Biguanide antiseptic and disinfectant active against a broad spectrum of bacteria, mycobacteria, viruses and fungi.
50 cases reported between 1967 and 1984:
22 with hypotension, 13 with dyspnea, 9 with anaphylactic shock, 4 with cyanosis.
Risk factors
For anaphylactic reactions: contact dermatitis to chlorhexidine.
Clinical manifestations
General: anaphylactic shock.
Respiratory: bronchospasm, occupational asthma.
Cutaneous: pruritus, erythema, urticaria, contact dermatitis, photosensitive dermatitis, fixed drug eruption.
Anaphylactic reactions have been reported after urinary catheterization, disinfection of a drain insertion site, topical application of a dressing on a burn, and placement of a central venous catheter.
Diagnostic methods
Cutaneous testing.
Skin-prick tests: 0.005% to 0.05%.
Intradermal skin-tests: 0.02 ml at 0.0002% to 0.002% concentrations.
Positive in anaphylaxis cases.
Patch-tests 1%: positive in contact dermatitis.
Specific IgE (RAST).
Histamine release test.
IgE-mediated hypersensitivity.
Avoidance in allergic patients.
Do not use chlorhexidine gluconate on mucosa.
Use at lowest bactericidal concentration (0.05%) on wound surfaces.


  1. Ebo D.G, Stevens W.J, Bridts C.H, Matthieu L, "Contact allergic dermatitis and life-threatening anaphylaxis to chlorhexidine", J. Allergy. Clin. Immunol, 1998; 101 (1.1): 128-9
  2. Oda T, Hamasaki J, Kanda N, Mikami K, "Anaphylactic shock induced by an antiseptic-coated central venous catheter", Anesthesiology., 1997; 87 (5): 1242-4
  3. Ramselaar C.G, Craenen A, Bijleveld R.T, " Severe allergic reaction to intraurethral preparation containing chlorhexidine", Br. J. Urol., 1992; 70 (4): 451-2
  4. Okano M, Nomura M, Hata S, Okada N, Sato K, Kitano Y, Tashiro M, Yoshimoto Y, Hama R, Aoki T, "Anaphylactic symptoms due to chlorhexidine gluconate", Arch. Dermatol., 1989; 125: 50-2.

As in all diagnostic testing, the diagnosis is made by the physican based on both test results and the patient history.