> ## Documentation Index > Fetch the complete documentation index at: https://docs.hi-doctor.ai/llms.txt > Use this file to discover all available pages before exploring further. # Topical metronidazole — rosacea papules > Metronidazole 0.75% is a long-established topical for papulopustular rosacea. How it works, what it does not do, and where it sits in the compounded formulas. Topical metronidazole is one of the longest-established treatments for papulopustular rosacea. It is a nitroimidazole, and although it is an antimicrobial when taken systemically, the benefit in rosacea appears to come from something else entirely. ## What it is Active ingredient: **metronidazole 0.75%**. On this service it is not prescribed as a single agent. It appears at 0.75% in both compounded formulations on the [rosacea](/library/conditions/rosacea) pathway: the erythema cream, alongside [niacinamide](/library/medicines/niacinamide) 4%, micronised [azelaic acid](/library/medicines/azelaic-acid) 10% and allantoin 0.5%; and the papulopustular gel, alongside [ivermectin](/library/medicines/ivermectin-topical) 1% and niacinamide 2%. Both are supplied as 30 g preparations prepared by a pharmacy against the prescription. ## How it works The mechanism in rosacea is not fully established, and the honest position is that it is not primarily antibacterial. The effect that is most consistently invoked is anti-inflammatory: metronidazole suppresses reactive oxygen species generated by neutrophils, and neutrophil-driven oxidative injury is a recognised part of the inflammatory cascade in rosacea. It also appears to modulate the innate immune response in the skin rather than to eliminate an organism. This matters practically. Because the benefit is anti-inflammatory rather than antimicrobial, it acts on the papules and pustules — and leaves the flushing, the fixed background erythema and the visible vessels largely as they were. Setting that expectation is most of the difference between a treatment people stay on and a treatment they abandon at week six. Inflammatory papules and pustules of the central face. This is the phenotype it has the strongest track record against, and the one an online topical consultation is best placed to address. It does not remove telangiectasia, does not reverse phymatous change, and does little for the background redness. Vessels and phymatous disease are handled with light-based or surgical treatment in person. ## What has been reported Topical metronidazole is generally among the better-tolerated rosacea topicals, which is part of why it has lasted. | Reported effect | Character | | -------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------- | | Dryness and scaling | Common; usually mild | | Burning, stinging or itching on application | Common early, generally milder than with azelaic acid | | Erythema and skin irritation | Common; disproportionate or spreading redness is a reason to stop and seek advice | | Contact dermatitis | Uncommon; distinguished from ordinary irritation by intense itch and spread beyond the application area | | Worsening of rosacea | Reported, and worth taking seriously — a flare that begins after starting a new product is a reason to message the doctor rather than push on | | Metallic taste, nausea, numbness or tingling | Reported very rarely with topical use. Systemic absorption from a topical is low, but these are the systemic effects associated with the molecule | The interaction between systemic metronidazole and alcohol — the disulfiram-like reaction — is a feature of oral treatment. Systemic absorption from a topical preparation is minimal. It is still worth mentioning to the reviewing doctor if you have had a reaction to metronidazole before, in any form. ## Realistic timelines Local tolerance is established. Mild stinging or dryness is common and usually settles. Inflammatory papules and pustules typically begin to reduce. Background erythema is usually unchanged at this stage, which is expected rather than a failure. The fair point of assessment for the inflammatory component. Rosacea relapses when treatment stops. Maintenance at a reduced frequency is the usual approach, and the reviewing doctor decides what that looks like. ## Who it is not suitable for Anyone with known hypersensitivity to metronidazole, to other nitroimidazoles or to an excipient in the formulation. It is kept away from the eyes, and any eye symptom in rosacea — grittiness, burning, recurrent styes, lid inflammation — is a reason for an eye assessment rather than a facial cream. Suitability in pregnancy and breastfeeding is a decision for the reviewing doctor, who needs to know before prescribing. ## How Hi-Doctor handles it The review is fully asynchronous — no video call, no telephone consultation. You complete the rosacea questionnaire, upload the required photograph, and a registered doctor works out which phenotype is present and decides whether a compounded topical is appropriate. A prescription is never guaranteed; if one is not issued, the consultation fee is refunded in full. The preparation is dispensed and paid for at a pharmacy — the [pricing page](/essentials/pricing) covers what the consultation fee includes. ## Related reading * [Rosacea](/library/conditions/rosacea) * [Ivermectin](/library/medicines/ivermectin-topical) · [azelaic acid](/library/medicines/azelaic-acid) · [niacinamide](/library/medicines/niacinamide) * [How to apply a prescription topical](/library/guides/how-to-apply-topicals) * [Side effects of dermatology topicals](/library/guides/side-effects-dermatology) * [Taking your dermatology photos](/library/guides/dermatology-photos) * [Safety and eligibility](/essentials/safety) ## Start a consultation Answer the rosacea questionnaire and upload the required photograph. A registered doctor reviews the case and decides whether a topical treatment is appropriate — declining is a normal outcome. See [what it costs](/essentials/pricing) and [how the review works](/essentials/how-it-works). This page is reference information, not medical advice and not a prescription. Whether a medicine is appropriate for you is decided by a registered doctor after reviewing your consultation.