Ciprofloxacin¿¡ ´ëÇÑ Mechanism_Of_Action Á¤º¸ 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, and recombination. Dexamethasone¿¡ ´ëÇÑ Mechanism_Of_Action Á¤º¸ Dexamethasone is a glucocorticoid agonist. Unbound dexamethasone crosses cell membranes and binds with high affinity to specific cytoplasmic receptors. This results in a modification of transcription and, hence, protein synthesis in order to achieve inhibition of leukocyte infiltration at the site of inflammation, interference in the function of mediators of inflammatory response, suppression of humoral immune responses, and reduction in edema or scar tissue. The antiinflammatory actions of dexamethasone are thought to involve phospholipase A2 inhibitory proteins, lipocortins, which control the biosynthesis of potent mediators of inflammation such as prostaglandins and leukotrienes.
Pharmacology
Ciprofloxacin¿¡ ´ëÇÑ Pharmacology Á¤º¸ 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. Dexamethasone¿¡ ´ëÇÑ Pharmacology Á¤º¸ Dexamethasone and its derivatives, dexamethasone sodium phosphate and dexamethasone acetate, are synthetic glucocorticoids. Used for its antiinflammatory or immunosuppressive properties and ability to penetrate the CNS, dexamethasone is used alone to manage cerebral edema and with tobramycin to treat corticosteroid-responsive inflammatory ocular conditions.
Ciprofloxacin¿¡ ´ëÇÑ Absorption Á¤º¸ 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. Dexamethasone¿¡ ´ëÇÑ Absorption Á¤º¸ 80-90%
Ciprofloxacin¿¡ ´ëÇÑ Biotransformation Á¤º¸ 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. Dexamethasone¿¡ ´ëÇÑ Biotransformation Á¤º¸ Hepatic.
Toxicity
Ciprofloxacin¿¡ ´ëÇÑ Toxicity Á¤º¸ The major adverse effect seen with use of is gastrointestinal irritation, common with many antibiotics. Dexamethasone¿¡ ´ëÇÑ Toxicity Á¤º¸ Oral, rat LD50: >3 gm/kg. Signs of overdose include retinal toxicity, glaucoma, subcapsular cataract, gastrointestinal bleeding, pancreatitis, aseptic bone necrosis, osteoporosis, myopathies, obesity, edemas, hypertension, proteinuria, diabetes, sleep disturbances, psychiatric syndromes, delayed wound healing, atrophy and fragility of the skin, ecchymosis, and pseudotumor cerebri.
Drug Interactions
Ciprofloxacin¿¡ ´ëÇÑ Drug_Interactions Á¤º¸ Aluminium Formation of non-absorbable complexesMethotrexate Increases methotrexate toxicity Aminophylline The quinolone increases the effect of theophyllineAnisindione The quinolone increases the anticoagulant effectBismuth Formation of non-absorbable complexesCaffeine The quinolone increases the effect and toxicity of caffeineCalcium Formation of non-absorbable complexesClozapine Ciprofloxacin may increase clozapine serum levelsCyclosporine The quinolone increases the effect and toxicity of cyclosporineDicumarol The quinolone increases the anticoagulant effectDihydroxyaluminium Formation of non-absorbable complexesDyphylline The quinolone increases the effect of theophyllineDuloxetine Increases the effect/toxicity of duloxetineDyphylline The quinolone increases the effect of theophyllineEthotoin Decreases the hydantoin effectFoscarnet Increased risk of convulsionsFosphenytoin Decreases the hydantoin effectMagnesium oxide Formation of non-absorbable complexesMagnesium Formation of non-absorbable complexesMephenytoin Decreases the hydantoin effectAcenocoumarol The quinolone increases the anticoagulant effectOxtriphylline The quinolone increases the effect of theophyllinePhenytoin Decreases the hydantoin effectProcainamide The quinolone increases the effect of procainamideRasagiline Increases effect/toxicity of rasagilineRopinirole The quinolone increases the effect and toxicity of ropiniroleSevelamer Sevelamer decreases ciprofloxacin bioavailabilitySildenafil The quinolone increases sildenafil levelsSucralfate Formation of non-absorbable complexesTheophylline The quinolone increases the effect of theophyllineTizanidine Increases the effect/toxicity of tizanidineWarfarin The quinolone increases the anticoagulant effectIron Formation of non-absorbable complexesZinc Formation of non-absorbable complexes Dexamethasone¿¡ ´ëÇÑ Drug_Interactions Á¤º¸ Ambenonium The corticosteroid decreases the effect of anticholinesterasesAminoglutethimide Aminogluthetimide decreases the effect of dexamethasoneAmobarbital The barbiturate decreases the effect of the corticosteroidAnisindione The corticosteroid alters the anticoagulant effectAprepitant Aprepitant increases the effect and toxicity of dexamethasoneAprobarbital The barbiturate decreases the effect of the corticosteroidAspirin The corticosteroid decreases the effect of salicylatesButabarbital The barbiturate decreases the effect of the corticosteroidButalbital The barbiturate decreases the effect of the corticosteroidButethal The barbiturate decreases the effect of the corticosteroidDicumarol The corticosteroid alters the anticoagulant effectDihydroquinidine barbiturate The barbiturate decreases the effect of the corticosteroidEdrophonium The corticosteroid decreases the effect of anticholinesterasesEthotoin The enzyme inducer decreases the effect of the corticosteroidFosphenytoin The enzyme inducer decreases the effect of the corticosteroidHeptabarbital The barbiturate decreases the effect of the corticosteroidHexobarbital The barbiturate decreases the effect of the corticosteroidImatinib Decreases levels of imatinibMephenytoin The enzyme inducer decreases the effect of the corticosteroidMethohexital The barbiturate decreases the effect of the corticosteroidMethylphenobarbital The barbiturate decreases the effect of the corticosteroidMidodrine Increased arterial pressureNeostigmine The corticosteroid decreases the effect of anticholinesterasesPentobarbital The barbiturate decreases the effect of the corticosteroidPhenobarbital The barbiturate decreases the effect of the corticosteroidPhenytoin The enzyme inducer decreases the effect of the corticosteroidPrimidone The barbiturate decreases the effect of the corticosteroidPyridostigmine The corticosteroid decreases the effect of anticholinesterasesQuinidine barbiturate The barbiturate decreases the effect of the corticosteroidRifampin The enzyme inducer decreases the effect of the corticosteroidSecobarbital The barbiturate decreases the effect of the corticosteroidSunitinib Possible decrease in sunitinib levelsTalbutal The barbiturate decreases the effect of the corticosteroidWarfarin The corticosteroid alters the anticoagulant effectBismuth The corticosteroid decreases the effect of salicylatesAcenocoumarol The corticosteroid alters the anticoagulant effectSalicylate-magnesium The corticosteroid decreases the effect of salicylatesSalsalate The corticosteroid decreases the effect of salicylates