Mode of Action:
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.
Drug Label Information | Brands:
Brands of Sulfadiazine in Kenya
NO BRANDS IS REGISTERED BY PPB CURRENTLY
Sulfadiazine is indicated in the following conditions:
- Inclusion conjunctivitis
- 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. Sulfadiazine should be used for urinary tract infections only after use of more soluble sulfonamides has been unsuccessful.
- Malaria due to chloroquine-resistant strains of Plasmodium falciparum, when used as adjunctive therapy.
- Prophylaxis of meningococcal meningitis when sulfonamide-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.
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.
ADVERSE DRUG EFFECTS
Agranulocytosis, aplastic anemia, thrombocytopenia, leukopenia, hemolytic anemia, purpura, hypoprothrombinemia and methemoglobinemia.
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.
Nausea, emesis, abdominal pains, hepatitis, diarrhea, anorexia, pancreatitis and stomatitis.
Headache, peripheral neuritis, mental depression, convulsions, ataxia, hallucinations, tinnitus, vertigo and insomnia.
Crystalluria, stone formation, toxic nephrosis with oliguria and anuria; periarteritis nodosa and lupus erythematosus phenomenon have been noted.
The sulfonamides bear certain chemical similarities to some goitrogens, diuretics (acetazolamide and the thiazides) and oral hypoglycemic agents. Goiter production, diuresis, and hypoglycemia have occurred rarely in patients receiving sulfonamides. Cross-sensitivity may exist with these agents.
Administration of a sulfonamide may increase the effect of oral anticoagulants and methotrexate, probably by displacement of these drugs from binding sites on plasma albumin.
Potentiation of the action of sulfonylurea hypoglycemic agents, thiazide diuretics and uricosuric agents may also be noted. This may also be due to displacement of the drugs from albumin or a pharmacodynamic mechanism may play a role.
Conversely, agents such as indomethacin, probenecid and salicylates may displace sulfonamides from plasma albumin and increase the concentrations of free drug in plasma.
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/m2, 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. Maintenance, 2 g to 4 g, divided into 3 to 6 doses, every 24 hours.