Treatment of rosacea with i% metronidazole cream. A double-blind study

Microencapsulated Benzoyl Peroxide for Rosacea in Context: A Review of the Current Treatment Landscape

Rosacea, a chronic skin condition affecting millions of people in the USA, leads to significant social and professional stigmatization. Effective management strategies are crucial to alleviate symptoms and improve patients' quality of life. Encapsulated benzoyl peroxide 5% (E-BPO 5%) is a newly FDA-approved topical treatment for rosacea that shows promise in enhancing therapeutic response and minimizing skin irritation. This review aims to assess the role of recently FDA approved E-BPO 5% in the current treatment landscape for rosacea management, as it is not yet included in clinical guidelines that predominantly rely on older approved therapies. The review focuses on randomized controlled trials conducted in English-speaking adults. It evaluates the efficacy, safety, and tolerability of various US Food and Drug Administration (FDA)-approved agents used for rosacea treatment, including E-BPO cream, metronidazole gel, azelaic acid gel and foam, ivermectin cream, minocycline foam, oral doxycycline, brimonidine gel, and oxymetazoline HCl cream. Existing therapies have been effective in reducing papulopustular lesions and erythema associated with rosacea for many years. E-BPO 5% offers a promising addition to the treatment options due to its microencapsulation technology, which prolongs drug delivery time and aims to improve therapeutic response while minimizing skin irritation. Further research is necessary to determine the exact role of E-BPO 5% in the therapeutic landscape for rosacea. However, based on available evidence, E-BPO 5% shows potential as a valuable treatment option for managing inflammatory lesions of rosacea, and it may offer benefits to patients including: rapid onset of action, demonstrated efficacy by Week 2, excellent tolerability, and sustained long-term results for up to 52 weeks of treatment.

Rosacea: Practical Guidance and Challenges for Clinical Management

Rosacea is a common chronic dermatosis. Clinically, rosacea can present with flushing, erythema, papules, pustules, telangiectasias, phymatous changes, pruritus, burning, and stinging. In 2017, the National Rosacea Society Expert Committee recommended a phenotype-based classification for therapy. In this review, we identify monotherapies and multimodal treatment approaches for the clinical management of rosacea including topical, systemic, laser and light, alternative, and combination therapies.

Efficacy and safety of antibiotic agents in the treatment of rosacea: a systemic network meta-analysis

Background: Antibiotics are considered the backbone of rosacea management, especially for controlling inflammatory papules and pustules. We aim to evaluate the efficacy and safety of varied prescriptions and doses of antibiotics in treating rosacea by network meta-analysis. Methods: In this study, we compared all available randomized controlled trials (RCTs) that have studied systemic and topical antibiotics and placebo in rosacea therapy. We searched databases such as the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, PubMed, Web of Science, and LILACS for published and unpublished RCTs on ClinicalTrials.gov before April 2023. The primary outcome was the improvement of the Investigator's Global Assessment (IGA) scores, and the secondary outcomes consisted of the improvement of the Patient's Global Assessment (PaGA) scores, Clinician's Erythema Assessment (CEA) scores, and adverse events (AEs). We used Bayesian random effects models for multiple treatment comparisons. Results: We identified 1,703 results through these databases. Thirty-one randomized trials with 8,226 patients were included. The heterogeneity and inconsistency between the trials were low, with a low risk of bias of all trials. Oral doxycycline 40 mg, minocycline 100 mg, and minocycline 40 mg, as well as topical ivermectin and metronidazole 0.75%, were effective in treating papules and pustules, thereby decreasing IGA in rosacea. Among these, minocycline 100 mg ranked top in efficacy. As for improving the PaGA scores, topical ivermectin, metronidazole 1%, and systemic oxytetracycline were effective, of which oxytetracycline worked the best. Both doxycycline 40 mg and metronidazole 0.75% presented no therapeutic effect for erythema. Considering the safety of the agents, systemic application of azithromycin and doxycycline 100 mg significantly increase the risk of AEs. Conclusion: Our review suggests that a high dosage of systemic minocycline is the most effective in treating rosacea phenotypes with papules and pustules with a low risk of AEs. However, there were no sufficient evidence-based data in exploring the influence of antibiotics on erythema. The phenotype of rosacea should be taken into consideration along with benefit and safety when making prescriptions due to AEs. Clinical Trial Registration: NCT(2016): http://cochranelibrary-wiley.com/o/cochrane/clcentral/articles/962/CN-01506962/frame.html NCT(2017): http://cochranelibrary-wiley.com/o/cochrane/clcentral/articles/764/CN-01565764/frame.html.

Topical Antibiotic Treatment in Dermatology

Many indications in dermatology can be effectively managed with topical antibiotics, including acne vulgaris, wound infections, secondarily infected dermatitis, and impetigo. Dermatologists must be familiar with the wide spectrum of topical antibiotics available, including indications, mechanisms of action, adverse events, and spectra of activity. Dermatologists must also keep antibiotic resistance in mind when utilizing these medications. Due to the widespread use of topical antibiotics and their importance in dermatology, a literature review was performed using a systematic search of PubMed and Google Scholar with the terms topical antibiotics, skin infections, dermatology, antimicrobials, and inflammatory dermatoses to identify English-language articles published between 1965-2022 from any country. Relevant publications were manually reviewed for additional content. The following literature review will summarize the common topical antibiotics used in dermatology.

Rosacea Management: A Comprehensive Review

Rosacea is a chronic cutaneous disorder affecting primarily the face, characterized by erythema, transient or persistent, telangiectasia, and inflammatory lesions including papulo-pustules and swelling. The essential component of the disease is the persistent erythema of facial skin. Episodes of flushing (acute-subacute intermittent vasodilation) are common. Swelling and erythema of the nose along with dilatation of the pilosebaceous poral orifices, known as rhinophyma, can be noted in chronic cases. Rosacea affects up to 10% of the world population and is especially noted in fair skinned individuals aged 35 to 50. Women are affected more often than men. Several treatment modalities including topical medications, systemic drugs, lasers and light-based therapies have been used for the management of rosacea with variable results. Topical medications such as azelaic acid, metronidazole, and sulfacetamide/sulphur, oral antibiotics such as tetracyclines, and oral retinoids alone or, most commonly, in combination form the mainstay of treatment. Light therapies such as intense pulsed light and pulsed dye laser are best used for the eythemato-telangiectatic type. Topical brimonidine, oxymetazoline, ivermectin, tacrolimus, pimercrolimus, low-dose modified release tetracyclines and botulinum toxin are the new additions to the therapeutic armamentarium. This article provides a comprehensive review of the various therapies used for rosacea.

