indication

For the treatment of the following infections caused by susceptible organisms: urinary tract infections, acute uncomplicated cystitis, chronic bacterial prostatitis, lower respiratory tract infections, acute sinusitis, skin and skin structure infections, bone and joint infections, complicated intra-abdominal infections (used in combination with metronidazole), infectious diarrhea, typhoid fever (enteric fever), uncomplicated cervical and urethral gonorrhea, and inhalational anthrax (post-exposure).

pharmacology

Ciprofloxacin is a broad-spectrum antiinfective agent of the fluoroquinolone class. Ciprofloxacin has in vitro activity against a wide range of gram-negative and gram-positive microorganisms. The mechanism of action of quinolones, including ciprofloxacin, is different from that of other antimicrobial agents such as beta-lactams, macrolides, tetracyclines, or aminoglycosides; therefore, organisms resistant to these drugs may be susceptible to ciprofloxacin. There is no known cross-resistance between ciprofloxacin and other classes of antimicrobials. Notably the drug has 100 times higher affinity for bacterial DNA gyrase than for mammalian.

mechanism of action

The bactericidal action of ciprofloxacin results from inhibition of the enzymes topoisomerase II (DNA gyrase) and topoisomerase IV, which are required for bacterial DNA replication, transcription, repair, strand supercoiling repair, and recombination.

toxicity

The major adverse effect seen with use of is gastrointestinal irritation, common with many antibiotics.

biotransformation

Hepatic. Four metabolites have been identified in human urine which together account for approximately 15% of an oral dose. The metabolites have antimicrobial activity, but are less active than unchanged ciprofloxacin.

absorption

Rapidly and well absorbed from the gastrointestinal tract after oral administration. The absolute bioavailability is approximately 70% with no substantial loss by first pass metabolism.

half life

4 hours

route of elimination

Approximately 40 to 50% of an orally administered dose is excreted in the urine as unchanged drug.

drug interactions

Acenocoumarol: The quinolone antibiotic, ciprofloxacin, may increase the anticoagulant effect of acenocoumarol.

Aluminium: Formation of non-absorbable complexes

Aminophylline: Ciprofloxacin may increase the effect of aminophylline.

Anisindione: The quinolone antibiotic, ciprofloxacin, may increase the anticoagulant effect of anisindione.

Caffeine: Ciprofloxacin may increase the effect and toxicity of caffeine.

Calcium: Formation of non-absorbable complexes

Calcium Acetate: Calcium salts such as calcium acetate may decrease the absorption of quinolone antibiotics such as ciprofloxacin. Of concern only with oral administration of both agents. Interactions can be minimized by administering oral quinolone at least 2 hours before, or 6 hours after, the dose of an oral calcium supplement. Monitor for decreased therapeutic effects of oral quinolones if administered with oral calcium supplements.

Clozapine: Ciprofloxacin may increase clozapine serum levels

Cyclosporine: Ciprofloxacin may increase the effect and toxicity of cyclosporine.

Dicumarol: The quinolone antibiotic, ciprofloxacin, may increase the anticoagulant effect of dicumarol.

Dihydroxyaluminium: Formation of non-absorbable complexes

Duloxetine: Ciprofloxacin, a strong CYP1A2 inhibitor, may decrease the metabolism of duloxetine. Monitor for changes in the therapeutic and adverse effects of duloxetine if ciprofloxacin is initiated or discontinued.

Dyphylline: Ciprofloxacin may increase the effect of dyphylline.

Ethotoin: Decreases the hydantoin effect

Foscarnet: Increased risk of convulsions

Iron: Formation of non-absorbable complexes

Iron Dextran: Formation of non-absorbable complexes

Magnesium: Formation of non-absorbable complexes

Magnesium oxide: Formation of non-absorbable complexes

Mephenytoin: Decreases the hydantoin effect

Methotrexate: Ciprofloxacine may decrease the metabolism of methotrexate. Monitor for changes adverse effects of methotrexate if ciprofloxacin is initiated.

Oxtriphylline: Ciprofloxacin may increase the effect of oxtriphylline.

Phenytoin: Ciprofloxacin may decrease the therapeutic effect of phenytoin.

Procainamide: Ciprofloxacin may increase the effect of procainamide.

Ramelteon: Ciprofloxacin increases levels/toxicity of ramelteon

Rasagiline: Ciprofloxacin, a strong CYP1A2 inhibitor, may decrease the metabolism of rasagiline. Monitor for changes in the therapeutic and adverse effects of rasagiline if ciprofloxacin is initiated or discontinued.

Ropinirole: Ciprofloxacin may increase the effect and toxicity of ropinirole.

Sevelamer: Sevelamer decreases ciprofloxacin bioavailability

Sildenafil: Ciprofloxacin may increase the serum level of sildenafil.

Sucralfate: Formation of non-absorbable complexes

Tacrine: The metabolism of Tacrine, a CYP1A2 substrate, may be reduced by strong CYP1A2 inhibitors such as Ciprofloxacin. Consider modifying therapy to avoid Tacrine toxicity. Monitor the efficacy and toxicity of Tacrine if Ciprofloxacin is initiated, discontinued or if the dose is changed.

Theophylline: Ciprofloxacin may increase the effect of theophylline.

Thiothixene: The strong CYP1A2 inhibitor, Ciprofloxacin, may decrease the metabolism and clearance of Thiothixene, a CYP1A2 substrate. Consider alternate therapy or monitor for changes in Thiothixene therapeutic and adverse effects if Ciprofloxacin is initiated, discontinued or dose changed.

Tizanidine: Ciprofloxacin inhibits the metabolism and clearance of Tizanidine. Concomitant therapy is contraindicated.

Warfarin: The quinolone antibiotic, ciprofloxacin, may increase the anticoagulant effect of warfarin.

Zinc: Formation of non-absorbable complexes