Susceptible infections
Adult: As sulfadiazine 167 mg, sulfadimidine 167 mg, sulfamerazine 167 mg combination per tablet:  Initially 4-8 tablets, then 2 tablets every 6 hr.
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Indications and Dosage
                                             
                                            
Oral 
                                        Susceptible infections Adult: As sulfadiazine 167 mg, sulfadimidine 167 mg, sulfamerazine 167 mg combination per tablet:  Initially 4-8 tablets, then 2 tablets every 6 hr. 
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Renal Impairment
                                             
                                            
Dose reduction may be needed.
                                             
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Hepatic Impairment
                                             
                                            
Dose reduction may be needed.
                                             
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Contraindications
                                             
                                            
Severe renal or hepatic failure; blood disorders; hypersensitivity to sulfonamides; acute porphyria; SLE. Pregnancy and lactation; infants ≤2 mth.
                                             
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Special Precautions
                                             
                                            
Renal or hepatic impairment; history of allergy or asthma; AIDS; G6PD deficiency (at risk of hemolytic reactions); elderly; ensure adequate fluid intake to reduce risk of crystalluria. Discontinue use if rash develops.
                                             
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Adverse Reactions
                                             
                                            
Nausea, vomiting, anorexia, diarrhoea, hypersensitivity reactions, SLE, serum sickness-like syndrome, liver necrosis and hepatomegaly, myocarditis, pulmonary eosinophilia and fibrosing alveolitis, vasculitis, hypoglycaemia, hypothyroidism, neurological reactions, jaundice and kernicterus in premature neonates. Pseudomembranous colitis. 
                                        Potentially Fatal: Blood dyscrasias, Stevens-Johnson Syndrome, toxic epidermal necrolysis, anaphylaxis.  | 
                                
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Drug Interactions
                                             
                                            
Potentiates effects of oral anticoagulants, methotrexate, phenytoin. Increased risk of crystalluria by compounds that render the urine acidic. 
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Lab Interference
                                             
                                            
Interference with tests for urea, creatinine, urinary glucose and urobilinogen.
                                             
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Action
                                             
                                            
Description:  
                                        Mechanism of Action: Sulfamerazine is a short-acting sulfonamide that interferes with the synthesis of nucleic acids in sensitive organisms by blocking the conversion of p-aminobenzoic acid (PABA) to the co-enzyme dihydrofolic acid. Its action is bacteriostatic, bactericidal effect may be exerted where concentrations of thymine are low in the surrounding medium. It is usually administered with other sulfonamides or with trimethoprim.  | 
                                
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MIMS Class
                                             
                                            
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