Overview
DESCRIPTION Sulfadiazine is an oral sulfonamide antibacterial agent. Sulfadiazine Tablets, USP contains 500 mg Sulfadiazine, USP. Inactive ingredients: corn starch, colloidal silicon dioxide, croscarmellose sodium, calcium stearate, lactose monohydrate, and sucrose. Sulfadiazine, USP occurs as a white or slightly yellow powder. It is odorless or nearly so and slowly darkens on exposure to light.
Mechanism of Action
CLINICAL PHARMACOLOGY The systemic sulfonamides are bacteriostatic agents having a similar spectrum of activity. Sulfonamides competitively inhibit bacterial synthesis of folic acid (pteroylglutamic acid) from aminobenzoic acid. Resistant strains are capable of utilizing folic acid precursors or preformed folic acid. Sulfonamides exist in the blood in 3 forms – free, conjugated (acetylated and possibly others) and protein bound. The free form is considered to be the therapeutically active one. Sulfadiazine given orally is readily absorbed from the gastrointestinal tract. After a single 2 g oral dose, a peak of 6.04 mg/100 mL is reached in 4 hours; of this, 4.65 mg/100 mL is free drug.
Indications
- INDICATIONS AND USAGE Sulfadiazine Tablets are indicated in the following conditions: Chancroid Trachoma Inclusion conjunctivitis Nocardiosis Urinary 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. vulgaris .
Common Doses
- 150 mg
- 4 g
- 6 g
- 500 mg
Dosage
DOSAGE AND ADMINISTRATION SYSTEMIC SULFONAMIDES ARE CONTRAINDICATED IN INFANTS UNDER 2 MONTHS OF AGE except as adjunctive therapy with pyrimethamine in the treatment of congenital toxoplasmosis. Usual Dosage for Infants over 2 Months of Age and Children Initially, one-half the 24-hour dose. Maintenance, 150 mg/kg or 4 g/m 2 , divided into 4 to 6 doses, every 24 hours, with a maximum of 6 g every 24 hours. Rheumatic fever prophylaxis, under 30 kg (66 pounds), 500 mg every 24 hours; over 30 kg (66 pounds), 1 g every 24 hours. Usual Adult Dosage Initially, 2 g to 4 g.
Contraindications
- CONTRAINDICATIONS 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.
Side Effects
- ADVERSE REACTIONS Blood Dyscrasias Agranulocytosis, aplastic anemia, thrombocytopenia, leukopenia, hemolytic anemia, purpura, hypoprothrombinemia and methemoglobinemia. Allergic Reactions Erythema multiforme (Stevens-Johnson syndrome), generalized skin eruptions, epidermal necrolysis, urticaria, serum sickness, pruritus, exfoliative dermatitis, anaphylactoid reactions, periorbital edema, conjunctival and scleral injection, photosensitization, arthralgia, allergic myocarditis, drug fever and chills.
Interactions
- No major interactions listed on the FDA label. Always consult a healthcare professional.