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any of a group of synthetic antibacterial agents that includes cinoxacin, ciprofloxacin, nalidixic acid, norfloxacin, and ofloxacin.


/quin·o·lone/ (kwin´o-lōn) any of a group of synthetic antibacterial agents that includes nalidixic acid and the fluoroquinolones.


Any of a class of synthetic broad-spectrum antibacterial drugs derived from quinoline compounds.


any of a class of antibiotics that act by interrupting the replication of deoxyribonucleic acid (DNA) molecules in bacteria. The action involves inhibition of the bacteria's gyrase so that positively supercoiled DNA cannot be relaxed for DNA transcription and replication. An example is ciprofloxacin.

anabolic steroid

A drug or hormone-like substance chemically or pharmacologically related to 17-α-alkylated testosterone that promotes muscle growth, which are commonly abused by athletes. Lipid changes by ASs are more marked with oral stanazol (manufactured for horses) than with IV testosterone; it decreases HDL-C (especially HDL2) and increases hepatic TG lipase (HDL) catabolism.
Children, adolescents with delayed puberty, decreased growth, small penis, hypogonadism, testosterone deficiency, osteoporosis management, aplastic anaemia, endometriosis, angioedema, sports performance enhancement (no longer legal), relief and recovery from common injuries, rehabilitation, weight control, anti-insomnia, and regulation of sexuality, aggression and cognition.

Oral, parenteral.
Metabolic effects
Increased protein synthesis and amino acid consumption, androgenesis, catabolism and gluticocototitosis.
Adverse effects (men)
Breast enlargement (gynecomastia), testicular atrophy, sterility, sperm abnormalities, impotence, prostatic hypertrophy, myocardial hypertrophy and fibrosis, myocardial infarction and fatal arrhythmias, peliosis hepatis, cholestasis, hepatic adenomas, testicular atrophy, peripheral oedema, intracerebral thrombosis.

Adverse effects (women)
Clitoral hypertrophy, beard growth, baldness, deepened voice, decreased breast size.

Adverse effects (men and women)
Aggression and antisocial behavior, increased risk of cardiovascular disease, peliosis hepatis, haemorrhage, jaundice, acne, accelerated bone maturation resulting in short stature, liver tumours (hepatic adenomas and CA) which may regress with abstinence; AS abusers are at an increased risk for HIV transmission, given the common practice of sharing of needles when injecting ASs.

ASs are detectable to 1 parts per billion 4 days after last use if the hormone is water-soluble, or 14 days after use in lipid-soluble compounds.

FDA status
ASs are schedule-III drugs per the Controlled Substances Act.


Fluoroquinolone Infectious disease Any of a family of broad-spectrum oral antibiotics–eg, ciprofloxacin, norfloxacin, and ofloxicin, which target bacterial DNA gyrase and concentration-dependent inhibitors of DNA synthesis; bacterial resistance to quinolones is rare and hinges on mutations of gyrase; quinolones are active against most aerobes, including bacteria resistant to other antibiotics; they are effective in GI, GU, prostatic, respiratory infections, STDs Adverse effects GI discomfort, vague CNS Sx

quinolone (kwin´əlōn´),

n a class of antibiotics that act by interrupting the replication of deoxyribonucleic acid molecules in bacteria.
References in periodicals archive ?
This study searched to verify the possible presence of antibiotic residues in pasteurized and unpasteurized milk, produced and marketed in the microregion of Capanema, State of Parana, Brazil, through qualitative screening methods for detection of four different groups of drugs, [beta]-lactams, tetracyclines, quinolones and sulfonamides, to map the status of the chemical milk quality in respect of contamination by antibiotic residues.
Volume ratio between quinolone and coal tar was 20: 1 and the static time was 24 h.
The rate of resistance to TMP/SMX was up to 27 (18%) and this rate for quinolone family was: ciprofloxacin 27 (18%), gatifloxacin 24 (16%), moxifloxacin 25 (17%), and ofloxacin 30 (20%).
The combination of rifampin, doxycycline, and streptomycin often is used whereas in non-responded or complicated cases, quinolones could be added to the conventional treatment as a third agent (Falagas and Bliziotis, 2006).
The second is plasmid-mediated resistance, which results from extrachromosomal elements that encode proteins that disrupt quinoloneenzyme interactions, alter drug metabolism, or increase quinolone efflux.
Quinolones in treatment of human brucellosis: comparative tria of ofloxacin-rifampin versus doxycycline-rifampin.
Plasmid-mediated quinolone resistance determinants qnr and aac(6')-Ib-cr in Escherichia coli and Klebsiella spp.
Quinolone is a group of antibiotic which acts by inhibiting enzymatic activities of two members of the topoisomerase class of enzymes, DNA gyrase and topoisomerase IV.
8 million inpatients who received an injectable quinolone in 2011.
The new drug class identified by the researchers were derived from the first antimalarial quinolone, endochin, discovered more than 60 years ago but never pursued as a treatment because it appeared not to work in humans.
The findings "reinforce what our gut instincts have been saying about prescribing for cystitis: Physicians are having more concerns about resistance and are therefore going to the second-line agents like quinolones, cephalosporins, and other medications," Jessina C.