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Query: UMLS:C0012833 (dizziness)
 9,689 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

1. The safety in everyday clinical usage of three 4-quinolone antibiotics, (ciprofloxacin, norfloxacin and ofloxacin), was compared with similar data for azithromycin and cefixime, each agent being examined by Prescription-Event Monitoring (PEM) during the early post-marketing period. 2. In PEM the exposure data are derived from general practitioner prescriptions confidentially provided by the Prescription Pricing Authority. Outcome data are provided by questionnaires (green forms) on which the prescribing medical practitioner records event data. When necessary, further information is obtained from a number of sources which include follow-up of all pregnancies and the patients' life-time medical record. 3. The main outcome measures were demographic information, including the patient's date of birth and sex; the indication for prescribing the drug being monitored; the reason for stopping treatment; the start and stop dates of treatment and the events recorded during and after treatment. 4. The final cohort for each of the five antibiotics exceeded 11000 patients. The only event significantly related to the use of all five antibiotics was nausea/vomiting. This was also the most frequent adverse event causing treatment to be discontinued with norfloxacin, ofloxacin and azithromycin (relevant information was not requested in the studies of ciprofloxacin and cefixime). Vaginal candidiasis was significantly more frequently associated with the use of the three 4-quinolones than with azithromycin and cefixime but it was frequently delayed until the week or two after the cessation of therapy. Within each event, as recorded in these studies, the highest event rates (the number of events per 1000 patients) in the week following the start of therapy were: 9.2 for diarrhoea with cefixime; 4.9 for nausea/vomiting with ofloxacin; 2.4 for rash with azithromycin; 2.2 for abdominal pain with norfloxacin; 1.5 for headache/migraine with ofloxacin; 1.4 for malaise/lassitude with ofloxacin; 1.2 for dizziness with norfloxacin. Uncommon events (reported in less than 1:1000 patients) included rare cases of allergic phenomena, convulsions and pseudomembranous colitis. There were no reports of tendinitis, tenosynovitis or tendon rupture in children but tendon disorders were reported in the two months following the start of treatment in 20 adults. A total of 307 pregnancies were reported. Thirty-eight of the 55 women who received these drugs during the first trimester of pregnancy gave birth to healthy babies. No congenital abnormalities were reported. Apart from one case of unconfirmed pseudomembranous colitis, none of the other 2468 deaths that occurred in these studies was attributed to the antibiotics. 5. These five antibiotics are acceptably safe antimicrobial agents when used in general medical practice. PEM is an effective method for monitoring the safety of recently introduced antimicrobial agents.
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PMID:A comparison of ciprofloxacin, norfloxacin, ofloxacin, azithromycin and cefixime examined by observational cohort studies. 873 Sep 72

For 2 decades fluoroquinolones have been found to be generally well-tolerated and safe. Adverse events may be inherent to the class or influenced by structural modifications. The commonest adverse events are gastrointestinal tract (GI) and central nervous system (CNS) reactions; nephrotoxicity and tendinitis are infrequent, but agents differ greatly in phototoxic potential. Fluoroquinolones are safe in elderly, human immunodeficiency virus-infected, and neutropenic patients, but because of possible effects on articular cartilage, they are not currently recommended for children or pregnant women. Four new agents have recently been licensed. Levofloxacin causes few GI or CNS adverse events and is minimally phototoxic. Sparfloxacin infrequently causes GI or CNS effects but is associated with relatively high rates of phototoxicity and prolongation of the electrocardiographic QTc interval (Q-T interval, corrected for heart rate). Grepafloxacin causes relatively high rates of GI effects, taste perversion, and QTc interval prolongation, but it is minimally phototoxic. Trovafloxacin is associated with a moderate rate of GI effects and a relatively high incidence of dizziness but has low phototoxic potential.
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PMID:Fluoroquinolone toxicity profiles: a review focusing on newer agents. 1006 55

Reactions of the gastrointestinal tract, the CNS and the skin are the most often observed adverse effects during therapy with fluoroquinolones. At least for some of the newer fluoroquinolones a steep dose-response relationship of adverse effects seems to exist. Pathogenesis of the neurotoxic effects of fluoroquinolones is still unknown. Among the newer drugs, trovafloxacin caused mild CNS reactions such as dizziness and lightheadedness in a considerable proportion of patients. Young females seem to be especially sensitive to this effect, which diminishes during treatment or if taken together with food. Cardiotoxic potentials of sparfloxacin and grepafloxacin are higher than those of other fluoroquinolones, but during therapy no clearcut drug-related serious reactions have been reported, apart from a slight prolongation of the QT interval. However, to avoid risks these drugs should not be prescribed to patients with known prolongation of the QT interval (e.g. patients on antiarrhythmics). Phototoxicity has been described for all quinolones, but derivatives with a halogen atom at position 8 show the highest potential for such reactions. Fleroxacin, sparfloxacin, clinafloxacin and lomefloxacin belong to this group of fluoroquinolones. The phototoxic potential of the other new fluoroquinolones is considerably lower, but extensive exposure to UV light should generally be avoided during therapy with all quinolones. Chondrotoxicity of quinolones, as observed in immature animals, can affect articular cartilage and/or the epiphyseal growth plate, depending on the developmental stage. Pathogenesis of chondrotoxicity can probably be explained by the magnesium-chelating properties of these drugs. As juveniles are especially sensitive, use of these drugs in paediatrics should be restricted to carefully selected indications (such as the use of ciprofloxacin in cystic fibrosis). Another manifestation of the toxic effects of quinolones on connective tissue structures are tendopathies. Tendinitis and tendon ruptures have occurred as late as several months after quinolone treatment. Overall, quinolones are well tolerated drugs. Their specific toxic potentials have to be considered when they are chosen for treatment of bacterial infections.
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PMID:Toxicity of quinolones. 1055 3

