Ivermectin for treating papulopustular rosacea?

Ivermectin, a new topical treatment for the management of papulopustular lesions of rosacea.

Difficult to endure due to its stigmatising nature, papulopustular rosacea is a dermatosis characterised by a widespread redness of the face, accompanied by a visible dilation of blood vessels and the presence of papules and pustules. The usual treatment for this form of rosacea involves the use of metronidazole, an antibiotic that many people struggle to tolerate. In response, healthcare professionals have in recent years included ivermectin in the solutions for papulopustular rosacea. Discover more information about this medication here.

Published on October 7, 2024, by Marie, Scientific Editor — 5 min of reading

Ivermectin: What is its relevance in the case of papulopustular rosacea?

Ivermectin is a substance derived from avermectin, a macrocyclic organic compound with insecticidal properties isolated from the fermentation of the bacterium Streptomyces avermitilis. The value of ivermectin in the dermatological field lies in its ability to reduce redness and papules and pustules, characteristic symptoms of papulopustular rosacea. Moreover, thanks to its anti-parasitic action, ivermectin also works by suppressing the activity of the mites Demodex Folliculum, whose proliferation is believed to be involved in the development of papulopustular rosacea. Generally, this antibiotic contributes to improving the quality of life of patients suffering from rosacea by reducing the daily embarrassment caused by its various symptoms.

By reducing skin inflammation, ivermectin alleviates erythema and decreases the number of papulopustular lesions.

From a mechanistic perspective, ivermectin works by binding to the glutamate-dependent channels of parasites, including those of Demodex Folliculum. This causes hyperpolarisation of the cells by increasing the membrane permeability to chloride ions, leading to the death of the microorganisms. Furthermore, ivermectin has anti-inflammatory properties at the site of skin lesions. Indeed, it is capable of inhibiting the production of certain pro-inflammatory cytokines by immune cells, such as interleukins 1 and 6 (IL-1 and IL-6) induced by lipopolysaccharide (LPS), thus reducing the redness, papules and pustules characteristic of papulopustular rosacea.

The efficacy of ivermectin in combating papulopustular rosacea was assessed in two recent identical clinical studies conducted in parallel. Patients were given a formulation containing 1% ivermectin or the same cream without ivermectin. After 12 weeks of daily application, an improvement was observed in 38.4% and 40.1% of patients in the "ivermectin" groups compared to 11.6% and 18.8% in the "placebo" groups. Furthermore, reductions in the numbers of inflammatory lesions of 76.0% and 75.0% for the "ivermectin" groups versus 50.0% for the "placebo" groups were recorded. Ivermectin thus appears to be a promising drug for combating papulopustular rosacea.

Its effectiveness has also been compared to that of metronidazole, commonly used to treat papulopustular rosacea. For this, 962 patients were divided into two groups and received either a 1% ivermectin cream or a 0.75% metronidazole cream. After 16 weeks of daily application, a significant improvement was observed in 84.9% of the patients in the "ivermectin" group, compared to 75.4% of those in the "metronidazole" group. Ivermectin thus appears to be an interesting alternative to metronidazole in the case of papulopustular rosacea.

Are there any side effects and specific usage precautions associated with Ivermectin?

Like all medications, ivermectin can cause side effects. However, these are relatively infrequent. Indeed, around 1% of patients who use it to treat their papulopustular rosacea report a burning sensation and slight irritation. Some have also noticed skin dryness, sometimes accompanied by itching. These discomforts are generally of a mild to moderate intensity and decrease over the course of the treatment.

Another point of caution regarding ivermectin: it can increase the sensitivity of the skin to UV rays. Therefore, it is advised to apply it in the evening, before going to bed. It is also recommended to avoid long sun exposures when the UV index is high and to use daily sun protection. Finally, the application of ivermectin is generally not recommended for pregnant and breastfeeding women as it may pose a neurotoxic risk.