Visipaque (Iodixanol)¶
Overview¶
| Field | Detail |
|---|---|
| Drug class | Isotonic non-ionic dimeric iodine-based contrast medium |
| Stock formulation | 320 mg I/mL (Common) or 270 mg I/mL |
| Reconstituted conc. | N/A (Ready to use) |
| Storage | Room temp; Protect from light and X-rays |
Preparation¶
Before you start
Check the iodine concentration. Usually 320 mg I/mL. Ensure the solution is at room temperature and clear.
Equipment needed¶
- 1 × Visipaque 320 mg I/mL vial/bottle
- Normal saline (NS) — for IDT dilutions
- 1 mL syringes × 3 (for test doses/dilutions)
- 25 G needles
Step 1 — Prepare the SPT solution (320 mg I/mL — neat)¶
- Draw up 0.5–1 mL of the stock (320 mg I/mL) into a 1 mL syringe.
- Label: "Visipaque SPT 320 mg I/mL".
Step 2 — Prepare IDT dilutions¶
Prepare in this order, using a fresh syringe for each step.
-
IDT 1:10 (32 mg I/mL):
- Draw 0.1 mL of stock (320 mg I/mL) into a 1 mL syringe. Add 0.9 mL NS. Mix. (This is 32 mg I/mL — 1:10).
- Label: "Visipaque IDT 1:10".
-
IDT 1:100 (3.2 mg I/mL):
- Draw 0.1 mL of the 1:10 syringe into a new 1 mL syringe. Add 0.9 mL NS. Mix. (This is 3.2 mg I/mL — 1:100).
- Label: "Visipaque IDT 1:100".
Skin prick test (SPT)¶
| Reagent | Concentration |
|---|---|
| Test solution | Neat (320 mg I/mL) |
| Positive control | Histamine 10 mg/mL |
| Negative control | Normal saline |
Interpretation: Wheal ≥3 mm vs negative control = positive.
Intradermal test (IDT)¶
Dilution series¶
| Step | Dilution | Concentration | Preparation |
|---|---|---|---|
| 1 | 1:100 | 3.2 mg I/mL | 0.1 mL of 1:10 + 0.9 mL NS |
| 2 | 1:10 | 32 mg I/mL | 0.1 mL neat + 0.9 mL NS |
Inject: 0.05 mL intradermal. Read at 15–20 minutes. Delayed Reading: If history is suggestive of a delayed reaction, re-read at 24 and 48 hours.