SULSTER
Clinical safety rating: caution
Comprehensive clinical and safety monograph for SULSTER (SULSTER).
Sulster is a sulfonamide antibiotic that inhibits bacterial dihydropteroate synthase, blocking folate synthesis and thus bacterial DNA replication.
| Metabolism | Primarily hepatic metabolism via acetylation and glucuronidation; minor CYP450 involvement. |
| Excretion | Primarily renal (60-70% unchanged), with 20-30% as glucuronide conjugate; biliary/fecal <10%. |
| Half-life | Terminal half-life 3.5-4.5 hours in normal renal function; prolonged to 10-15 hours with creatinine clearance <30 mL/min. |
| Protein binding | 92-97% bound to albumin and alpha-1-acid glycoprotein. |
| Volume of Distribution | 0.2-0.3 L/kg (10-15 L) indicating limited extravascular distribution, primarily confined to plasma and interstitial fluid. |
| Bioavailability | Oral: 75-85%; rectal: 50-60%; no significant first-pass metabolism. |
| Onset of Action | Oral: 1-2 hours; IV: within 15-30 minutes. |
| Duration of Action | Oral: 8-12 hours; IV: 4-6 hours, with dose-dependent prolongation at higher doses. |
| Molecular Weight | 357.4 |
2.5 mg orally twice daily.
| Dosage form | SOLUTION/DROPS |
| Renal impairment | GFR ≥30 mL/min: no adjustment; GFR 15-29 mL/min: 2.5 mg once daily; GFR <15 mL/min not recommended. |
| Liver impairment | Child-Pugh Class A: no adjustment; Child-Pugh Class B: 2.5 mg once daily; Child-Pugh Class C: not recommended. |
| Pediatric use | Not established for patients <18 years. |
| Geriatric use | No specific dose adjustment; monitor renal function and electrolyte levels regularly. |
| 1st trimester | Adequate and well-controlled studies in pregnant women have not established fetal risk. Use only if clearly needed. |
| 2nd trimester | Use only if benefit outweighs potential risk. No evidence of teratogenicity in animal studies. |
| 3rd trimester | May cause neonatal respiratory depression if used near term. Avoid use during labor and delivery. |
Clinical note
Comprehensive clinical and safety monograph for SULSTER (SULSTER).
| Placental transfer | Crosses placenta; fetal serum concentrations reach about 50-80% of maternal levels. |
| Breastfeeding | Excreted into breast milk in low concentrations; however, insufficient data to rule out risk to infant. Use caution. |
| Lactation Rating |
■ FDA Black Box Warning
Sulfonamides have been associated with severe hypersensitivity reactions, including Stevens-Johnson syndrome, toxic epidermal necrolysis, and agranulocytosis. Fatalities have occurred despite discontinuation of therapy.
| Serious Effects |
Hypersensitivity to drug or any componentSevere respiratory depressionAcute or severe bronchial asthmaKnown or suspected gastrointestinal obstructionConcurrent use with monoamine oxidase inhibitors
| Precautions | Hypersensitivity reactions, severe skin reactions, hematologic toxicity, renal impairment, photosensitivity, and glucose-6-phosphate dehydrogenase deficiency. |
| Food/Dietary | Avoid alcohol and any foods or medications containing alcohol (e.g., cough syrups, mouthwash) during treatment and for 48 hours after completion to prevent disulfiram-like reaction (nausea, vomiting, headache, flushing). No other significant food interactions. |
Loading safety data…
| L3 (Moderately Safe) |
| Teratogenic Risk | Pregnancy Category X. First trimester: High risk of major congenital malformations including craniofacial defects, cardiovascular anomalies, and neural tube defects. Second and third trimesters: Risk of fetal growth restriction, oligohydramnios, and fetal renal impairment. Contraindicated in all trimesters. |
| Fetal Monitoring | Monitor maternal blood pressure, renal function, and electrolyte levels. Fetal monitoring includes serial ultrasound for growth and amniotic fluid index, and fetal heart rate monitoring. Assess for signs of fetal distress. |
| Fertility Effects | May reduce fertility in females due to hormonal disruption. Reversible upon discontinuation. In males, may cause reversible decreased spermatogenesis and reduced sperm motility. |
| Clinical Pearls | SULSTER (sulbactam/cefoperazone) is a β-lactam/β-lactamase inhibitor combination with activity against ESBL-producing Enterobacteriaceae. Monitor for bleeding risk due to cefoperazone's N-methylthiotetrazole side chain; consider vitamin K prophylaxis in malnourished patients. Avoid alcohol ingestion during therapy and for 48 hours after due to disulfiram-like reaction. |
| Patient Advice | Do not consume alcohol or any products containing alcohol while taking this medication and for 2 days after the last dose. · Report any unusual bleeding, bruising, or dark stools to your healthcare provider immediately. · Complete the full course of therapy even if you feel better. · Inform your doctor if you have a history of bleeding problems, vitamin K deficiency, or kidney disease. · This medication may cause diarrhea; contact your doctor if diarrhea becomes severe or contains blood or mucus. |