Metronidazole gel (0.75%) in Japanese patients with rosacea: A randomized, vehicle-controlled, phase 3 study

Topical metronidazole is not currently approved in Japan as a treatment for the indication of rosacea, although 0.75% metronidazole gel was authorized in 2014 for the management of cancerous skin ulcers. We conducted a randomized, double-blind, vehicle-controlled study to evaluate the efficacy and safety of 0.75% metronidazole gel in Japanese patients with inflammatory lesions (papules/pustules) and erythema associated with moderate to severe rosacea. Overall, 130 patients were randomly assigned to receive 0.75% metronidazole gel (n = 65) or vehicle (n = 65), and 120 patients completed 12 weeks of treatment. The primary efficacy outcome was the proportion of patients who achieved both of the following at week 12: an improvement of >50% in the number of inflammatory lesions (papules/pustules) and a positive change of at least one degree in erythema severity. This composite outcome was achieved by 72.3% of metronidazole-treated patients versus 36.9% of vehicle-treated patients, with the between-group difference demonstrating significant improvement with 0.75% metronidazole gel (p < 0.0001). All secondary efficacy endpoints (patients achieving a score of ≥3 for percent change in the number of inflammatory lesions at week 12; patients achieving a score of ≥3 for change in erythema severity at week 12; patients achieving an Investigator's Global Assessment score of 0 or 1 at week 12; percent change over time in the number of inflammatory lesions; change over time in erythema severity) also showed improvement in the 0.75% metronidazole gel group. The incidence of adverse events was higher with metronidazole (40.0%) than with vehicle (29.2%). Of these, treatment-related, treatment-emergent adverse events occurred in 9.2% and 6.2% in the metronidazole and the vehicle group, respectively, but there were no new safety concerns. Overall, the results of this study have confirmed the efficacy and safety of 0.75% metronidazole gel in Japanese patients with rosacea.

Standard management options for rosacea: The 2019 update by the National Rosacea Society Expert Committee

In 2017, a National Rosacea Society Expert Committee developed and published an updated classification of rosacea to reflect current insights into rosacea pathogenesis, pathophysiology, and management. These developments suggest that a multivariate disease process underlies the various clinical manifestations of the disorder. The new system is consequently based on phenotypes that link to this process, providing clear parameters for research and diagnosis as well as encouraging clinicians to assess and treat the disorder as it may occur in each individual. Meanwhile, a range of therapies has become available for rosacea, and their roles have been increasingly defined in clinical practice as the disorder has become more widely recognized. This update is intended to provide a comprehensive summary of management options, including expert evaluations, to serve as a guide for tailoring treatment and care on an individual basis to achieve optimal patient outcomes.

Interventions for rosacea based on the phenotype approach: an updated systematic review including GRADE assessments

BACKGROUND

Rosacea is a common chronic facial dermatosis. Classification of rosacea has evolved from subtyping to phenotyping.

OBJECTIVES

To update our systematic review on interventions for rosacea.

METHODS

We searched CENTRAL, MEDLINE, Embase, LILACS, Science Citation Index and ongoing trials registers (March 2018) for randomized controlled trials. Study selection, data extraction, risk-of-bias assessment and analyses were carried out independently by two authors. Grading of Recommendations, Assessment, Development and Evaluations (GRADE) was used to assess certainty of evidence.

RESULTS

We included 152 studies (46 were new), comprising 20 944 participants. Topical interventions included brimonidine, oxymetazoline, metronidazole, azelaic acid, ivermectin and other topical treatments. Systemic interventions included oral antibiotics, combinations with topical treatments or other systemic treatments. Several studies evaluated laser or light-based treatment. We present the most current evidence for rosacea management based on a phenotype-led approach.

CONCLUSIONS

For reducing temporarily persistent erythema there was high-certainty evidence for topical brimonidine and moderate certainty for topical oxymetazoline; for erythema and mainly telangiectasia there was low-to-moderate-certainty evidence for laser and intense pulsed light therapy. For reducing papules/pustules there was high-certainty evidence for topical azelaic acid and topical ivermectin; moderate-to-high-certainty evidence for doxycycline 40 mg modified release (MR) and isotretinoin; and moderate-certainty evidence for topical metronidazole, and topical minocycline and oral minocycline being equally effective as doxycycline 40 mg MR. There was low-certainty evidence for tetracycline and low-dose minocycline. For ocular rosacea, there was moderate-certainty evidence that oral omega-3 fatty acids were effective and low-certainty evidence for ciclosporin ophthalmic emulsion and doxycycline.

Swiss S1 guideline for the treatment of rosacea

Rosacea (in German sometimes called 'Kupferfinne', in French 'Couperose' and in Italian 'Copparosa') is a chronic and frequently relapsing inflammatory skin disease primarily affecting the central areas of the face. Its geographic prevalence varies from 1% to 22%. The differential diagnosis is wide, and the treatment is sometimes difficult and varies by stage of rosacea. For erythematous lesions and telangiectasia, intense pulsed light (IPL) therapy and lasers are popular treatment option. In addition, a vasoconstrictor agent, brimonidine, has recently been developed. For papulopustular rosacea, topical antibiotics, topical and systemic retinoids, as well as systemic antibiotics are used. A topical acaricidal agent, ivermectin, has undergone clinical development and is now on the market. In the later stages, hyperplasia of the sebaceous glands develops, resulting in phymatous growths such as the frequently observed bulbous nose or rhinophyma. Ablative laser treatments have largely replaced classical abrasive tools. Here, we reviewed the current evidence on the treatment of rosacea, provide a guideline (S1 level) and discuss the differential diagnosis of rosacea.

Randomized Placebo-Controlled Trial of Metronidazole 1 % Cream with Sunscreen SPF 15 in Treatment of Rosacea

Background:

Rosacea is a photoaggravated dermatosis responsive to treatment with topical and oral antibiotics. A formulation combining metronidazole 1% cream with sunscreen SPF 15 was developed for the treatment of rosacea. Objective: The objective of this study was to determine the safety and efficacy of a formulation combining metronidazole 1% cream with sunscreen SPF 15 in the treatment of moderate to severe rosacea.