The most common adverse effects of the fluoroquinolones involve the gastrointestinal tract, skin and CNS, and are mainly mild and reversible. Of the gastrointestinal events, nausea and vomiting are the most common. Mild hepatic reactions are a class effect, usually presenting as mild transaminase level increases without clinical symptoms. However, postmarketing surveillance has revealed significant hepatotoxicity with trovafloxacin. It is not currently known whether the severe reactions to trovafloxacin are specific to that agent or simply represent an extreme of an emerging class effect. The enormous worldwide usage of, and extensive published adverse effect data on the other fluoroquinolones and naphthyridones suggests the former. In perspective, rare but serious hepatotoxicity has been reported with other fluoroquinolones and the overall incidence of trovafloxacin hepatotoxicity is not dissimilar to that reported with flucloxacillin and amoxicillin-clavulanic acid. CNS reactions vary in severity and include dizziness, convulsions (notably with lomefloxacin) and psychoses. Fluoroquinolones differ in their pro-convulsive activity, relating to their differing potential as gamma-aminobutyric acid antagonists and binding to the N-methyl-D-aspartate receptor. The basis for the increased seizure potential following the coadministration of nonsteroidal anti-inflammatory drugs with certain fluoroquinolones is not fully understood. Fluoroquinolone phototoxicity, caused by the generation of toxic free oxygen species under exposure to UVA radiation, is significantly more common with 8-halogenated compounds. Certain patient groups, e.g. patients with cystic fibrosis, are predisposed to this adverse effect. Murine photocarcinogenicity has been demonstrated with lomefloxacin, but no such effects have been reported in humans. Prolongation of the QTc interval is also a class effect, although cardiac arrhythmias have only been linked with sparfloxacin. Among the newer fluoroquinolones, clinically significant cardiac events are rare or absent but possible interactions in patients receiving other drugs capable of causi ng QT prolongation should be anticipated. Tendinitis and rupture, usually of the Achilles tendon, are rare, class-effects of fluoroquinolones, most frequently reported with pefloxacin. Predisposing factors include aging, corticosteroid use, renal disease, haemodialysis and transplantation. Use of fluoroquinolones in paediatric patients remains contentious. However, accruing human data suggest that restrictions on paediatric use imposed because of fluoroquinolone-induced cartilage damage in juvenile animals, may soon be relaxed. Data from over 1700 children in the UK failed to disclose arthropathy and extensive paediatric use of norfloxacin in Japan and ciprofloxacin in developing countries has been free of articular effects.
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PMID:Comparative tolerability of the newer fluoroquinolone antibacterials. 1055 54

Significant safety issues that have arisen with fluoroquinolones include phototoxicity, cardiotoxicity, tendinitis, CNS effects and drug interactions. Ciprofloxacin is well tolerated; the incidence of adverse events is low and serious adverse events are rare. Levofloxacin has a reduced CNS adverse event rate compared with ofloxacin. Sparfloxacin has significant phototoxicity and potential cardiac toxicity. Grepafloxacin has significantly increased adverse event rates, particularly gastrointestinal intolerance. Taste perversion and nausea are common. Trovafloxacin has an increased potential for CNS adverse reactions, notably dizziness. Post-marketing surveillance data indicate the possibility of serious hepatic reactions and pancreatitis. Interactions between fluoroquinolones and drugs metabolised by the hepatic cytochrome P450 system affect the clearance of theophylline and caffeine. Quinolone absorption is significantly reduced by co-administration of antacids. Hospitalised patients are likely to be receiving multiple-drug therapy, but drug interactions are avoidable. The interactions of specific fluoroquinolones should be checked prior to prescription.
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PMID:Safety of the new fluoroquinolones compared with ciprofloxacin. 1141 83

Fluoroquinolones are the commonly used antimicrobials in the treatment of urinary tract infection, bacterial diarrhea, and infections of soft tissue, bone, and joints. They may cause adverse effects ranging from gastrointestinal disturbances, headache, insomnia, and cutaneous reactions. Their rare adverse effects include phototoxicity, cardiotoxicity, arthropathy, and tendinitis. Among the fluoroquinolones, levofloxacin has more propensity to cause the central nervous system adverse effects such as headache, tremor, insomnia, dizziness, convulsions, psychosis, auditory, and visual hallucinations. A case of acute sinusitis in a young male treated with levofloxacin presented with tactile hallucination and acute anxiety reaction is reported for its rarity of occurrence. According to the Naranjo causality scale, the association of tactile hallucination and acute anxiety is a probable adverse drug reaction due to levofloxacin.
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PMID:Levofloxacin-induced tactile hallucination and acute anxiety reaction. 3114 49