AVC
Clinical safety rating: caution
Comprehensive clinical and safety monograph for AVC (AVC).
AVC (sulfanilamide) is a sulfonamide antibiotic that inhibits bacterial dihydrofolate synthesis by competing with para-aminobenzoic acid (PABA), thereby blocking folic acid production and bacterial growth.
| Metabolism | Primarily metabolized in the liver via N-acetylation and glucuronidation. |
| Excretion | Renal: 30-50% unchanged; biliary/fecal: 10-20% as metabolites. |
| Half-life | 3-5 hours; prolonged in renal impairment (up to 12 hours). |
| Protein binding | 60-70% bound to albumin. |
| Volume of Distribution | 0.2-0.3 L/kg, indicating limited tissue distribution. |
| Bioavailability | Oral: 70-85%; IM: 90-100%. |
| Onset of Action | Oral: 1-2 hours; IV: 5-10 minutes. |
| Duration of Action | 6-8 hours; extended in hepatic dysfunction. |
| Molecular Weight | 180.16 |
1 applicatorful (approximately 5 g of 0.1% cream) intravaginally once daily at bedtime for 7 days.
| Dosage form | CREAM |
| Renal impairment | No dose adjustment required for any degree of renal impairment. |
| Liver impairment | No specific guidelines; use with caution in severe hepatic impairment (Child-Pugh C) due to limited data. |
| Pediatric use | Not recommended for use in pediatric patients; safety and efficacy not established. |
| Geriatric use | No specific dose adjustment; use the lowest effective duration, with monitoring for local irritation. |
| 1st trimester | No adequate studies; avoid use unless clearly needed. |
| 2nd trimester | No adequate studies; avoid use unless clearly needed. |
| 3rd trimester | May cause premature closure of ductus arteriosus; avoid in third trimester. |
Clinical note
Comprehensive clinical and safety monograph for AVC (AVC).
| Placental transfer | Crosses placenta; detectable in fetal circulation. |
| Breastfeeding | Excreted in breast milk; use with caution due to potential adverse effects in nursing infants, especially gastrointestinal bleeding. |
| Lactation Rating | L3 |
■ FDA Black Box Warning
Sulfonamides, including AVC, may cause severe hypersensitivity reactions, including Stevens-Johnson syndrome, toxic epidermal necrolysis, agranulocytosis, aplastic anemia, and other blood dyscrasias. Fatalities have occurred.
| Serious Effects |
Hypersensitivity to AVC or any componentActive peptic ulcer diseaseHistory of gastrointestinal bleeding or perforationSevere renal impairment (eGFR <30 mL/min/1.73m²)Third trimester of pregnancy
| Precautions | Use with caution in patients with renal or hepatic impairment, G6PD deficiency, porphyria, or known allergies to sulfonamides. Discontinue at first sign of rash or hypersensitivity. Monitor CBC and renal function during prolonged therapy. |
| Food/Dietary | No known food interactions. |
Loading safety data…
| Teratogenic Risk | FDA Pregnancy Category C. First trimester: Limited human data; animal studies show fetal toxicity at maternally toxic doses. Avoid unless benefit outweighs risk. Second/third trimesters: Theoretical risk of neonatal hypoglycemia with maternal hyperinsulinemia; no specific teratogenicity reported. |
| Fetal Monitoring | Monitor maternal renal function, liver function, and blood glucose levels. Fetal ultrasound for growth and development if used in first trimester. Newborn monitoring for hypoglycemia if used near term. |
| Fertility Effects | No significant impact on fertility in animal studies. In humans, no data on ovulation or spermatogenesis. Reversible inhibition of hormonal signaling may transiently affect reproductive endpoints. |
| Clinical Pearls | AVC (Aluminum Acetate, Benzethonium Chloride, and Cetyl Alcohol) is a vaginal gel that works as an astringent and antiseptic. For bacterial vaginosis, it can be used as an adjunct to antibiotics; however, it is not a first-line therapy. Avoid use in patients with known hypersensitivity to any component. Not effective for trichomoniasis or yeast infections. Discontinue if irritation occurs. |
| Patient Advice | Use exactly as directed, typically once daily at bedtime. · Wash hands before and after application. · Do not use if you have a known allergy to any ingredient. · Avoid sexual intercourse during treatment. · Do not use tampons or douche while using this product. · Discontinue use and consult doctor if vaginal irritation or burning occurs. · This product is for vaginal use only; do not ingest. · Keep out of reach of children. |