Methods:

One hundred and twenty patients with moderate to severe rosacea were enrolled for a randomized, placebo-controlled (vehicle containing sunscreen with SPF 15), double-blind study. Study cream was applied twice daily to the entire face over a 12-week period.

Results:

Treatment with metronidazole 1% cream with sunscreen SPF 15 resulted in significant improvement ( p < 0.05) in inflammatory lesion count, erythema and telangiectasiae scores, and investigator and patient global assessment scores compared with baseline and placebo. Adverse reactions related to study medication were typically mild, occurred at the site of application, and were reversible. There was no difference between the safety profiles of metronidazole 1% cream with sunscreen SPF 15 and placebo.

Conclusions:

The combined topical formulation of metronidazole 1% cream with sunscreen SPF 15 was an effective, well-tolerated topical agent for the treatment of moderate to severe rosacea.

Canadian Clinical Practice Guidelines for Rosacea

Rosacea is a chronic facial inflammatory dermatosis characterized by background facial erythema and flushing and may be accompanied by inflammatory papules and pustules, cutaneous fibrosis and hyperplasia known as phyma, and ocular involvement. These features can have adverse impact on quality of life, and ocular involvement can lead to visual dysfunction. The past decade has witnessed increased research into pathogenic pathways involved in rosacea and the introduction of novel treatment innovations. The objective of these guidelines is to offer evidence-based recommendations to assist Canadian health care providers in the diagnosis and management of rosacea. These guidelines were developed by an expert panel of Canadian dermatologists taking into consideration the balance of desirable and undesirable outcomes, the quality of supporting evidence, the values and preferences of patients, and the costs of treatment. The 2015 Cochrane review "Interventions in Rosacea" was used as a source of clinical trial evidence on which to base the recommendations.

Rosacea: diagnostics and treatment

The authors present current data from the literature relating to major characteristics and efficacy of methods of non-invasive diagnostics of rosacea (dermatoscopy, dopplerography, ultrasound scanning, confocal laser scanning microscopy) as well as aspects of a systemic external therapy, laser therapy and use of IPL systems in the treatment of patients suffering from rosacea.

Interventions for rosacea

BACKGROUND

Rosacea is a common chronic skin condition affecting the face, characterised by flushing, redness, pimples, pustules and dilated blood vessels. The eyes are often involved and thickening of the skin with enlargement (phymas), especially of the nose, can occur in some people. A range of treatment options are available but it is unclear which are most effective.

OBJECTIVES

To assess the efficacy and safety of treatments for rosacea.

SEARCH METHODS

We updated our searches, to July 2014, of: the Cochrane Skin Group Specialised Register, CENTRAL in The Cochrane Library (2014, Issue 6), MEDLINE (from 1946), EMBASE (from 1974) and Science Citation Index (from 1988). We searched five trials registers and checked reference lists for further relevant studies.

SELECTION CRITERIA

Randomised controlled trials in people with moderate to severe rosacea.

DATA COLLECTION AND ANALYSIS

Study selection, data extraction, risk of bias assessment and analyses were carried out independently by two authors.

MAIN RESULTS

We included 106 studies, comprising 13,631 participants. Sample sizes of 30-100 and study duration of two to three months were most common. More women than men were included, mean age of 48.6 years, and the majority had papulopustular rosacea, followed by erythematotelangiectatic rosacea.A wide range of comparisons (67) were evaluated. Topical interventions: metronidazole, azelaic acid, ivermectin, brimonidine or other topical treatments. Systemic interventions: oral antibiotics, combinations with topical treatments or other systemic treatments, i.e. isotretinoin. Several studies evaluated laser or light-based treatment.The majority of studies (57/106) were assessed as 'unclear risk of bias', 37 'high risk ' and 12 'low risk'. Twenty-two studies provided no usable or retrievable data i.e. none of our outcomes were addressed, no separate data reported for rosacea or limited data in abstracts.Eleven studies assessed our primary outcome 'change in quality of life', 52 studies participant-assessed changes in rosacea severity and almost all studies addressed adverse events, although often only limited data were provided. In most comparisons there were no statistically significant differences in number of adverse events, most were mild and transient. Physician assessments including investigators' global assessments, lesion counts and erythema were evaluated in three-quarters of the studies, but time needed for improvement and duration of remission were incompletely or not reported.The quality of the body of evidence was rated moderate to high for most outcomes, but for some outcomes low to very low.Data for several outcomes could only be pooled for topical metronidazole and azelaic acid. Both were shown to be more effective than placebo in papulopustular rosacea (moderate quality evidence for metronidazole and high for azelaic acid). Pooled data from physician assessments in three trials demonstrated that metronidazole was more effective compared to placebo (risk ratio (RR) 1.98, 95% confidence interval (CI) 1.29 to 3.02). Four trials provided data on participants' assessments, illustrating that azelaic acid was more effective than placebo (RR 1.46, 95% CI 1.30 to 1.63). The results from three studies were contradictory on which of these two treatments was most effective.Two studies showed a statistically significant and clinically important improvement in favour of topical ivermectin when compared to placebo (high quality evidence). Participants' assessments in these studies showed a RR of 1.78 (95% CI 1.50 to 2.11) and RR of 1.92 (95% CI 1.59 to 2.32),which were supported by physicians' assessments. Topical ivermectin appeared to be slightly more effective than topical metronidazole for papulopustular rosacea, based on one study, for improving quality of life and participant and physician assessed outcomes (high quality evidence for these outcomes).Topical brimonidine in two studies was more effective than vehicle in reducing erythema in rosacea at all time points over 12 hours (high quality evidence). At three hours the participants' assessments had a RR of 2.21 (95% CI 1.52 to 3.22) and RR of 2.00 (95% CI 1.33 to 3.01) in favour of brimonidine. Physicians' assessments confirmed these data. There was no rebound or worsening of erythema after treatment cessation.Topical clindamycin phosphate combined with tretinoin was not considered to be effective compared to placebo (moderate quality evidence).Topical ciclosporin ophthalmic emulsion demonstrated effectiveness and improved quality of life for people with ocular rosacea (low quality evidence).Of the comparisons assessing oral treatments for papulopustular rosacea there was moderate quality evidence that tetracycline was effective but this was based on two old studies of short duration. Physician-based assessments in two trials indicated that doxycycline appeared to be significantly more effective than placebo (RR 1.59, 95% CI 1.02 to 2.47 and RR 2.37, 95% CI 1.12 to 4.99) (high quality evidence). There was no statistically significant difference in effectiveness between 100 mg and 40 mg doxycycline, but there was evidence of fewer adverse effects with the lower dose (RR 0.25, 95% CI 0.11 to 0.54) (low quality evidence). There was very low quality evidence from one study (assessed at high risk of bias) that doxycycline 100 mg was as effective as azithromycin. Low dose minocycline (45 mg) was effective for papulopustular rosacea (low quality evidence).Oral tetracycline was compared with topical metronidazole in four studies and showed no statistically significant difference between the two treatments for any outcome (low to moderate quality evidence).Low dose isotretinoin was considered by both the participants (RR 1.23, 95% CI 1.05 to 1.43) and physicians (RR 1.18, 95% CI 1.03 to 1.36) to be slightly more effective than doxycycline 50-100 mg (high quality evidence).Pulsed dye laser was more effective than yttrium-aluminium-garnet (Nd:YAG) laser based on one study, and it appeared to be as effective as intense pulsed light therapy (both low quality evidence).

