Chlorquinaldol

Introduction

Chlorquinaldol is monohydroxyquinoline, or quinolin-8-ol that is substituted by a methyl group at position 2 and chlorine at positions 5 and 7. It is a solid insoluble in water and the chemical name of chlorquinaldol is 5,7-dichloro-2-methyl-8-hydroxyquinoline. Chlorquinaldol is an antimicrobial agent used in the treatment of bacterial vaginosis. The structure is shown in fig. 1.

Fig. 1 Structure of chlorquinaldol

Application in the treatment of bacterial vaginosis

• Introduction of bacterial vaginosis

Bacterial vaginosis, commonly known as Gardnerella vaginitis, is a common dysbiosis that affects about 21 million women in the United States[1]. Patients generally range in age from 15 to 45 years old. The most common symptom of bacterial vaginosis is increased vaginal discharge that is usually white or gray and smells like fish. In addition, burning or itching in the vagina, or burning when urinating, may also occur in bacterial vaginosis. People with bacterial vaginosis are twice as likely to get a sexually transmitted infection, such as human immunodeficiency virus (HIV). Bacterial vaginosis also increases the early delivery risk among pregnant women. In general, douching, new or multiple sexual partners, antibiotics, smoking, and using an intrauterine device may cause bacterial vaginosis. In addition, the occurrence of bacterial vaginosis is related to the race and region. It is most common in parts of Africa and least common in Asia and Europe.

• Mechanism of action

Chlorquinaldol was approved by the European Medicines Agency as a combination tablet with promestriene for the treatment of bacterial vaginosis. Chlorquinaldol and promestriene are a combination of broad-spectrum bacteriostatic agents and vaginal mucosal protectors. Among them, chlorquinaldol can inhibit pathogen metabolism by changing the pH value of pathogen cells, eventually leading to the death of pathogens. In addition, human epithelial cells have no phagocytic function to chloroquinadol, so chlorquinaldol is safer in the treatment of bacterial vaginosis.

Other applications

Chlorquinaldol has inhibitory effect on not only fungal and bacterial, including Mycobacterium tuberculosis, but also viral and parasitic. Therefore, chlorquinaldol has been administered topically for the treatment of skin infections, dermatitis and allergic skin reactions for a long time, alone or in combination with diflucortolone valerate[2].

References

1. Bagnall, P., et al. Bacterial vaginosis: a practical review. Journal of the American Academy of Physician Assistants. 2017, 30(12): 15-21.

2. Bidossi, A., et al. Chlorquinaldol, a topical agent for skin and wound infections: anti-biofilm activity and biofilm-related antimicrobial cross-resistance. Infection and Drug Resistance. 2019(12): 2177-2189.