Monograph: |
Gentian Violet
The name methyl violetβCl Basic Violet I: Colour Index No.
42535βhas been used as a synonym for gentian violet, but is
applied to a mixture of the hydrochlorides of the higher
methylated pararosanilines consisting primarily of the tetra-
methyl-, pentamethyl-. and hexamethyl- compounds.
Dark green powder or greenish, glistening gentians with a me-
tallic lustre: odourless or almost odourless. Sparingly soluble
in water; soluble I in 10 of alcohol and I in 15 of glycerol;
also soluble in chloroform; practically insoluble in ether.
Incompatibilities. The antimicrobial activity of Gentian violet
may be diminished through incompatibilities (see below), de-
creasing pH, or through combination with organic matter.
The antibacterial activity of gentian violet was inhibited in
suspensions of bentonite with which it formed a stable com-
plex.'
Adverse Effects and Precautions
Topical application of gentian violet can produce irritation and
ulceration of mucous membranes. Ingestion of gentian violet
during prolonged or frequent treatment for oral candidiasis
has resulted in oesophagitis, laryngitis, and iracheitis; inges-
tion may also cause nausea, vomiting, diarrhoea, and abdom-
inal pain. In the UK it is recommended that gentian violet
should not be applied to mucous membranes or open wounds.
Contact with the eyes or broken skin should be avoided. Crys-
tal violet may stain skin and clothing.
Animal carcinogenicity has restricted its use.
Carcinogenicity. Gentian violet has been shown in vitro to
be capable of interacting with DNA of living cells,' and has
demonstrable carcinogenicity in mice}
Effects on the skin and mucous membrane Necrotic
skin reactions have been reported following the use of topical
I % aqueous solutions of gentian violet;' areas affected include
the submammary folds, gluteal fold, genitalia and toe-webs.
Similar reactions were observed in 2 patients following use of
1% gentian violet or brilliant green on stripped skin. Oral ul-
ceration developed in all of 6 neonates treated with aqueous
gentian violet 0.5 or 1% for oral candidiasis.2
In the UK it is recommended that gentian violet should not be
applied to mucous membranes or open wounds.
Effects on the urinary tract. Severe haemorrhagic cystitis
rapidly occurred in a 32-year-old woman after accidental in-
jection through the urethra of a solution of gentian violet 1%
and alcohol 2%. Severe cystitis was also reported following
instillation into the bladder of a solution containing gentian
violet and brilliant green 1:1 (Bonney's blue).
Porphyria. Gentian violet has been associated with clinical
exacerbations of porphyria and is considered unsafe in por-
phyric patients.
Uses and Administration
Gentian violet is a triphenylmethane antiseptic dye effective
against some Gram-positive bacteria, particularly Staphylo-
coccus spp., and some pathogenic fungi such as Candida spp.
It is much less active against Gram-negative bacteria and in-
effective against acid-fast bacteria and bacterial spores. Its ac
tivity increases as pH increases.
Gentian violet has been applied topically as a 0.25 to I.Ofb
aqueous solution or as a cream for the treatment of bacterial
and fungal infections, but in the UK its use is now restricted
to application to unbroken skin because of concern over ani-
mal carcinogenicity. However, it may be used as a 0.5% solu-
tion with brilliant green 0.5% (Bonney's blue) for skin
marking prior to surgery.
In the UK, gentian violet is no longer permitted for use in
foods.
Trypanosomlasis. Gentian violet is used in some countries
to prevent the transmission of American trypanosomiasis
by blood transfusion. In areas where the proportion
of blood donors seropositive for Trypanosoma cruzi is high,
emergency blood supplies positive for T. cruzi can be made
safe by the addition of gentian violet 125 mg per 500 mL of
blood and storing it for 24 hours at 40:2 it appears to work for
most but not all strains of T. cruzi in vitro.' There is no evi-
dence that gentian violet at such doses produces any side-ef-
fects apart from transient blue staining of the skin and
it has been suggested that addition of sodium ascor-
bate can markedly reduce the amount of gentian violet re-
quired.
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