Gentian violet is an antiseptic dye that has been in use since 1890. The name is due to its colour – it is not made from gentian or violet flowers.
Gentian violet has antifungal and some antibacterial activity and has traditionally been used as a topical treatment for a variety of dermatological conditions. However, there is little clinical trial evidence to support its effectiveness or long-term safety, so for many diseases more modern treatments, such as antibiotics and other systemic medications, are favoured. In many countries gentian violet is no longer available for medical purposes.
Uses of gentian violet
Gentian violet has been used to treat the following dermatological conditions:
- Fungal infections, including fungal skin infections, oral candidiasis (oral thrush), and vulvovaginal candidiasis (vaginal thrush). More recently, gentian violet has been used to treat oral thrush in patients who are HIV-positive.
- Superficial bacterial skin infections such as infected eczema, boils, and chronic (long-standing) leg ulcers. Gentian violet may also be active against Methicillin-resistant Staphylococcus aureus (MRSA).
- Oral hairy leukoplakia (white plaques on the edges of the tongue). This condition occurs in patients with weakened immune systems, particularly HIV-positive individuals. Oral hairy leukoplakia is associated with Epstein-Barr virus (EBV), the cause of glandular fever. EBV infection results in the generation of reactive oxygen species; gentian violet is thought to work by inhibiting reactive oxygen species.
Gentian violet has also been used for other medical and industrial purposes.
|Other medical uses||Industrial uses|
|To prevent infection in the umbilical cord stump in newborns||Dyes for wood, silk, food, and cosmetics|
|To control some intestinal parasitic worms, e.g. threadworm||Ink for ballpoint pens|
|In blood banks to prevent blood transmission of Chagas disease|
|As a dye to stain structures in the eye, e.g. during eye surgery|
|In laboratories as the basis of the Gram stain (a common stain used to detect the presence of Gram-positive bacteria)|
Side effects of gentian violet
- Gentian violet can irritate mucous membranes (e.g. the tissues lining the eyes, gastrointestinal tract, and genital tract) if used at high concentrations. For example, if taken orally it can cause nausea, vomiting, diarrhoea, and abdominal pain
- There have been reports of gentian violet causing oral ulcers, even when used as a topical treatment at low concentrations
- It can cause necrotic skin reactions (blackened skin due to death of tissue), particularly when used at high concentrations around the skin folds (e.g. underneath the breast, around the genitals, and the toe webs)
- It can reduce the white blood cell count when administered intravenously (directly into a vein)
- It can stain skin and clothes; when applied to ulcers, staining may be permanent
- Laboratory studies have shown that gentian violet is capable of causing cancer in mice, but there is little evidence of this occurring in humans
Serious side effects are rare when gentian violet is used as a topical external treatment. Some authorities advise against applying gentian violet to mucous membranes and open wounds.