Patent Blue V


💊 Chemical information

Acid Blue 3; Azul Patente V; CI Food Blue 5; Colour Index No.
42051; E131. Calcium iniocyclohexa-2,5-dienylidene)-5-hydroxytoluene-2,4-disulphonate.
Chemical formula: (C27H31N2O7S2)2Ca = 1159.4.
CAS — 3536-49-0.


In Fr.

💊 Adverse Effects and Precautions

Hypersensitivity reactions may occur immediately or a few minutes after injection of patent blue V; on rare occasions they may be severe and include shock, dyspnoea, laryngeal spasm, and oedema. Nausea, hypotension, and tremor have been reported. Giving a small dose to test for hypersensitivity has been suggested.


An urticarial rash occurred in a 5-year-old girl after use of tablets containing patent blue V to disclose the presence of dental plaque.1 Severe anaphylactic reactions, including shock, have been reported.2-5
1. Chadwick BL, et al. Allergic reaction to the food dye patent blue. Br Dent J 1990; 168: 386–7
2. Woltsche-Kahr I, et al. Anaphylactic shock following peritumoral injection of patent blue in sentinel lymph node biopsy procedure. Eur J Surg Oncol 2000; 26: 313–14
3. Adverse Drug Reactions Advisory Committee (ADRAC). Patent blue V and anaphylaxis. Aust Adverse Drug React Bull 2002; 21: 10. Also available at: aadrb/aadr0208.htm (accessed 02/07/04
4. Wöhrl S, et al. Near-fatal anaphylaxis to patent blue V. Br J Dermatol 2004; 150: 1037–8
5. Dewachter P, et al. Anaphylactic reaction to patent blue V after sentinel lymph node biopsy. Acta Anaesthesiol Scand 2006; 50: 245–7.

💊 Uses and Administration

Patent blue V is injected subcutaneously to colour the lymph vessels so that they can be injected with a contrast medium. A dose of 0.25 mL of the 2.5% solution diluted with an equal volume of sodium chloride 0.9% or lidocaine hydrochloride 1% injected subcutaneously in each interdigital web space has been used. Additional injections at different sites may be required when the lower limbs are to be examined. A bluish skin colour may develop after injection but usually disappears after 24 to 48 hours. Patent blue V is used as a food colour.

Malignant neoplasms of the breast.

Intradermal injection of patent blue V at the site of a primary breast tumour has been used to identify the associated lymph nodes,1 but concern has been expressed regarding possible long-term staining of the skin.2
1. Borgstein PJ, et al. Intradermal blue dye to identify sentinel lymph-node in breast cancer. Lancet 1997; 349: 1668–9
2. Giuliano AE. Intradermal blue dye to identify sentinel lymph node in breast cancer. Lancet 1997; 350: 958.
Published May 08, 2019.