AUTHORS' CONCLUSIONS

There was high quality evidence to support the effectiveness of topical azelaic acid, topical ivermectin, brimonidine, doxycycline and isotretinoin for rosacea. Moderate quality evidence was available for topical metronidazole and oral tetracycline. There was low quality evidence for low dose minocycline, laser and intense pulsed light therapy and ciclosporin ophthalmic emulsion for ocular rosacea. Time needed to response and response duration should be addressed more completely, with more rigorous reporting of adverse events. Further studies on treatment of ocular rosacea are warranted.

Preparation and evaluation of topical microemulsion system containing metronidazole for remission in rosacea

The aim of this study was to prepare a topical water-in-oil type microemulsion containing metronidazole and to compare its effectiveness with a commercial gel product in the treatment of rosacea. A pseudo-ternary phase diagram (K(m)=2:1) was constructed using lecithin/butanol/isopropyl myristate/water. The microemulsion was chosen from the microemulsion region in the phase diagram. The formulation was a water-in-oil type microemulsion (droplet size: 11.6 nm, viscosity: 457.3 mPa·s, conductivity: 1.5 µs/cm, turbidity: 6.89 NTU) and the addition of the metronidazole did not alter the properties of the system. The release experiment showed that the release rate of metronidazole from the commercial gel product was higher than that of the microemulsion. Stability experiments showed that the metronidazole microemulsion remained stable for at least 6 months; none of the characteristic properties of the microemulsion had changed, the system retained its clarity and there was no sign that crystallization of metronidazole has occurred. Microemulsion was compared to a gel product in a randomized, double-blind, baseline-controlled, split-face clinical trial for the treatment of patients. After the 6-week treatment period there was a statistically significant difference in reduction of the main symptoms of rosacea. Of the patients treated with the microemulsion, 17% experienced complete relief from inflammatory lesions, and 50% from erythema. The microemulsion resulted in complete relief in 38% of the patients with telangiectasia while the commercial product did not provide any relief of telangiectasia symptoms. In conclusion, the microemulsion containing metronidazole was found to be more effective in reducing the symptoms of rosacea compared to the commercial gel product.

Effective and evidence-based management strategies for rosacea: summary of a Cochrane systematic review

Rosacea is a common chronic skin disease affecting the face. There are numerous treatment options, but it is unclear which are the most effective. The aim of this review was to assess the evidence for the efficacy and safety of treatments for rosacea. Searches included the Cochrane Skin Group Specialised Register, the Cochrane Central Register of Controlled Trials in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index, and Ongoing Trials Registers (updated February 2011). Randomized controlled trials in people with moderate to severe rosacea were included. Fifty-eight trials, including 27 from the original review, comprising 6633 participants were included in this updated review. Interventions included topical metronidazole, oral antibiotics, topical azelaic cream or gel, topical benzoyl peroxide and/or combined with topical antibiotics, sulphacetamide/sulphur, and others. There was some evidence that topical metronidazole and azelaic acid were more effective than placebo. Two trials indicated that doxycycline 40mg was more effective than placebo. There was no statistically significant difference in effectiveness between doxycycline 40mg and 100mg but there were fewer adverse effects. One study reported that ciclosporin ophthalmic emulsion was significantly more effective than artificial tears for treating ocular rosacea. Although the majority of included studies were assessed as being at high or unclear risk of bias, there was some evidence to support the effectiveness of topical metronidazole, azelaic acid and doxycycline (40mg) in the treatment of moderate to severe rosacea, and ciclosporin 0·05% ophthalmic emulsion for ocular rosacea. Further well-designed, adequately powered randomized controlled trials are required.

Interventions for rosacea

BACKGROUND

Rosacea is a common chronic skin condition affecting the face, characterised by flushing, redness, pimples, pustules, and dilated blood vessels. The eyes are often involved and thickening of the skin with enlargement (phymas), especially of the nose, can occur in some patients. A range of treatment options are available but it is unclear which are the most effective.

OBJECTIVES

To assess the evidence for the efficacy and safety of treatments for rosacea.

SEARCH STRATEGY

In February 2011 we updated our searches of the Cochrane Skin Group Specialised Register, the Cochrane Central Register of Controlled Trials (Clinical Trials) in The Cochrane Library, MEDLINE, EMBASE, Science Citation Index, and Ongoing Trials Registers.

SELECTION CRITERIA

Randomised controlled trials in people with moderate to severe rosacea.

DATA COLLECTION AND ANALYSIS

Study selection, data extraction, assessment of risk of bias, and analyses were carried out by two independent review authors.

MAIN RESULTS

Fifty-eight trials, including 27 from the original review, comprising 6633 participants were included in this updated review. Interventions included topical metronidazole, oral antibiotics, topical azelaic cream or gel, topical benzoyl peroxide and/or combined with topical antibiotics, sulphacetamide/sulphur, and others. Only two studies assessed our primary outcome 'quality of life'.Pooled data from physician assessments in three trials provided some evidence that metronidazole was more effective compared to placebo (RR 1.95, 95% CI 1.48 to 2.56). Three trials provided data, based on participants' assessments, illustrating azelaic acid was more effective than placebo (RR 1.52, 95% CI 1.32 to 1.76).Physician-based assessments in two trials indicated that doxycycline appeared to be significantly more effective than placebo (RR 1.59, 95% CI 1.02 to 2.47 and RR 2.37, 95% CI 1.12 to 4.99). There was no statistically significant difference in effectiveness between 100 mg and 40 mg doses of doxycycline, but there was evidence of less adverse effects with the lower dose (RR 0.25, 95% CI 0.11 to 0.54).One study reported that cyclosporine ophthalmic emulsion was significantly more effective than artificial tears for treating ocular rosacea (for all outcomes).

