The Cathay Drug Co., Inc.
Each gram of cream contains micronized silver sulfadiazine 1 mg.
Silver sulfadiazine has broad antimicrobial activity against Gram-positive and Gram-negative bacteria including Pseudomonas aeruginosa, and some yeasts and fungi. Silver sulfadiazine has a bactericidal action, in contrast to sulfadiazine, the silver salt acts primarily on the cell membrane and cell wall and its action is not antagonized by p-aminobenzoic acid (PABA).
Silver sulfadiazine slowly releases sulfadiazine when in contact with wound exudates. Up to about 10% of the sulfadiazine may be absorbed; concentrations in blood of 10 to 20 mcg per mL have been reported, although higher concentrations may be achieved when extensive areas of the body are treated. Some silver may also be absorbed.
Silver sulfadiazine (SILVEDERMA) cream is an antimicrobial agent for topical use. It is a sulfonamide that is used, in conjunction with debridement, as a 1% cream for the prevention and treatment of infection in severe burns.
DOSAGE AND ADMINNISTRATION
The size of the burn is determined by the body-surface area affected. Measurement is performed in multiples of nine.
|BODY PART||SIZE OF BURN|
For children below 8 years old:
Measure the burn size by assuming the palm of the child’s hand is approximately 1 % of their body surface area, then estimate the number of “hands” needed to cover the burn.
Adults and children 2 months of age and older:
After cleaning and debridement of wound, apply the cream with a sterile gloved hand, to the burned surface with a thickness of 1 to 3 mm, assuring that all crevices of the irregular burn surface are treated.
The cream is usually applied once or twice daily to a thickness of approximately 1/16 inch (1.5 mm). However, silver sulfadiazine (SILVEDERMA) cream should be applied more frequently to burn areas in which the cream might be removed through involuntary movement of the patient.
Treatment must be continued until satisfactory healing is achieved or until the burn site is ready for grafting. Do not miss any doses. If you miss a dose, apply it as soon as possible. However, if it is almost time for your next dose, skip the missed dose and go back to your regular dosing schedule. Do not use two doses at once.
Dressings are unnecessary but covering with fine mesh gauze and bandage will be more comfortable to most patients. It is recommended to apply hydrotherapy and mechanical debridement in patients with third-degree burns. Reapply immediately after hydrotherapy.
The drug should not be withdrawn from the therapeutic regimen as long as the possibility of infection exists, except when a significant adverse reaction occurs.
Premature and newborn infants up to 2 months of age
Use and dose must be determined by the physician.
Silver sulfadiazine (SILVEDERMA) is contraindicated in patients who are hypersensitive to sulfonamides or to any other component of the preparation.
Sulfonamide treatment is usually contraindicated in premature or newborn infants during the first 2 months of life because of the risk of producing kernicterus; for the same reason, they are generally contraindicated in women approaching term and in breast-feeding mothers.
It is advised not to use silver sulfadiazine (SILVEDERMA) cream in patients sensitive to sulfonamides and in pregnant women. However, due to the hazards of sepsis in severe burns, the use of silver sulfadiazine in such patients must be determined individually.
WARNINGS AND PRECAUTIONS
Silver sulfadiazine may be absorbed following topical application and produce systemic effects similar to those of other sulfonamides.
Transient leukopenia does not usually require withdrawal of silver sulfadiazine, but blood counts should be monitored to ensure they return to normal within a few days. Systemic absorption of silver, resulting in argyria, can occur when silver sulfadiazine is applied to large area wound or over prolonged periods.
Significant quantities of sulfadiazine can be absorbed following prolonged treatment of extensive burns. Monitoring of serum levels during prolonged treatment is not necessary except possibly, in patients with impaired renal or hepatic function.
It is difficult to eliminate free sulfadiazine that is absorbed through the wound in patients with impaired renal or hepatic function. An accumulation of the medicinal product may occur as the elimination decreases.
The application on open lesions should be avoided in these cases, especially in ulcers. Due caution is advised in order to avoid crustalluria, although this kind of toxicity is not demonstrated. Adequate fluid intake is necessary to reduce the risk of possible crystalluria.
Precaution is required in patients known to be sensitive to systemic sulfonamides and in individuals who are known to have glucose-6-phosphate dehydrogenase deficiency.
Sunlight may produce a grey coloring of silver sulfadizine. It is therefore recommended to avoid exposure of areas treated with silver sulfadiazine (SILVEDERMA) cream to direct sunlight.
Absorption of sulfadiazine by application of silver sulfadiazine (SILVEDERMA) cream:
Approximately 10 % of sulfadiazine contained in silver sulfadiazine is absorbed (5 g of silver sulfadiazine contains approximately 3 g of sulfadiazine).
In an extensive burn, 500 g of cream may be applied. In this case, 300 mg of sulfadiazine may be absorbed in 5 g of silver sulfadiazine. This is an insignificant amount to cause renal problems.
However, in patients with very extensive burns, the presence of sulfa crystals in urine should be monitored. Its volume should remain at 50 – 100 mL/hour with the corresponding administration of parenteral or oral liquid preparations (electrolyte solutions, etc.)
Silver sulfadiazine decreases autolysis of eschar because it attenuates or eliminates local antibacterial action. As such, hydrotherapy and debridement should be performed daily to enhance the rapid removal of eschar in patients with third-degree burns.
Pregnancy and lactation
A reproductive study was carried out in rabbits at doses three to ten times the concrentration of silver sulfadiazine in SILVEDERMA cream and no harm to the fetus due to the silver sulfadiazine content was detected. However, there are no adequate and well controlled studies in pregnant women.
Since reproductive studies in animals are not always predictive of human response, this drug should be used during pregnancy only if it is clearly justified, especially in pregnant women approaching or at term.
It is not known if silver sulfadiazine is excreted in human milk. However, sulfonamides are known to be excreted in human milk and that all sulfonamide derivatives increase the possibility of kernicterus.
Because of the possibility of serious adverse reactions from sulfonamides in nursing infants, a decision should be made to either discontinue nursing or to discontinue the treatment, taking into consideration the importance of the drug to the mother.
EFFECTS IN THE ABILITY TO DRIVE VEHICLES OR OPERATE MACHINERY
Silver sulfadiazine (SILVEDERMA) cream has no effects on the ability to drive vehicles or operate machinery.
The application of silver sulfadiazine (SILVEDERMA) cream is painless and usually has a good tolerance. Local pain and irritation are uncommon; the separation of the eschar may be delayed and fungal invasion of the wound may occur. However, a small percentage of patients experience rash, pruritus or a burning sensation.
Rarely, reversible leukopenia characterized by a decrease in the neutrophil count may occur. The maximum white blood cells depression occurs within 2 to 4 days of the commencement of therapy. Leukopenia rebounds to normal sometimes spontaneously and always upon discontinuation of treatment.
Silver sulfadiazine is not antagonized by p-aminobenzoic acid (PABA) or related compounds. The silver content of silver sulfadiazine may inactivate enzymatic debriding agents.
Cimetidine may increase the risk of leukopenia.
The monitoring of the plasma levels of sulfadiazine is not necessary, except probably in patients with impaired hepatic or renal functions when the drug is applied to an extensive surface under occlusive bandage or to damaged skin especially in burn areas.
Should a massive absorption of the drug occur, its elimination through the urine must be enhanced with the ingestion of abundant bicarbonate liquid preparations. In the event of serious crystalluria, urethral catheterization may be necessary.