Action and Spectrum

Drug Interaction

Adverse Reaction

Frequency defined 

>10% 

Headache (33%) 

Diarrhea (33%) 

Reversible oligospermia (33%) 

Gastric distress 

Photosensitivity 

Anorexia 

Nausea 

Vomiting  

1-10% 

Aplastic anemia 

Hypersensitivity 

Thyroid disturbance 

Thrombocytopenia 

Allergic reactions-rash 

Dizziness 

Itching 

Franulocytopenia 

Frequency not defined 

stevens Johnson syndrome 

Fever 

Hemolytic anemia 

Hepatitis 

Hematuria 

Intestinal nephritis 

Lyell’s syndrome 

Rash 

Granulocytopenia 

Leukopenia 

Jaundice 

Acute nephropathy 

Black Box Warning

Black Box Warning: 

sulfadiazine carries a black box warning for a rare but serious adverse reaction called Stevens-Johnson syndrome (SJS), which is a severe, life-threatening skin reaction that can progress to toxic epidermal necrolysis (TEN).

SJS/TEN can cause the skin to blister and peel and can also affect the mucous membranes, such as those in the eyes, mouth, and genitals. 

Contraindication / Caution

Contraindication/Caution: 

Contraindication: 

sulfadiazine is contraindicated in patients with a history of hypersensitivity to sulfonamides or any of the other ingredients in the medication. It should not be used in patients with severe hepatic or renal impairment, as the drug is gets metabolized by the liver and excreted by the kidneys. 

sulfadiazine should also not be used in patients with a history of blood disorders, such as anemia, thrombocytopenia, or leukopenia, as the medication can further exacerbate these conditions. Additionally, it should be used with caution in patients with a history of allergies, asthma, or G6PD deficiency. 

sulfadiazine is not recommended for use during pregnancy or lactation, as it may be harmful to the developing fetus or nursing infant. The medication should only be used under the guidance of a healthcare professional, and appropriate monitoring and supportive care should be provided as needed during treatment.  

Caution: 

sulfadiazine should be used under caution in patients with a history of liver or kidney disease, as the medication is primarily metabolized by the liver and excreted by the kidneys. Patients with impaired liver or kidney function may be at increased risk of toxicity or adverse effects. 

sulfadiazine should also be used with caution in patients with a history of allergies or asthma, as the medication can cause allergic reactions and exacerbate these conditions. Patients with G6PD deficiency should also be monitored closely for signs of hemolytic anemia, which can be a potential adverse reaction to sulfonamides. 

sulfadiazine may interact with other medications, including warfarin and methotrexate, and should be used with caution in patients taking these medications. It may also interfere with certain laboratory tests, including urine tests for glucose, causing false results.  

Comorbidities: 

sulfadiazine should be used under caution in patients with comorbidities, particularly those that affect the liver, kidneys, or blood. Patients with liver or kidney disease may be at increased risk of toxicity or adverse effects, as the medication is primarily metabolized by the liver and excreted by the kidneys. 

Patients with blood disorders, such as anemia, thrombocytopenia, or leukopenia, should also be monitored closely during treatment with sulfadiazine, as the medication can further exacerbate these conditions. 

Patients with allergies or asthma should be monitored for signs of allergic reactions, which can be a potential adverse effect of sulfadiazine. Patients with G6PD deficiency should also be monitored closely for signs of hemolytic anemia, which can be a potential adverse reaction to sulfonamides. 

Pregnancy / Lactation

Pregnancy consideration: pregnancy category C 

Lactation: sulfadiazine is excreted into human milk.  

Pregnancy category: 

• Category A: Satisfactory and well-controlled studies show no risk to the fetus in the first or later trimester. 
• Category B: There is no evidence of risk to the fetus found in animal reproduction studies and there are not enough studies on pregnant women. 
• Category C: Adverse effects on the fetus found with evidence in animal reproduction studies and no adequate evidence for an effect in humans, care must be taken for potential risks in pregnant women. 
• Category D: There is adequate data available with sufficient evidence of human fetal risk from various platforms, but despite potential risks may be used only in emergency cases for potential benefits. 
• Category X: Drugs listed in this category outweigh risks over benefits These category drugs should be prohibited for pregnant women. 
• Category N: There is no data available for the drug under this category. 

