How gentian violet works

NOTE: Gentian violet has been removed from our treatment suite due to an international health warning, despite the liquid being available over the counter and online in the USA.

Please read the warning and use gentian violet safely at your own risk.

Gentian violet has antibacterial, antifungal and antiparasitic properties, and is a solid – though messy – treatment for some vaginal infections, including yeast infections and other mixed flora infections.

Gentian violet is easy to use, has minimal side-effects, and is effective, but there are limitations. The way the dye works is only effective against a set of microbes, while not affecting or only somewhat affecting others.

Gentian violet is also known as crystal violet, methyl violet, and it’s real name, hexamethyl pararosaniline.

Gentian violet has been used for a long time as an antiseptic in medicine, and was originally developed by a French chemist. Hans Gram devised the Gram stain to help figure out what classifications bacteria should go into, with the Gram stain still used today. Gentian violet as an antimicrobial went out of vogue with the development of antibiotics.

In 1891, gentian violet started being used as an antiseptic, but there were a lot of claims of ‘curing’ going on, and so it became challenging to separate fact from fiction.

Despite the scientific controversy, gentian violet was being used via injection to cure blood infections and successfully treating some cancers.

In the past, gentian violet has successfully cured:

• Staphylococcal meningitis
• Sepsis (blood infections)
• Trench mouth (ulcerative gingivitis, severe gum infection)
• Yeast infections
• Impetigo (staphylococcus or streptococcus)
• Burns
• Pinworm
• Fungal infections
• Sarcomas/melanoma
• MRSA in ear infections, graft infections, and others

Gentian violet is:

• Inexpensive
• Simple to prepare
• Chemically stable
• Active in low concentrations
• Broad spectrum antimicrobial action
• Minimal toxicity risk
• Not a cause of resistance in microbes
• Very messy!

Gentian violet is active against the following microbes:

• Very effective against yeasts
• Highly effective against gram-positive bacteria
• Very effective against Staphylococcus species
• Very effective against Streptococcus species
• Moderately effective against gram-negative bacteria
• Moderately effective against Mycobacterium

Specifically… (but not limited to)

• Atopobium vaginae (anaerobic gram-positive)
• Candida spp. (yeast)
• Candida albicans (yeast)
• Candida glabrata (yeast)
• Candida krusei (yeast)
• Enterococcus faecalis (aerobic gram-positive)
• Gardnerella vaginalis (anaerobic gram-positive)
• Lactobacillus spp. (aerobic gram-positive)
• Listeria monocytogenes (anaerobic gram-positive)
• Peptostreptococcus (anaerobic gram-positive)
• Staphylococcus aureus (aerobic gram-positive)
• Streptococcus agalactiae (Group B Streptococci, aerobic gram-positive)
• Streptococcus pyogenes (Group A Streptococci, aerobic gram-positive)

How gentian violet works

We’re not sure exactly how gentian violet works, but there are theories:

1. Alteration of redox potential
2. Inhibition of reduced nicotinamide adenine dinucleotides phosphate (NADPH) oxidases
3. Free radical formation
4. Formation of an un-ionised complex of bacteria with the dye
5. Inhibition of protein synthesis
6. Inhibition of glutamine synthesis
7. Uncoupling of oxidative phosphorylation
8. Inhibition of formation for the bacterial cell wall

Research into gentian violet and bacteria

Gentian violet has been used successfully in several fields, but a lot in dermatology. There are some limited case reports and small studies into using gentian violet for eczema that was colonised with Staphylococcus aureus, proving a useful treatment in difficult cases.

Gentian violet has been used for a long time to sterilise the umbilical stump after a baby is born. Methicillin-resistant Staph (MRSA) is successfully treated with gentian violet. In some areas, blood transfusions routinely contain gentian violet.

Can gentian violet treat gram-negative bacteria?

Even though gentian violet is less effective against gram-negative organisms (like those found in aerobic vaginitis), it is still effective, but it just takes longer.

Gentian violet inhibits the growth of Pseudomonas, a very virulent gram-negative bacteria, with interruptions to the bacterial biofilms too. This makes it very useful as a treatment and biofilm preventative tool.

Gentian violet action on fungi (yeasts)

Examples of systemic fungal infections being successfully eradicated with gentian violet injections exist. Candida is commonly treated with gentian violet, in particular amongst breastfeeding mothers on nipples and in babies mouths for oral thrush.

Gentian violet may be an alternative to drug antifungals, especially in cases of antifungal resistance, which is increasing with over-the-counter vaginal yeast treatment kits, misdiagnosis, and frequent recurrences. Gentian violet is known to inhibit yeast biofilms.

Gentian violet action on parasites, viruses, tumours, blood vessel conditions

Pinworm, for example, is often treated with gentian violet, and two studies have shown gentian violet also has antiviral activity.

Gentian violet also has anti-tumour actions, and can help treat angiogenesis, which is the development of new blood vessels near the surface of the skin (dermatological problems). 

Gentian violet has been used to treat post-radiation dermatitis.

Safety and toxicity of gentian violet

Gentian violet can interact with DNA in cells, with discussions going on regarding its cancer potential, despite its known anti-inflammatory and anti-tumour actions.

Mouse studies that involved feeding mice extremely large doses of gentian violet found an increase in liver cell cancers. Another study that had rats fed gentian violet had an increase in thyroid cancer after two years, likely due to gentian violet’s inhibition of thyroid peroxidase, causing hypothyroidism and the replication of thyroid cells.

Humans do not eat gentian violet (except in some cases via the food chain – animals may also be treated with it), and even treating thrush in a baby’s mouth would not result in enough gentian violet over any period of time to cause any type of cancer or thyroid condition.

Gentian violet is considered low risk and comes without contraindications for use besides the warning, which you should have read by now! No case of cancer has ever been linked to gentian violet in humans, and toxicity is limited to a few cases out of hundreds of millions of applications.

The United States Food and Drug Administration (FDA) allows the sale of gentian violet over the counter. This product is inexpensive and effective and can be considered where appropriate.

References

• Maley AM, Arbiser JL. Gentian Violet: A 19^th Century Drug Re-Emerges in the 21^st Century. Experimental dermatology. 2013;22(12):775-780. doi:10.1111/exd.12257.
• Adams, E., 1967, The antibacterial action of crystal violet, DOI: 10.1111/j.2042-7158.1967.tb09550.x
• PubChem entry on gentian violet