Silver sulfadiazine is a compound of sulfadiazine and silver nitrate. It has the astringent effect of silver and the antibacterial and anti-inflammatory effect of sulfadiazine. It is mainly used as an external medicine for the treatment of burn wounds. It is clinically effective in controlling, preventing, and killing Pseudomonas aeruginosa, as well as promoting wound healing, skin grafting, and regeneration.
In addition to the infection of burn wounds, it can also be used for the treatment of bedsore wounds, local frostbite, MRSA-infected ulcers and chronic cheilitis. The current production method of sulfadiazine silver salt is to react sulfadiazine powder with silver nitrate to produce sulfadiazine silver salt. In production, in order to increase the utilization rate of the more expensive silver nitrate, it is usually necessary to increase the amount of sulfadiazine by about 10%. After the reaction, the excess sulfadiazine cannot be recycled, so the cost of waste disposal is relatively high.
Sulfadiazine is a sulfonamide commonly used clinically in China at present. It is also called sulfadiazine and diazepam. The molecular structure of sulfadiazine is similar to p-aminobenzoic acid (PABA). It can compete with PABA in bacteria, which prevents PABA as a raw material to synthesize folic acid required by bacteria, and reduces the amount of metabolically active tetrahydrofolate, which is an essential substance used by bacteria to synthesize purines, thymines and deoxyribonucleic acid (DNA). Then, therefore it inhibits the growth and reproduction of bacteria.
Sulfadiazine has inhibitive effects for Streptococcus hemolyticus, Staphylococcus, Meningococcus, Pneumococcus, Neisseria gonorrhoeae, Escherichia coli, Shigella and other sensitive bacteria, as well as Chlamydia trachomatis, Actinomyces, Plasmodium, Nocardia stellate, Toxoplasma and other organisms.
The advantages of sulfadiazine are high effective concentration in the blood, low serum protein binding rate and easy penetration into the cerebrospinal fluid. It is the first choice for the treatment of epidemic meningitis. However, in recent years, meningococci are resistant to sulfadiazine and other sulfonamides. The drug-resistant strains have increased (20% reported domestically and 33% reported resistance to this product abroad).
Those who are resistant to this product can be treated with penicillins. The disadvantage of sulfadiazine is that it is easier to precipitate crystals in the urinary tract, so it is necessary to take sodium bicarbonate together. Studies in recent years have shown that its half-life is 17 hours, so it can be taken as an intermediate-effect sulfa drug, and it can be administered twice a day. But generally it is still used for short-term use. Sulfadiazine is commonly used clinically to treat epidemic cerebrospinal meningitis, upper respiratory tract infection, epidemic meningitis, otitis media, carbuncle, puerperal fever, plague, local soft tissue or systemic infection, urinary tract infection and acute bacillary dysentery. It can still be used in the respiratory tract Infection, intestinal infection, typhoid fever, etc.
This product is a medium-acting sulfonamide for the treatment of systemic infections. It has a broad antibacterial spectrum. It has an inhibitory effect on most Gram-positive and negative bacteria. It can inhibit meningococcus, streptococcus pneumonia, gonococcus, and hemolytic streptococcus. It has a strong effect and can penetrate into the cerebrospinal fluid through the blood-brain barrier.
Clinically, it is mainly used for meningitis, and it is the first choice for the treatment of meningitis. It can also treat other infections caused by the aforementioned sensitive bacteria. It is also often made into water-soluble sodium salt for injection.
Silver nitrate is a colorless crystal with a chemical formula of AgNO3, which is easily soluble in water. Pure silver nitrate is stable to light, but because the purity of general products is not enough, its aqueous solution and solids are often stored in brown reagent bottles. It is used in photographic emulsions, silver plating, mirror making, printing, medicine, hair dyeing, inspection of chloride, bromide and iodide, etc. It is also used in the electronics industry.
In analytical chemistry, it is used to precipitate chloride ions, and silver nitrate in working standard is used to calibrate sodium chloride solutions. In the inorganic industry, it is used to make other silver salts. In the electronics industry, it is used in the manufacture of conductive adhesives, new gas purifiers, A8x molecular sieves, silver-plated uniform pressure clothing and gloves for live working. In the photosensitive industry, it is used to manufacture photosensitive materials such as motion picture film, X-ray photographic film and photographic film. In the electroplating industry, it is used for silver plating of electronic components and other handicrafts. It is also widely used as a silver plating material for mirrors and vacuum flasks. In the battery industry, it is used to produce silver-zinc batteries. Used as a bactericide and corrosive in medicine. The daily chemical industry is used for dyeing hair and so on.
