Bactrim (Trimethoprim / Sulfamethoxazole)¶
Overview¶
| Field | Detail |
|---|---|
| Drug class | Sulfonamide antibiotic / Dihydrofolate reductase inhibitor |
| Formulation | Suspension (40/200 mg per 5 mL) or Tablets (80/400 mg) |
| Concentration | Suspension: Trimethoprim 8 mg / Sulfamethoxazole 40 mg per mL |
| Storage | Room temp |
Oral Graded Challenge (OGC)¶
Suspension Preparation
Use Bactrim Suspension (40 mg / 200 mg per 5 mL) which provides 8 mg / 40 mg per 1 mL.
Protocol¶
| Step | Dose (TMP/SMX) | Volume (Suspension) | Cumulative Dose |
|---|---|---|---|
| 1 | 16 mg / 80 mg | 2.0 mL | 16 mg / 80 mg |
| 2 | 64 mg / 320 mg | 8.0 mL | 80 mg / 400 mg |
| 3 | 80 mg / 400 mg | 10.0 mL | 160 mg / 800 mg |
Interval: 30–60 minutes between steps as per clinical orders.
Oral Ungraded Challenge¶
For patients with a low-risk history or as a final validation step.
Protocol¶
| Step | Dose (TMP/SMX) | Formulation | Cumulative Dose |
|---|---|---|---|
| 1 | 80 mg / 400 mg | 1 × Tablet | 80 mg / 400 mg |
Intravenous Skin Testing¶
Note: IV Bactrim skin testing is less common and protocols vary based on clinical need. Consult senior staff if IV testing is required.