Description

Overview

Metronidazole is a nitroimidazole antibiotic and anti-inflammatory agent commonly used to treat rosacea, bacterial skin infections, and other inflammatory dermatological conditions. It is available in topical gel, cream, or lotion formulations and is well-tolerated by most patients.

Mechanism of Action

• Antibacterial Effect: Metronidazole disrupts bacterial DNA synthesis, leading to bacterial cell death. While its exact mechanism in rosacea is not fully understood, it is believed to reduce overgrowth of Demodex mites and certain anaerobic bacteria on the skin.
• Anti-Inflammatory Action: Inhibits reactive oxygen species (ROS) and reduces inflammatory cytokines, helping to control redness and swelling in rosacea.

Benefits and Indications

1. Rosacea (First-Line Treatment)

• Reduces redness, papules, and pustules associated with papulopustular rosacea.
• Helps control flushing and inflammatory skin responses.

2. Perioral Dermatitis (Off-Label Use)

• Effective in managing the redness and bumps around the mouth and nose.

3. Wound Healing & Post-Surgical Care

• Sometimes used to prevent bacterial infections in chronic wounds and pressure ulcers.

4. Hidradenitis Suppurativa (Off-Label)

• Helps control inflammation and secondary bacterial infections.

Possible Side Effects

• Common: Mild dryness, itching, redness, and burning sensation.
• Less Common: Skin irritation, stinging, or worsening of rosacea symptoms initially.
• Rare but Serious: Allergic reactions (rash, swelling, severe irritation).

Drug Interactions

• Alcohol (Ethanol): Although topical use has minimal systemic absorption, disulfiram-like reactions (nausea, flushing, headaches) are theoretically possible.
• Other Topical Irritants (Retinoids, Benzoyl Peroxide, Astringents): May increase dryness or irritation when used together.

Special Considerations

• Pregnancy Category B: Generally safe for use during pregnancy, but consult a doctor before use.
• Not Effective for Telangiectasia (Visible Blood Vessels): Works on inflammation but does not reduce broken blood vessels in rosacea.
• Best for Mild to Moderate Rosacea: May be used alone or with azelaic acid, ivermectin, or oral antibiotics for severe cases.