Silver nitrate is a strong oxidizer, corrosive product, and environmental pollutant. It can burn or explode when mixed with some organic matter or sulfur and phosphorus, and silver nitrate is corrosive. Once the skin is stained with silver nitrate solution, black spots will appear, which is due to the formation of black protein silver. Silver nitrate is toxic, and the lethal dose is about 10 grams.
When this product comes into contact with wound exudate, it is slowly metabolized, and part of the drug can be absorbed locally into the blood. Generally, the absorption is less than 1/10 of the dose, and the blood concentration of sulfadiazine can reach 10-20μg/ml. When the wound is wide and the amount of medicine used is large, the absorbed amount will increase and the blood concentration will be higher. Under normal circumstances, the absorption of silver in this product does not exceed 1% of its content. This product has poor penetration to necrotic tissue.
Silver sulfadiazine cream is indicated for the prevention and treatment of secondary wound infections in mild burns and scalds. Each gram contains 10 mg of silver sulfadiazine as the main ingredient, and white petrolatum, liquid paraffin, and glycerin as auxiliary materials. It is used to prevent and treat wound infections of mild burns and scalds. For topical application, apply directly to the wound surface or make the cream into an oil emery cloth for application, once a day.
Silver sulfadiazine was applied to the wounds of 162 burn patients (the burn depths were between superficial second degree and third degree), 96 cases of superficial second degree burn patients (the wounds healed after dressing change); 66 cases after the shock period (after surgical resection, the wounds healed after cutting the scabs and planting microscopic skin). 162 burn patients treated with silver sulfadiazine were followed up for 3 months to 2 years. And the wounds healed smoothly, the early infection rate was low, and deep second-degree wounds could heal under the scab. The silver sulfadiazine cream was used to treat 80 patients with burns (60 cases of superficial second-degree burns and 20 cases of deep second-degree burns).
The results showed that sulfadiazine silver salt cream used to treat shallow and deep burns achieved satisfactory Efficacy. The sulfadiazine silver salt was made into gel to treat 968 cases of burn wounds, and the effect was satisfactory.
The sulfadiazine silver salt was used to treat 15 cases of bedsore wounds with good curative effect. The reason is that bedsore wounds are susceptible to Pseudomonas aeruginosa and Escherichia coli. Silver sulfadiazine has a broad-spectrum bactericidal effect, and the scab can form a protective wound layer after application. In the curative effect standard, healing means that the local tissue is dry and crusted within 1 week of the pressure ulcer of stage Ⅱ~Ⅲ; the wound surface of the pressure ulcer of stage Ⅲ is dry and the new granulation tissue is flush with the surrounding skin on the 15th day.
Remarkable effect refers to reduced purulent secretion in 3 days and redness and swelling, and the area of the pressure ulcer gradually shrinks and becomes shallower within one week, and there is new granulation tissue hyperplasia around it; ineffective means that there are still a lot of local secretions after one week of treatment, the redness and swelling have not been alleviated, and there is no growth of new granulation tissue.
The silver sulfadiazine cream is used for the treatment of limb frostbite, and the results show that the effect is significant. Frostbite is a direct effect of low temperature on cells, ice crystal formation, cell membrane damage, increased permeability, cell dehydration, protein degeneration, and metabolic disorders. Low temperature causes tissue frostbite, tissue thawing, edema, hypoxia, low temperature directly affecting blood vessels, vascular endothelial shedding, increased vascular permeability, platelet aggregation, blood flow stasis, thrombosis, circulatory disorders, and thus causes tissue necrosis. Therefore, the treatment is mainly based on comprehensive treatment to protect the limbs, prevent infection, promote blood circulation, and prevent thrombosis.
Wound treatment should be treated with silver sulfadiazine. The silver sulfadiazine salt contains silver ions that can penetrate into the skin and play an antibacterial effect. At the same time, it can keep the wound surface dry and promote the healing of the scabs, and the clinical application effect is satisfactory.
Applying sulfadiazine silver salt cream to treat ulcers with MRSA infection, the results show that the effective rate is 72.7%, and there are no local and systemic side effects, so silver sulfadiazine cream can be used for the treatment of ulcers with MRSA infection.
Overall, silver sulfadiazine is convenient and easy to use, and has a good therapeutic effect on some mild to moderate burns, but we also need to pay attention to some of its adverse reactions during use.