Influenza vaccines Phenytoin

Influenza vaccine Carbamazepine Phenobarbital Phenytoin Risk of toxicity of the affected drugs effect on phenytoin inconsistent Inhibition of metabolism of the object drugs... 

Clinically important, potentially hazardous interactions with amiloride, aminoglycosides, amphotericin B, ampicillin, anisindione, anticoagulants, armodafinil, atorvastatin, azathioprine, azithromycin, bacampicillin, basiliximab, bezafibrate, bosentan, bupropion, carbenicillin, caspofungin, cholestyramine, clarithromycin, cloxacillin, co-trimoxazole, corticosteroids, cyclophosphamide, daclizumab, danazol, dicloxacillin, dicumarol, digoxin, diltiazem, disulfiram, echinacea, erythromycin, ethotoin, etoposide, ezetimibe, flunisolide, fluoxymesterone, fluvastatin, foscarnet, fosphenytoin, gemfibrozil, hemophilus B vaccine, HMG-CoA reductase inhibitors, imatinib, imipenem/cilastatin, influenza vaccines, ketoconazole, lanreotide, lopinavir, lovastatin, mephenytoin, methicillin, methoxsalen, methylphenidate, methylprednisolone, methyltestosterone, mezlocillin, mizolastine, mycophenolate, nafcillin, nisoldipine, NSAIDs, orlistat, oxacillin, penicillins, phellodendron, phenytoin, pravastatin, prednisolone, prednisone, pristinamycin, ranolazine, red rice yeast, rifabutin, rifampin, rifapentine, ritonavir, rosuvastatin, simvastatin, sirolimus, spironolactone, St John s wort, sulfacetamide, sulfadiazine, sulfamethoxazole, sulfisoxazole, sulfonamides, tacrolimus, telithromycin, tenoxicam, testosterone, ticarcillin, tolvaptan, trabectedin, triamterene, troleandomycin, ursodeoxycholic acid, vaccines, vecuronium, warfarin, zofenopril... 

Clinically important, potentially hazardous interactions with aluminum, aminophylline, aspirin, chlorambucil, cimetidine, clarithromycin, cyclophosphamide, cyclosporine, dicumarol, diuretics, docetaxel, estrogens, grapefruit juice, indomethacin, influenza vaccines, itraconazole, ketoconazole, lansoprazole, live vaccines, methotrexate, montelukast, omeprazole, oral contraceptives, pancuronium, phenobarbital, phenytoin, ranitidine, rifampicin, rifampin, timolol, tolbutamide, vitamin A... 

In yet another study, within 4 days of receiving 0.5 mL of a subvirion, trivalent influenza vaccine, the serum phenytoin levels of 7 patients were reduced by 11 to 14%, which is unlikely to have much clinical significance. A further study measured both free and total phenytoin levels in 8 patients receiving phenytoin alone. Two days after receiving 0.5 mL of a trivalent influenza vaccine, the total phenytoin level had increased by 10%, and this then returned to baseline levels by day 7. However, the free phenytoin level gradually decreased after vaccination to a maximum of 25% less at day 14. 

The efficacy of influenza vaccine is reported to be unchanged by phenytoin. ... 

Influenza vaccine i reported to increase, decrease or to have no effect on phenytoin serum levels. The efficacy of the vaccine remains unchanged. 

The serum phenytoin levels of 8 epileptic children were increased by about 50%, from 9.5 to 15.16 micrograms/mL, 7 days after they were given 0.5 mL of an influenza virus vaccine USP, types A and B, whole virus (Squibb). The phenytoin levels returned to baseline over the following 7 days. Temporary rises in the serum phenytoin levels of 3 patients, apparently caused by influenza vaccination, are briefly described in another report. ... 

In contrast, another study in 16 patients given 0.5 mL of an inactivated whole-virion trivalent influenza vaccine found that 7 and 14 days later their mean serum phenytoin levels were not significantly altered, although... 

The outcome of immunisation with influenza vaccine on phenytoin levels is uncertain. Concurrent use need not be avoided but it would be prudent to monitor the effects closely. Be aware that any alteration in levels may take a couple of weeks to develop and usually resolves spontaneously. 

Lev ine M, Jones MW, Gribble M. Increased serum phenytoin concentration followii influenza vaccination. Clin Pharm (1984) 3,505-9. 

Sawchuk RJ, Rector TS, pOTdice JJ, Leppik IE. Case report Effect of influenza vaccination on plasma phenytoin CCTicentrations. TherDrugMonit( 9T9) 1,285-8. 

Levine M, Beattie BL, McLean DM, Corman D. Phenytoin theraity and immune re nse to influenza vaccine. Clin Pharm (1985) 4, 191. ... 

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