AUTHORS' CONCLUSIONS

Although the majority of included studies were assessed as being at high or unclear risk of bias there was some evidence to support the effectiveness of topical metronidazole, azelaic acid, and doxycycline (40 mg) in the treatment of moderate to severe rosacea, and cyclosporine 0.5% ophthalmic emulsion for ocular rosacea. Further well-designed, adequately-powered randomised controlled trials are required.

Systematic review of rosacea treatments

BACKGROUND

Rosacea is a common chronic skin and ocular condition. It is unclear which treatments are most effective. We have conducted a Cochrane review of rosacea therapies. This article is a distillation of that work.

OBJECTIVE

We sought to assess the evidence for the efficacy and safety of rosacea therapies.

METHODS

Multiple databases were systematically searched. Randomized controlled trials in people with moderate to severe rosacea were included. Study selection, assessment of methodologic quality, data extraction, and analysis were carried out by two independent researchers.

RESULTS

In all, 29 studies met inclusion criteria. Topical metronidazole is more effective than placebo (odds ratio 5.96, 95% confidence interval 2.95-12.06). Azelaic acid is more effective than placebo (odds ratio 2.45, 95% confidence interval 1.82-3.28). Firm conclusions could not be drawn about other therapies.

LIMITATIONS

The quality of the studies was generally poor.

CONCLUSIONS

There is evidence that topical metronidazole and azelaic acid are effective. There is some evidence that oral metronidazole and tetracycline are effective. More well-designed, randomized controlled trials are required to provide better evidence of the efficacy and safety of other rosacea therapies.

Rosazea

Rosacea is a common facial dermatosis, which may have detrimental effects on the patient's psychological and social interactions. It is a disease of the middle aged, skin types I and II are more often affected than darker skin types. Clinically, pre-rosacea, and rosacea grade I-III may be distinguished. Pre-rosacea is characterized by flushing and blushing, grade I to III by erythemato-teleangiectasies, papulopustules, and inflammatory nodules. Especially severe subtypes include rosacea conglobata and rosacea fulminans. Hyperglandular subtypes lead to different forms of phyma, of which Rhinophyma is the most frequent. Pathogenetically destruction of the dermal vessels and connective tissue seems to be decisive for the development of a chronic inflammation, which leads to the phenotype of the various forms of rosacea. Mild forms can be treated exclusively by topical medication. Antibiotics (erythromycin, clindamycin, tetracyclin), metronidazol, azelaic acid, and the retinoid adapalene have been shown to be effective in well controlled randomized studies. The best evaluated topical medication is metronidazol. In severe forms systemic therapy must be applied. Systemic antibiotics are effective and especially isotretinoin has shown a very good response even in low dose regimens. Rhinophyma must be treated surgically.

Interventions for rosacea

BACKGROUND

Rosacea is a common chronic skin condition affecting the face, characterised by flushing, redness, pimples, pustules, and dilated blood vessels. The eyes are often involved. Frequently it can be controlled, but it is not clear which treatments are most effective.

OBJECTIVES

To assess the evidence for the efficacy and safety of treatments for rosacea.

SEARCH STRATEGY

We searched the Skin Group Specialised Register (February 2005), Cochrane Central Register of Controlled Trials (The Cochrane Library Issue 1, 2005), MEDLINE (1966 to February 2005), EMBASE (1980 to February 2005), BIOSIS (1970 to March 2002) and the Science Citation Index (1988 to February 2005). Reference lists of trials and key review articles were searched. Relevant manufacturers and experts were contacted.

SELECTION CRITERIA

Randomised controlled trials in people with moderate to severe rosacea were included. Studies judged by the authors to have seriously flawed methodology were excluded.

DATA COLLECTION AND ANALYSIS

Study selection, assessment of methodological quality, data extraction and analysis were carried out by two independent authors. Disagreements were resolved by discussion and consensus.

MAIN RESULTS

The evidence provided by twenty-nine included studies was generally weak because of poor methodology and reporting. One of our primary outcome measures, 'quality of life', was not assessed in any of the studies. Only two studies of ocular rosacea were included. Pooled data from two trials involving 174 participants indicated that according to the participants, topical metronidazole is more effective than placebo (odds ratio (OR) 5.96, 95% confidence interval (CI) 2.95 to 12.06). Data pooled from three between-patient trials showed a clear improvement in the azelaic acid group; the rates of treatment success were approximately 70 to 80% versus 50% to 55% (OR 2.45, 95% CI 1.82 to 3.28). A within-patient trial of azelaic cream versus placebo could not be pooled with the other three studies, but also showed good evidence of efficacy. Data pooled from three studies of oral tetracycline versus placebo involving 152 participants showed that, according to physicians, tetracycline was effective (OR 6.06, 95% CI 2.96 to 12.42). Some evidence of efficacy of oral metronidazole was provided by one small study.

AUTHORS' CONCLUSIONS

The quality of studies evaluating rosacea treatments was generally poor. There is evidence that topical metronidazole and azelaic acid are effective. There is some evidence that oral metronidazole and tetracycline are effective. There is insufficient evidence concerning the effectiveness of other treatments. Good RCTs looking at these treatments are urgently needed.

Rosacea and its management: an overview

BACKGROUND

Rosacea is a chronic inflammatory disorder that affects 10% of the population. The prevalence of rosacea is highest among fair-skinned individuals, particularly those of Celtic and northern European descent. Since a cure for rosacea does not yet exist, management and treatment regimens are designed to suppress the inflammatory lesions, erythema, and to a lesser extent, the telangiectasia involved with rosacea.

OBJECTIVES

This review outlines the treatment options that are available to patients with rosacea.

METHODS

Published literature involving the treatment or management of rosacea was examined and summarized.

RESULTS

Patients who find that they blush and flush frequently, or have a family history of rosacea are advised to avoid the physiological and environmental stimuli that can cause increased facial redness. Topical agents such as metronidazole, azelaic acid cream or sulfur preparations are effective in managing rosacea. Patients who have progressed to erythematotelangiectatic and papulopustular rosacea may benefit from the use of an oral antibiotic, such as tetracycline, and in severe or recalcitrant cases, isotretinoin to bring the rosacea flare-up under control. Treatment with a topical agent, such as metronidazole, may help maintain remission. Patients with ocular involvement may benefit from a long-term course of an antibiotic and the use of metronidazole gel. A surgical alternative, laser therapy, is recommended for the treatment of telangiectasias and rhinophyma. Patients with distraught feelings due to their rosacea may consider cosmetic camouflage to cover the signs of rosacea.

