Phenytoin Ciprofloxacin

Cimetidine Phenytoin Ciprofloxacin Ranitidine Digoxin Tetracycline Norfloxacin Theophylline... 

PHENYTOIN CIPROFLOXACIN Variable effect on phenytoin levels Unknown Monitor phenytoin levels... 

Few serious interactions, but discuss with pharmacy if SSRls, carbamazepine, phenytoin, ciprofloxacin, erythromycin, chemotherapy or depot antipsychotics... 

In patients allergic to penicillin, macrolides are usually indicated in mild respiratory tract infections. Zithromax contains azithromycin, which is a macrolide that may be indicated for respiratory tract infections. As opposed to clarithromycin (another macrolide), azithromycin does not present any significant clinical interaction with phenytoin. Ciproxin contains ciprofloxacin. 

Theophylline is a narrow therapeutic index drug with significant difference in bioavailability following oral administration. The half-life of the drug is increased by heart failure, cirrhosis and viral infections, in elderly patients, and by certain drugs, such as cimetidine, ciprofloxacin, oral contraceptives and fluvoxamine. The half-life is decreased in smokers, chronic alcoholism, and by certain drugs, such as phenytoin, rifampicin and carbamazepine. 

Drugs that may affect cyclosporine include allopurinol, amiodarone, androgens (eg, danazol, methyltestosterone), anticonvulsants (eg, carbamazepine, phenobarbital, phenytoin), azole antifungals (eg, fluconazole, ketoconazole), beta-blockers, bosentan, bromocriptine, calcium channel blockers, colchicine, oral contraceptives, corticosteroids, fluoroquinolones (eg, ciprofloxacin), foscarnet, HMG-CoA reductase inhibitors, imipenem-cilastatin, macrolide antibiotics, methotrexate, metoclopramide, nafcillin, nefazodone, orlistat, potassium-sparing diuretics, probucol, rifamycins (rifampin, rifabutin), serotonin reuptake inhibitors (SSRIs eg, fluoxetine, sertraline),... 

Ciprofloxacin (Cipro, Cipro XR, Proquin XR) [Antibiotic/ Fluoroquinolone] Uses Rx lower resp tract, sinuses, skin skin structure, bone/joints, urinary tract Infxns including prostatitis Action Quinolone antibiotic DNA gyrase Dose Adults. 250-750 mg PO ql2h XR 500-1000 mg PO q24h or 200-400 mg IV ql2h in renal impair Caution [C, /-] Children <18 y Contra Component sensitivity Disp Tabs, susp, inj SE Restlessness, N/V/D, rash, ruptured tendons, T LFTs Interactions T Effects Wf probenecid T effects OF diazepam, theophylline, caffeine, metoprolol, propranolol, phenytoin, warfarin effects W/ antacids, didanosine, Fe salts. Mg, sucralfate, Na bicarbonate,... 

Others Acetaminophen, amiodarone, carbamazepine, delavirdine, efavirenz, nevirapine, quinidine, repaglinide, sildenafil, tadalafil, trazodone, vardenafil Amiodarone, amprenavir, atazanavir, ciprofloxacin, cisapride, clarithromycin, diltiozem, erythromycin, fluconazole, fluvoxamine, grapefruit juice (in high ingestion), indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, norfloxacin, ritonavir, telithromycin, troleandomycin, verapamil, voriconazole Carbamazepine, efavirenz, glucocorticoids, macrolide antibiotics, nevirapine, phenytoin, phenobarbital, rifabutin, rifapentine, rifampin, St. John s wort... 

L E. Quinidine. These are the classic signs of cinchon-ism and are adverse effects of quinidine and quinine, constituents of the cinchona tree. Some of these effects could be seen as toxic effects of phenytoin. However, auditory acuity is associated with cinchonism and not with phenytoin toxicity. Nausea but not the other effects could be associated with ciprofloxacin. Excessive drowsiness would be expected if diazepam were involved. These effects would not be expected with the estrogen replacement therapy. 

All quinolones interact with multivalent cations, forming chelation complexes resulting in reduced absorption. Major offenders are antacids vitamins containing calcium and iron can also be problematic. All fluoroquinolones interact with warfarin, didanosine (ddi), and phenytoin, resulting in decreased absorption or metabolism. Ciprofloxacin and other second-generation drugs interact with theophylline by decreasing its clearance, which leads to theophylline toxicity. 

Ciprofloxacin Phenytoin Reduced effect of phenytoin Unknown... 

Ciprofloxacin may interact with phenytoin reducing phenytoin concentrations (77). 

A lower than expected phenytoin serum concentration has been measured in a 78-year-old white woman with a grade III astrocytoma of the right parieto-occipital region treated with ciprofloxacin (500 mg bd) (78). 

Otero MJ, Moran D, Valverde MP. Interaction between phenytoin and ciprofloxacin. Ann Pharmacother 1999 33(2) 251-2. 

McLeod R, Trinkle R. Comment unexpectedly low phenytoin concentration in a patient receiving ciprofloxacin. Ann Pharmacother 1998 32(10) 1110-11. 

Allergic interstitial nephritis Penicillins, rifampin, sulfonamides, thiazides, cimetidine.phenytoin, allopurinol, furosemide, NSAIDS, ciprofloxacin, pantoprazole, omeprazole, atazanavir, bevacizumab Rash, fever, eosinophilia, eosinophiluria, pyuria... 

Clinically important, potentially hazardous interactions with ciprofloxacin, clorazepate, ketoconazole, lansoprazole, lomefloxacin, phenytoin, sparfloxacin, tetracycline... 

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