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Included in the listing that follows are adverse reactions that have not been reported with this specific drug; however, the pharmacologic similarities among the sulfonamides require that each of the reactions be considered with Gantanol (sulfamethoxazole) administration.
Allergic Reactions: Anaphylaxis, allergic myocarditis, serum sickness, conjunctival and scleral injection, generalized allergic reactions. In addition, periarteritis nodosa and systemic lupus erythematosus have been reported.
Endocrine: The sulfonamides bear certain chemical similarities to some goitrogens, diuretics (acetazolamide and the thiazides) and oral hypoglycemic agents. Cross-sensitivity may exist with these agents. Diuresis and hypoglycemia have occurred rarely in patients receiving sulfonamides.
Read the Gantanol (sulfamethoxazole) Side Effects Center for a complete guide to possible side effects
In elderly patients concurrently receiving certain diuretics, primarily thiazides, an increased incidence of thrombopenia with purpura has been reported.
It has been reported that sulfamethoxazole may prolong the prothrombin time in patients who are receiving the anticoagulant warfarin. This interaction should be kept in mind when Gantanol (sulfamethoxazole) is given to patients already on anticoagulant therapy, and the coagulation time should be reassessed.
Sulfamethoxazole may inhibit the hepatic metabolism of phenytoin. At a 1.6-g dose, sulfamethoxazole produced a slight but significant increase in the half-life of phenytoin but did not produce a corresponding decrease in the metabolic clearance rate. When administering these drugs concurrently, one should be alert for possible excessive phenytoin effect.
Read the Gantanol Drug Interactions Center for a complete guide to possible interactions
Last reviewed on RxList: 12/8/2004
This monograph has been modified to include the generic and brand name in many instances.
Additional Gantanol Information
- Gantanol Drug Interactions Center: sulfamethoxazole oral
- Gantanol Side Effects Center
- Gantanol FDA Approved Prescribing Information including Dosage
Report Problems to the Food and Drug Administration
You are encouraged to report negative side effects of prescription drugs to the FDA. Visit the FDA MedWatch website or call 1-800-FDA-1088.
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