CONCLUSIONS

With the wide variety of oral and topical agents available for the effective management of rosacea, patients no longer need to feel self-conscious because of their disorder.

Ocular Rosacea

Rosacea is a common skin disease that frequently involves the eye. Although the pathogenesis of the disease remains undefined, recent findings suggest that an altered inflammatory response plays an important role in both cutaneous and ocular rosacea. Ocular manifestations include lid and ocular surface alterations. Chronic inflammation can lead to corneal vascularization, which may compromise vision. Treatment of ocular rosacea is aimed at preventing irritation of the ocular surface (e.g., lubricants, lid hygiene) and controlling inflammation with topical and systemic anti-inflammatory drugs. Systemic tetracyclines are the mainstay of treatment. These drugs act multifactorially by decreasing bacterial flora and the expression of matrix metalloproteinases, altering meibum secretion, inhibiting the production of bacterial lipases, and providing an immunomodulatory effect.

Measurement of the severity of rosacea

BACKGROUND

There are no standardized measures for the severity of rosacea.

OBJECTIVES

To determine what clinical signs correlate best with global severity of rosacea, and to examine inter-rater reliability. Methods Four clinicians each made 82 assessments of rosacea patients. Each assessment used 60 0-to-10 Likert-like scales for the signs of rosacea. Subjects also assessed the severity of their rosacea.

RESULTS

The clinicians' assessment of global severity correlated strongly with erythema, especially on the cheeks. Subjects' assessment of global severity correlated more strongly with papules/pustules. Different methods of assessing severity--estimation of area involved, intensity, or lesion counts--did not produce significantly different results. Inter-rater reliability was low on 11-point (0-10) scales, but improved when scales were collapsed to 5 or 4 points.

CONCLUSIONS

Clinicians and patients assess severity of rosacea differently, with clinicians focusing on erythema and patients focusing on papules/pustules. New instruments for assessing severity must address inter-rater reliability.

Rosacea: II. Therapy

Despite an incomplete understanding of the pathogenesis of rosacea, therapeutic modalities continue to expand. The principal subtypes of rosacea include erythematotelangiectatic rosacea, papulopustular rosacea, phymatous rosacea, and ocular rosacea. These phenotypic expressions are probably caused by divergent pathogenic factors and consequently respond to different therapeutic regimens. A subtype-directed approach to therapy is discussed in part II of this review. We provide an overview of the available topical, oral, laser, and light therapies in the context of these cutaneous subtypes, review the evidence that supports their use, and outline their therapeutic approach. Suggestions for future areas of study also are provided. Learning objective At the completion of this learning activity, participants should be familiar with the subtype-directed approach to therapy for rosacea including available topical, oral, laser, and light therapies.

Efficiency of benzoyl peroxide-erythromycin gel in comparison with metronidazole gel in the treatment of acne rosacea

Oral wide-spectrum antibiotics are the linchpin of rosacea treatment. Oral and topical metronidazole, topical tretinoin, and topical benzoyl peroxide may also be used in the treatment of rosacea. We aimed to show that benzoyl peroxide-erythromycin gel is efficient in the treatment of acne rosacea. Fifty-six patients with acne rosacea were enrolled in our study. We administered benzoyl peroxide-erythromycin gel to 27 patients and metronidazole gel to 29 patients. In all the patients, the intensities of erythema, telangiectasia, papules/pustules, and nodules were evaluated before, during and after the treatment. The positivity of Demodex folliculorum from skin scratches was compared between the two groups at each visit. At the end of the therapy on the third examination, in the benzoyl peroxide-erythromycin group, 91.7% of the patients showed marked clinical improvement, and 8.3% of them showed complete remission. In the metronidazole group, 73.3% showed marked clinical improvement, and 26.7% of them showed complete remission. Clinical improvement in the papular component was 65.2% for the benzoyl peroxide-erythromycin group, and 81.5% for metronidazole group. In the first examination, the clinical results of the agents were similar. Although both of the drugs were found to be effective in the second and third examinations, metronidazole gel was more effective than benzoyl peroxide-erythromycin. Both of the drugs were found to be significantly effective especially in treating the papular component of rosacea. Demodex folliculorum was found to be positive in 74.1% of the benzoyl peroxide-erythromycin group and in 62.1% of the metronidazole group at the beginning. In the benzoyl peroxide-erythromycin group, 40.7% of Demodex folliculorum positive patients, became negative by the first examination. This was 17.2% for the metronidazole group. In the benzoyl peroxide-erythromycin group, among the patients who were positive for Demodex folliculorum in the first examination, 37.5% of them became negative. This was 36.7% for the metronidazole group. Benzoyl peroxide-erythromycin gel was superior to metronidazole gel in decreasing Demodex folliculorum by the first examination, but the effect of the two drugs on Demodex folliculorum was similar by the second examination. As a result, topically applied combined benzoyl peroxide-erythromycin gel may be an alternative choice of treatment for acne rosacea.

Interventions for rosacea

BACKGROUND

Rosacea is a common skin condition affecting the face, characterised by flushing, redness, pimples, pustules and dilated blood vessels. The eyes are often also involved. The cause of rosacea is unclear. It is a chronic disease, which can be controlled in most cases with appropriate treatment. Numerous treatments are in use although it is unclear which are best, and which are most appropriate for the different types of rosacea.

OBJECTIVES

To assess and summarise current evidence for the efficacy and safety of treatments for rosacea.

SEARCH STRATEGY

We searched the Skin Group Specialised Trials Register (March 2002), Cochrane Central Register of Controlled Trials (CENTRAL, March 2002), MEDLINE (from 1966 to March 2002), EMBASE (from 1980 to March 2002), Biosis (from 1970 to March 2002) and the Science Citation Index (from 1988 to March 2002). Reference lists of trials and key review articles were also searched. Relevant manufacturers and experts were contacted.

SELECTION CRITERIA

Randomised controlled trials in people with moderate to severe rosacea were included. Studies judged by the reviewers to have seriously flawed methodology were excluded.

DATA COLLECTION AND ANALYSIS

Study selection, assessment of methodological quality, data extraction and analysis were carried out by two independent reviewers.

