Sulfadiazine tablets are indicated in the following conditions:ChancroidTrachomaInclusion conjunctivitisNocardiosisUrinary tract infections (primarily pyelonephritis, pyelitis, and cystitis) in the absence of obstructive uropathy or foreign bodies, when these infections are caused by susceptible strains of the following organisms: Escherichia coli, Klebsiella species, Enterobacter species, Staphylococcus aureus, Proteus mirabilis, and P.
Sulfadiazine should be used for urinary tract infections only after use of more soluble sulfonamides has been unsuccessful.Toxoplasmosis encephalitis in patients with and without acquired immunodeficiency syndrome, as adjunctive therapy with pyrimethamine.Malaria due to chloroquine-resistant strains of Plasmodium falciparum, when used as adjunctive therapy.Prophylaxis of meningococcal meningitis when sul fonamide-sensitive group A strains are known to prevail in family groups or larger closed populations (the prophylactic usefulness of sulfonamides when group B or C infections are prevalent is not proved and may be harmful in closed population groups).Meningococcal meningitis, when the organism has been demonstrated to be susceptible.Acute otitis media due to Haemophilus influenzae, when used concomitantly with adequate doses of penicillin.Prophylaxis against recurrences of rheumatic fever, as an alternative to penicillin.H.
influenzae meningitis, as adjunctive therapy with parental streptomycin.IMPORTANT NOTESIn vitro sulfonamide susceptibility tests are not always reliable.
The test must be carefully coordinated with bacteriologic and clinical response.
When the patient is already taking sulfonamides, follow-up cultures should have aminobenzoic acid added to the culture media.Currently, the increasing frequency of resistant organisms limits the usefulness of antibacterial agents, including the sulfonamides, especially in the treatment of recurrent and complicated urinary tract infections.Wide variation in blood levels may result with identical doses.
Blood levels should be measured in patients receiving sulfonamides for serious infections.
Free sulfonamide blood levels of 5 to 15 mg per 100 mL may be considered therapeutically effective for most infections, and blood levels of 12 to 15 mg per 100 mL may be considered optimal for serious infections.Twenty mg per 100 mL should be the maximum total sulfonamide level, since adverse reactions occur more frequently above this level.
Sulfadiazine is contraindicated in the following circumstances: Hypersensitivity to sulfonamides.In infants less than 2 months of age (except as adjunctive therapy with pyrimethamine in the treatment of congenital toxoplasmosis).In pregnancy at term and during the nursing period, because sulfonamides cross the placenta and are excreted in breast milk and may cause kernicterus.
The sulfonamides should not be used for the treatment of group A betahemolytic streptococcal infections.
In an established infection, they will not eradicate the streptococcus and, therefore, will not prevent sequelae such as rheumatic fever and glomerulonephritis.Deaths associated with the administration of sulfonamides have been reported from hypersensitivity reactions, agranulocytosis, aplastic anemia, and other blood dyscrasias.The presence of such clinical signs as sore throat, fever, pallor, purpura, or jaundice may be early indications of serious blood disorders.The frequency of renal complications is considerably lower in patients receiving the more soluble sulfonamides.