PREDSULFAIR
Clinical safety rating: caution
Comprehensive clinical and safety monograph for PREDSULFAIR (PREDSULFAIR).
PREDSULFAIR is a combination of prednisolone (corticosteroid) and sulfacetamide (sulfonamide antibiotic). Prednisolone suppresses inflammation by inhibiting phospholipase A2, reducing prostaglandin and leukotriene synthesis. Sulfacetamide inhibits bacterial dihydropteroate synthase, blocking folate synthesis.
| Metabolism | Prednisolone is primarily metabolized in the liver via CYP3A4. Sulfacetamide is metabolized via acetylation and glucuronidation. |
| Excretion | PREDSULFAIR is a fixed-dose combination of prednisolone and sulfafurazole. Prednisolone is primarily metabolized hepatically; inactive metabolites are excreted renally (<30% unchanged). Sulfafurazole is acetylated and glucuronidated; parent drug and metabolites are excreted renally (≥90%, with 15-30% unchanged). Biliary/fecal elimination is minimal for both components (<5%). |
| Half-life | Prednisolone: 2.1–3.5 hours (plasma); biological half-life 12–36 hours (duration of HPA axis suppression). Sulfafurazole: 3–6 hours (normal renal function), prolonged to 12–24 hours in renal impairment. |
| Protein binding | Prednisolone: 70–90% bound to corticosteroid-binding globulin (CBG) and albumin; binding decreases at higher doses. Sulfafurazole: 40–60% bound to albumin; binding decreases in uremia. |
| Volume of Distribution | Prednisolone: Vd 0.5–1.0 L/kg, indicating extensive distribution into tissues. Sulfafurazole: Vd 0.2–0.4 L/kg, primarily confined to extracellular fluid. |
| Bioavailability | Oral: Prednisolone ~80–100% (immediate-release); sulfafurazole ~90–100%. Ophthalmic: corneal penetration ~2–10% for prednisolone; sulfafurazole limited to topical effect with minimal systemic absorption. |
| Onset of Action | Oral: Prednisolone anti-inflammatory effect within 2–4 hours; peak plasma levels at 1–2 hours. Ophthalmic: Onset within 30–60 minutes for ocular inflammation. Sulfafurazole bacteriostatic effect begins within 2–4 hours after oral administration. |
| Duration of Action | Prednisolone: Anti-inflammatory effect persists 12–36 hours after single oral dose; ophthalmic effect 4–6 hours. Sulfafurazole: Antimicrobial effect for 6–12 hours depending on dose and renal function. |
| Molecular Weight | 360.44 |
Prednisolone 0.5-1 mg/kg orally once daily, maximum 60 mg/day; Sulfasalazine 500 mg orally twice daily, increased by 500 mg weekly to maintenance 2-3 g/day in divided doses.
| Dosage form | OINTMENT |
| Renal impairment | eGFR >50 mL/min: no adjustment; eGFR 10-50 mL/min: reduce sulfasalazine dose by 50%; eGFR <10 mL/min: contraindicated (sulfasalazine). Prednisolone no adjustment. |
| Liver impairment | Child-Pugh A: caution with prednisolone; avoid sulfasalazine. Child-Pugh B: reduce prednisolone dose by 50%; avoid sulfasalazine. Child-Pugh C: contraindicated. |
| Pediatric use | Prednisolone: 1-2 mg/kg/day orally in divided doses, maximum 60 mg/day. Sulfasalazine: 30-50 mg/kg/day orally in 2-4 divided doses, maximum 2 g/day. |
| Geriatric use | Start at lowest effective dose; monitor for osteoporosis, hyperglycemia, and immunosuppression with prednisolone; sulfasalazine: increased risk of hematologic toxicity; monitor CBC and renal function regularly. |
| 1st trimester | Prednisolone is generally avoided in the first trimester due to a small increased risk of oral clefts. Use only if clearly needed. |
| 2nd trimester | May be used with caution; monitor for fetal growth restriction and maternal hyperglycemia. |
| 3rd trimester | May cause adrenal suppression in the newborn if used near term. Taper dose before delivery. |
Clinical note
Comprehensive clinical and safety monograph for PREDSULFAIR (PREDSULFAIR).
| Placental transfer | Prednisolone crosses the placenta; about 10-20% of maternal concentration reaches fetus. Higher transfer with prednisone than prednisolone. |
| Breastfeeding | Prednisolone is excreted into breast milk in low concentrations. No adverse effects reported at maternal doses up to 40 mg/day. Monitor infant for adrenal suppression if high doses are used. |
■ FDA Black Box Warning
Sulfonamides are associated with severe adverse reactions including Stevens-Johnson syndrome, toxic epidermal necrolysis, fulminant hepatic necrosis, agranulocytosis, aplastic anemia, and other blood dyscrasias. Prolonged use of corticosteroids may result in elevated intraocular pressure, glaucoma, cataracts, and secondary ocular infections.
| Serious Effects |
Systemic fungal infectionsHypersensitivity to prednisolone or any componentAdministration of live or live attenuated vaccines
| Precautions | Prolonged use may lead to increased intraocular pressure, glaucoma, cataract formation, delayed wound healing, and secondary infections. Sulfonamide components may cause hypersensitivity reactions including Stevens-Johnson syndrome. Use with caution in patients with glaucoma, corneal thinning, or known sulfonamide allergy. Bacterial resistance may develop with prolonged use. |
| Food/Dietary | No known food interactions. However, alcohol may increase risk of gastrointestinal side effects if systemic absorption occurs (unlikely with ophthalmic use). |
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| Lactation Rating |
| L2 (Safer) |
| Teratogenic Risk | Prednisolone crosses the placenta but is largely inactivated by placental 11β-HSD2. First trimester exposure (≤15 mg/day) is not associated with major malformations; risk of cleft palate increases with doses >15 mg/day (absolute risk ~1-2%). Second/third trimester: possible intrauterine growth restriction, preterm birth, adrenal suppression in neonate. High doses (>30 mg/day) increase risk of premature rupture of membranes. |
| Fetal Monitoring | Monitor maternal blood pressure, blood glucose, weight gain, signs of infection. Fetal ultrasound for growth and amniotic fluid volume. Neonatal assessment for adrenal insufficiency (e.g., cortisol levels) if mother received >15 mg/day in late pregnancy. |
| Fertility Effects | No direct impairment of fertility. Chronic high doses may cause menstrual irregularities or suppress HPA axis, potentially affecting ovulation; reversible upon dose reduction. |
| Clinical Pearls | PREDSULFAIR (prednisolone ophthalmic suspension 1% with sulfacetamide 10%) is a fixed combination corticosteroid-antibiotic. Use only when both steroid and sulfonamide are needed; avoid for viral, fungal, or tubercular ocular infections. Monitor intraocular pressure if used >2 weeks. Re-evaluate if no improvement in 48 hours. Shake vigorously before each use. Risk of corneal thinning with prolonged use. |
| Patient Advice | Shake the bottle well before each use. · Instill the prescribed number of drops into the affected eye(s). · Avoid touching the dropper tip to your eye or any surface. · Do not use while wearing contact lenses; wait at least 15 minutes after instillation before inserting lenses. · Report any eye pain, redness, or vision changes immediately. · Complete the full course as prescribed, even if symptoms improve. · Inform your doctor if you are pregnant, planning to become pregnant, or breastfeeding. · Tell your doctor about all medications you are taking, including over-the-counter drugs. · Do not use this medication longer than prescribed due to risk of eye complications. |