of the arthropathogenic potential of quinolones in juvenile animals special emphasis was placed on the evaluation of musculoskeletal adverse events. Arthralgia considered by the treating physicians to be related to ciprofloxacin was reported in eight children, all of whom were females. Arthralgia resolved in all children. Some of these children were given subsequent courses of ciprofloxacin with no complaints of arthralgia. Overall, the safety profile of ciprofloxacin in children is not substantially different from that of adults.