Anticoagulants with sulfonamides

Drugs that may interact with sulfonamides include oral anticoagulants, cyclosporine, hydantoins, methotrexate, and sulfonylureas. 

When a sulfonamide is administered with an oral anticoagulant, the action of the anticoagulant may be enhanced. The risk of bone marrow suppression may be increased when a sulfonamide is administered with methotrexate When a sulfonamide is administered with a hydantoin, the serum hydantoin level may be increased. 

Dicoumarol, warfarin + sulfadimethoxine, sulfamethoxypyridazine, sulfaphenazole Increased anticoagulant blood levels with risk of haemorrhage Displacement from protein by strongly bound sulfonamide Use alternative chemotherapy. Monitor patient with initiation of cessation of therapy... 

Clinically important, potentially hazardous interactions with allopurinol, anticoagulants, chloramphenicol, cyclosporine, demeclocycline, doxycycline, erythromycin, methotrexate, minocycline, oxytetracycline, sulfonamides, tetracycline... 

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 anticoagulants, antidiabetics, barbiturates, chlorpheniramine, corticosteroids, digoxin, gliclazide, lithium, methotrexate, methylphenidate, phenytoin, rifampin, sulfonamides... 

Concomitant use with anticoagulants may increase plasma levels of both drugs and, after continued therapy, may reduce the plasma levels of anticoagulant effects. Use with chloramphenicol, guanethidine, insulin, monoamine oxidase inhibitors, probenecid, salicylates, or sulfonamides may enhance the hypoglycemic effect by displacing tolazamide from its protein-binding sites. 

Important drug interactions of the sulfonamides are seen with the oral anticoagulants, the sulfony-lureas, and phenytoin. In each case, sulfonamides can potentiate the effects of the other drug, either by inhibiting its metabolism or by displacing it from albumin. Dosage adjustment may be necessary. 

Drug Interactions Contraceptive effects are decreased when "the pill" is taken with ANTIDIOTICS (ampicillin, isoniazid, neomycin, pen V, rifampin, sulfonamides, tetracycline) or CNS AGENTS (barbiturates, benzodiazepines, phenytoin). Contraceptives increase the effects of corticosteroids and worsen side effects of tricyclic antidepressants. Oral contraceptives decrease the effectiveness of oral anticoagulants, anticonvulsants, and oral hypoglycemic agents. 

Sulfonamides may adversely affect the level of some medications causing a toxic effect. Avoid using sulfonamides with anticoagulants such as coumarin or indanedione derivatives and anticonvulsants (hydantoin) as well as oral antidiabetic agents and methotrexate. 

Their application in the biomedical field is clearly demonstrated by the preponderance of patents as compared to publications in the field. Calixarenes functionalized at the wide rim with sulfonic acid and sulfonamide groups showed anticoagulant and antithrombotic properties, approaching the activity of heparin and coumarin, currently used as anticoagulants in antithrombotic therapy. Calixarene derivatives are also active as antiviral, antimicrobial. and antifungal agents. 

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