MAIN RESULTS

The evidence provided by twenty-two included studies was generally weak because of poor methodology and reporting. One of our primary outcome measures, 'quality of life', was not assessed in any of the studies. Only two studies of ocular rosacea could be included. Pooled data from two trials involving 174 participants indicated that topical metronidazole is more effective than placebo (odds ratio 5.96, 95% confidence interval 2.95 to 12.06). Data from a between-patient trial (114 patients) and a within-patient trial (33 patients) of azelaic cream versus placebo were not pooled, but both showed good evidence of efficacy. Data pooled from three studies of oral tetracycline versus placebo involving 152 participants showed that, according to physicians' ratings, tetracycline was effective (odds ratio 6.06, 95% confidence interval 2.96 to 12.42). Some evidence of efficacy of oral metronidazole was provided by one small study.

REVIEWER'S CONCLUSIONS

The quality of studies evaluating rosacea treatments was generally poor. There is evidence that topical metronidazole and azelaic acid cream have a therapeutic effect. There is some evidence that oral metronidazole and tetracycline are effective. There is insufficient evidence concerning the effectiveness of other treatments. As many of these treatments are used for rosacea, good RCTs are urgently needed.

Critical review of the manner in which the efficacy of therapies for rosacea are evaluated

BACKGROUND

Rosacea is a relatively common disorder that may affect individuals of all races, particularly those of northern European decent. Its onset generally occurs in individuals between the ages of 20 and 50 years. Rosacea may be classified into four subtypes and one variant. Although individuals with rosacea may not pass through all of the stages, the primary features of the disorder include frequent flushing and blushing, nontransient erythema, the presence of papules and pustules, and telangiectasia. Many agents have been used to treat rosacea stigmata, especially because none of these is uniformly effective.

AIM

To identify the parameters that are used to evaluate the response to therapy when different agents are used to treat rosacea. For a given parameter, to determine whether the different trials are consistent in the manner in which this variable is measured.

METHODS

The reports on the efficacy and safety of the different drug therapies used to treat rosacea were identified. We searched MEDLINE (1966 to June 2002) for studies where rosacea was treated. The parameters used to evaluate the efficacy of therapy were determined. For each parameter, the ways in which it has been measured were identified.

RESULTS

Efficacy of treatment is generally judged by evaluating the effect of the intervention on papules and pustules, erythema, and telangiectasia. Manual lesional counts of papules and pustules are usually performed. There is, however, substantial variation in the methodology chosen for comparison of erythema and telangiectasias. Color scales are popular for erythema and telangiectasia, while grading scales are most commonly used for physician and patient evaluations.

CONCLUSIONS

For each of the parameters that are commonly used to measure the efficacy of treatments for rosacea, the different approaches by which it has been measured in the various trials have been highlighted; these dissimilarities can make it problematic to compare between clinical trials. A greater degree of uniformity in the manner in which the various parameters are evaluated would enable a more objective comparison between the studies.

Use of topical metronidazole in moderate to severe rosacea

Rosacea is a chronic condition requiring long-term therapy for control and maintenance. Numerous controlled studies have shown that metronidazole 0.75% in combination with oral antibiotics significantly reduces the number of papules and pustules and erythema severity scores in patients with severe disease. Topical metronidazole 0.75% also maintains long-term remissions after oral tetracycline has been discontinued. Although original studies involving topical metronidazole 0.75% used a twice-daily regimen, subsequent work has shown that this formulation used once daily is as effective as 1% metronidazole.

Measuring the severity of rosacea: a review

BACKGROUND

Assessment of severity is essential in the clinical care of rosacea patients and in the research on rosacea.

OBJECTIVE

To determine the range of methods used to assess rosacea severity in clinical trials.

METHODS

The medical literature from 1965 through 2001 was searched for rosacea clinical trials using MEDLINE and published citations. Forty-seven articles were reviewed.

RESULTS

The most frequently assessed signs of rosacea were papules/pustules (43 studies), erythema (35), and telangiectasia (24). Other signs and symptoms of rosacea and adverse reactions to therapies were assessed in 27 studies. Counts of papules/pustules were conducted in 34 studies. Four-point scales were the most frequently used assessment tools for erythema (17) and telangiectasia (11). Other frequently used techniques included global assessment by clinicians (29) and by patients (21), and photography (13).

CONCLUSIONS

At present, there are no standard validated tools for assessing the severity of rosacea or its signs or symptoms.

The role of free oxygen radicals in the aetiopathogenesis of rosacea

A possible link between superoxide dismutase activity and malondialdehyde level with the clinical manifestations of rosacea was investigated. We found differences in superoxide dismutase activities between mild rosacea (stages I and II) and severe involvement (stage III) groups, as well as between disease and control groups that were statistically significant (P < 0.05). In the mild involvement group (stages I and II), the superoxide dismutase activity was higher than in the control group (P < 0.05), while the malondialdehyde levels did not differ from the control. In the severe involvement group (stage III), the superoxide dismutase activity was lower than in the control group (P < 0.05), and this was coupled to a raised level of malondialdehyde (P < 0.05). These findings clearly show that in the mild involvement phase of rosacea patients, superoxide dismutase activity was stimulated to protect the skin against reactive oxygen species so that the malondialdehyde levels were maintained. In contrast, in more severe disease, due to a decrease in the capacity of the antioxidant defence system, the malondialdehyde levels were increased. These findings support the 'antioxidant system defect hypothesis' in rosacea patients.

Effects of metronidazole and tinidazole ointments on models for inflammatory dermatitis in mice

We investigated the effects of 1-4% ointments of metronidazole and tinidazole (derivatives of nitroimidazole) on models of inflammatory dermatitis evoked by antigen, hapten and monoclonal anti-dinitrophenol (DNP) IgE antibody in mice. Metronidazole and tinidazole ointments (1) suppressed the late-phase reaction (LPR) of biphasic ear edema in mice sensitized with ovalbumin (OA), (2) suppressed trinitrochlorobenzene-induced inflammatory dermatitis, (3) suppressed the immediate phase reactions and LPR in mice passively sensitized with anti-DNP IgE mAb, and (4) enhanced vascular permeability and the number of scratching reactions, presumably due to itching, in passively sensitized mice. These results strongly indicate that metronidazole and tinidazole 1-4% ointments possess antiinflammatory, immunosuppressive and anti-itching effects, and have the potential for clinical use in the treatment of human inflammatory skin diseases including atopic dermatitis in addition to rosacea and acne vulgaris.