Pharmacology

Pharmacology: 

sulfadiazine is a sulfonamide antibiotic that works by inhibiting the growth and reproduction of bacteria. Sulfonamides work by interfering with the synthesis of folic acid, which is necessary for the growth and replication of bacteria. 

sulfadiazine acts as a competitive inhibitor of the enzyme dihydropteroate synthase, which is involved in the synthesis of folic acid. This inhibition prevents the production of folic acid and ultimately leads to the death of the bacteria. 

sulfadiazine is well-absorbed from the gastrointestinal tract and reaches therapeutic concentrations in the blood and tissues. The medication is metabolized primarily by the liver and excreted by the kidneys. 

sulfadiazine has a broad spectrum of activity against gram-positive and gram-negative bacteria, as some protozoa. It is commonly used to treat infections caused by Streptococcus pyogenes, Streptococcus pneumoniae, Staphylococcus aureus, Escherichia coli, and other bacteria.  

Pharmacodynamics: 

sulfadiazine has a bacteriostatic effect, meaning that it inhibits the growth and reproduction of bacteria rather than killing them outright. It acts by interfering with the synthesis of folic acid, which is an essential component of the bacterial cell wall. 

sulfadiazine acts as a competitive inhibitor of the enzyme dihydropteroate synthase, which is involved in the synthesis of folic acid. By inhibiting this enzyme, sulfadiazine prevents the production of folic acid and ultimately leads to the death of the bacteria. 

The activity of sulfadiazine is dependent on the concentration of the medication in the body. The minimum inhibitory concentration is the lowest concentration of the medication that is needed to inhibit the growth of bacteria. The MIC of sulfadiazine varies depending on the type of bacteria being treated. 

The effectiveness of sulfadiazine can also be affected by other factors, such as the site of infection, the patient’s immune system, and the presence of other medications. In some cases, combination therapy with other antibiotics may be necessary to achieve optimal treatment outcomes.  

Pharmacokinetics: 

Absorption 

sulfadiazine is well-absorbed from the gastrointestinal tract, with peak plasma concentrations achieved within 1-4 hours after oral administration. Food may not significantly affect the absorption of the medication. 

Distribution 

sulfadiazine is widely distributed throughout the body, with high concentrations achieved in the liver, kidneys, and lungs. The medication crosses the placenta and is excreted in breast milk. sulfadiazine is also distributed into the cerebrospinal fluid (CSF), although concentrations achieved in the CSF may be lower than those in the plasma. 

Metabolism 

sulfadiazine is primarily metabolized by the liver to its active form, sulfamethoxazole. The medication may also undergo acetylation in the liver to form acetylated metabolites. 

Elimination and excretion 

sulfadiazine and its metabolites are primarily excreted by the kidneys, with approximately 90% of the medication excreted unchanged in the urine. The medication has a half-life of approximately 7-15 hours in adults, although this may be prolonged in patients with renal impairment. 

Adminstartion

Administration: 

sulfadiazine is a type of antibiotic medication that is used to treat bacterial infections. It acts by inhibiting the growth of bacteria and preventing their reproduction. 

The administration of sulfadiazine typically involves taking the medication orally in the form of tablets or capsules. The duration and dosage of treatment depend on the severity of the infection and other factors such as the patient’s age and medical history. 

Patients should not exceed the recommended dosage or duration of treatment, as this can lead to antibiotic resistance and other complications. 

Patient Information Leaflet

Patient information leaflet 

Generic Name: sulfadiazine 

Pronounced: [ sull-fa-DYE-ah-zeen ]  

Why do we use sulfadiazine? 

sulfadiazine is used to treat a variety of bacterial infections, including: 

• Urinary tract infections 
• Respiratory tract infections 
• Skin and soft tissue infections 
• Meningitis 
• Toxoplasmosis (a parasitic infection) 
• Rheumatic fever 

sulfadiazine works by inhibiting the growth of bacteria and preventing their reproduction, allowing the body’s immune system to effectively fight off the infection. It is typically used in combination with other antibiotics, depending on the type and severity of the infection.