Metronidazole, its bioactive metabolites and acne

Metronidazole's activity has been established in both acneiform rosacea and acne vulgaris. Recent research indicating that the breakdown products of several antibiotics, including metronidazole, may have considerably greater activity than the parent compound, prompted a re-examination of the susceptibility of Propionibacterium acnes, the organism involved in the fundamental pathogenesis of acne vulgaris. Although the organism was marginally more sensitive to the hydroxy derivative, MIC levels were still outside the readily attainable therapeutic range. The beneficial effects of metronidazole in acne vulgaris are attributable to its anti-inflammatory activities rather than its antibacterial ones.

Metronidazole. A therapeutic review and update

The nitroimidazole antibiotic metronidazole has a limited spectrum of activity that encompasses various protozoans and most Gram-negative and Gram-positive anaerobic bacteria. Metronidazole has activity against protozoans like Entamoeba histolytica, Giardia lamblia and Trichomonas vaginalis, for which the drug was first approved as an effective treatment. Anaerobic bacteria which are typically sensitive are primarily Gram-negative anaerobes belonging to the Bacteroides and Fusobacterium spp. Gram-positive anaerobes such as peptostreptococci and Clostridia spp. are likely to test sensitive to metronidazole, but resistant isolates are probably encountered with greater frequency than with the Gram-negative anaerobes. Gardnerella vaginalis is a pleomorphic Gram-variable bacterial bacillus that is also susceptible to metronidazole. Helicobacter pylori has been strongly associated with gastritis and duodenal ulcers. Classic regimens for eradicating this pathogen have included metronidazole, usually with acid suppression medication plus bismuth and amoxicillin. The activity of metronidazole against anaerobic bowel flora has been used for prophylaxis and treatment of patients with Crohn's disease who might develop an infectious complication. Treatment of Clostridium difficile-induced pseudomembraneous colitis has usually been with oral metronidazole or vancomycin, but the lower cost and similar efficacy of metronidazole, coupled with the increased concern about imprudent use of vancomycin leading to increased resistance in enterococci, have made metronidazole the preferred agent here. Metronidazole has played an important role in anaerobic-related infections. Advantages to using metronidazole are the percentage of sensitive Gram-negative anaerobes, its availability as oral and intravenous dosage forms, its rapid bacterial killing, its good tissue penetration, its considerably lower chance of inducing C. difficile colitis, and expense. Metronidazole has notable effectiveness in treating anaerobic brain abscesses. Metronidazole is a cost-effective agent due to its low acquisition cost, its pharmacokinetics and pharmacodynamics, an acceptable adverse effect profile, and its undiminished antimicrobial activity. While its role as part of a therapeutic regimen for treating mixed aerobic/anaerobic infections has been reduced by newer, more expensive combination therapies, these new combinations have not been shown to have any therapeutic advantage over metronidazole. Although the use of metronidazole on a global scale has been curtailed by newer agents for various infections, metronidazole still has a role for these and other therapeutic uses. Many clinicians still consider metronidazole to be the 'gold standard' antibiotic against which all other antibiotics with anaerobic activity should be compared.

Demodex-associated folliculitis

Examination of 388 follicles in 24 large resections of skin for the presence of histologic folliculitis and Demodex mites uncovered a nonrandom association between these two phenomena. Demodex mites were found in 42% of follicles with inflammation, but in just 10% of the follicles without inflammation. Eighty-three percent of follicles with Demodex showed inflammation. The probability that this result could occur by random chance alone was < 0.001, thus suggesting that Demodex is associated with histologic folliculitis, even minor folliculitis. The results do not, however, decide whether Demodex is causative, whether it preferentially selects follicles with histologic inflammation, or whether some of both processes operate.

Placebo controlled trial of fusidic acid gel and oxytetracycline for recurrent blepharitis and rosacea

A prospective, randomised, double blind, partial crossover, placebo controlled trial has been conducted to compare the performance of topical fusidic acid gel (Fucithalmic) and oral oxytetracycline as treatment for symptomatic chronic blepharitis. Treatment success was judged both by a reduction in symptoms and clinical examination before and after therapy. Seventy five per cent of patients with blepharitis and associated rosacea were symptomatically improved by fusidic acid gel and 50% by oxytetracycline, but fewer (35%) appeared to benefit from the combination. Patients with chronic blepharitis of other aetiologies did not respond to fusidic acid gel but 25% did benefit from oxytetracycline and 30% from the combination. Our results demonstrate the need to investigate patients with blepharitis for concomitant rosacea as they respond well to targeted therapy.

Evaluation of 0.75% metronidazole gel in acne--a double-blind study

Metronidazole, an imidazole, is an antibiotic with established efficacy against anaerobic bacteria. To date, however, there are no published data concerning the efficacy of topical metronidazole in the treatment of acne. This randomized, double-blind prospective clinical study of 96 patients was performed to investigate the efficacy and tolerability of 0.75% metronidazole gel vs. placebo in the treatment of mild to moderate acne. The results of this study showed no significant benefit in using 0.75% metronidazole gel over placebo in reducing counts of inflamed and non-inflamed lesions of acne. There was also no statistically significant difference between the two groups at any stage in the trial when skin tolerability was assessed.

Development of an orphan drug by a start-up company. MetroGel for rosacea

The Orphan Drug Act of 1983, along with the discovery of a new use for a known drug and an investor willing to assume the necessary risk, brought about the formation of a start-up pharmaceutical company. The primary incentive of the Orphan Drug Act of seven years of marketing exclusivity provided the protection from competition necessary for recovery of the significant research and development and marketing costs. The orphan product, MetroGel, for the treatment of rosacea, required approximately five years of development before it was approved for marketing by the Food and Drug Administration. MetroGel has become the number one drug in the United States for the treatment of rosacea. It currently is marketed in other countries through a licensing agreement with a major pharmaceutical company.

Topical metronidazole gel. Use in acne vulgaris

Two percent metronidazole and 5% benzoyl peroxide cream was evaluated in four clinical trials. It could be shown that this test cream was significantly better than 5% benzoyl peroxide jelly alone, and significantly better than a placebo cream. It was also shown that 2% metronidazole and 5% benzoyl peroxide cream was equal to systemic oxytetracycline therapy. The advisability of the combination of metronidazole and benzoyl peroxide was simultaneously discussed.