Acne (also known as acne vulgaris) remains the most common inflammatory dermatosis treated worldwide, as estimated by global skin disease prevalence studies. Latest reports suggest that the prevalence may be increasing in adolescents and adults, particularly female adults. The concept of 'burden of skin disease' is multidimensional and can be difficult to quantify in light of different healthcare systems across the globe. In acne, the resulting burden may vary according to patient demographics, access to treatments and duration of the disease. The visible nature of acne, symptoms and sequelae all contribute physically and psychosocially to the overall burden of disease, as do the costs required for management. Acne typically presents in adolescence at a time of significant transition. Profound effects on functional status have been demonstrated, along with a strong impact on interpersonal relationships, social functioning and mental health. The high prevalence of acne also presents an economic burden for society. The widespread and prolonged use of antibiotics introduces a potential added burden through resulting antimicrobial resistance. A James Lind Alliance Acne Priority Setting Partnership has identified numerous areas to inform future research, which would help to improve acne management and reduce the burden. The lack of standardized assessments is a major issue in acne trials and challenges the ability to compare treatments and perform meta-analyses. This paper reviews the current literature on burden of acne, identifies areas of treatment uncertainties and summarizes the work of the Acne Core Outcome Research Network as a means of supporting a reduction in the burden of disease.

<h4>Background</h4>Doxycycline is widely used to treat various bacterial infections and has significant global implications, especially as the preferred medication for scrub typhus and leptospirosis. However, its use is limited in children below 8 years of age due to potential adverse effects on teeth and bones. This study aims to assess the risk of dental adverse events associated with doxycycline, a tetracycline-class antibiotic, in children under 8 years of age.<h4>Methods</h4>In this review, we searched PubMed, the Cochrane Library, and Google Scholar for studies published until November 2023. We included studies administering doxycycline to children under 8 years, focusing on dose, duration, and dental adverse events to assess the safety of doxycycline.<h4>Result</h4>A total of 325 articles were initially retrieved, of which 5 studies were available for analysis. This review included information on 162 children who were treated with doxycycline between the ages of 0 and 8 years. The median age at doxycycline administration was 4.25 years and interquartile range (IQR) of 2.065-5.563 years. The oral dosage, based on weight, had a median of 2.3 mg/kg/day, with an IQR of 1.525-5.438 mg/kg/day. The median duration of drug administration was 8.5 days and the IQR of 6-12.5 days. We found a pooled proportion of adverse events of 0.21 (95% CI: 0.13-0.28).<h4>Conclusion</h4>This review suggests that the occurrence of teeth-related adverse events with short-term doxycycline use is minimal, with a low incidence reported. While these findings offer a preliminary basis for the use of doxycycline in children under 8 years of age, the limited number of studies underscore the need for further research to evaluate its therapeutic use and implication for paediatric guidelines.<h4>Systematic review registration</h4>https://www.crd.york.ac.uk/PROSPERO/myprospero, Identifier CRD42023494713. Background Doxycycline is widely used to treat various bacterial infections and has significant global implications, especially as the preferred medication for scrub typhus and leptospirosis. However, its use is limited in children below 8 years of age due to potential adverse effects on teeth and bones. This study pmc-status-qastatus 0 pmc-status-live yes pmc-status-embargo no pmc-status-released yes pmc-prop-open-access yes pmc-prop-olf no pmc-prop-manuscript no pmc-prop-legally-suppressed no pmc-prop-has-pdf yes pmc-prop-has-supplement yes pmc-prop-pdf-only no pmc-prop-suppress-copyright no pmc-prop-is-real-version no pmc-prop-is-scanned-article no pmc-prop-preprint no pmc-prop-in-epmc yes section-at-acceptance Pharmacoepidemiology Introduction Doxycycline is a commonly used antibiotic that belongs to the class of tetracyclines. It was developed in 1967 and has been widely used since then. The dose and duration of doxycycline treatment depend on the specific conditions being treated, as well as the patient’s age, weight, and overall health. Reported side effects of doxycycline include gastrointestinal complaints, photosensitivity, and, in rare cases, allergic reactions. Doxycycline is generally not recommended for children under 8 years, when used for prolonged treatment or repeated courses, due to potential adverse effects on bones and teeth ( Wormser et al., 2019b ). Rauter GmbH and Co., BadS€ackingen, Germany), a handheld spectrophotometer used to evaluate the shade of teeth Tetracycline-like staining was not detected Enamel hypoplasia - 2 (4%) Low Lochary ME et al. In addition, when compared to other tetracyclines, doxycycline exhibits a lower affinity for binding to calcium, with a binding rate of 19% for doxycycline versus 39.5% for tetracycline ( Forti and Benincori, 1969 ). Administering short courses of doxycycline, lasting 10 days or less, to children under 8 years for the treatment of Rocky Mountain Spotted Fever (RMSF) does not cause visible staining (0/68) or increase the risk of enamel hypoplasia (2/68) ( Lochary et al., 1998 ; Todd et al., 2015 ). According to paediatric community-acquired pneumonia (CAP) guidelines, doxycycline is recommended for 10 days for infections caused by atypical organisms such as Mycoplasma pneumoniae, Chlamydia trachomatis , and Chlamydia pneumoniae ( Bradley et al., 2011 ). In this review, one study reported no cases of tooth discoloration (0/31) following doxycycline use for respiratory tract infections, including pneumonia, with a treatment duration of 10 days ( Volovitz et al., 2007 ). These findings add to the growing body of evidence that short-term doxycycline use can be safely prescribed to children without concern for tooth discoloration. Many physicians remain hesitant to prescribe doxycycline in this age group due to concerns about dental side effects—even in life-threatening conditions such as Rocky Mountain Spotted Fever, where doxycycline is the only effective treatment. This review contributes to the growing body of evidence suggesting that short courses of doxycycline may be safe, and highlights the need to reconsider current prescribing practices in critical care settings. The scarcity of large-scale, high-quality studies highlights the need for further research to better understand the long-term impact of doxycycline on dental health and overall safety in children. Future research should focus on large-scale, prospective cohort studies with diverse populations and long-term follow-up to better evaluate the safety profile of doxycycline in pediatric populations. Randomized controlled trials comparing doxycycline with alternative antibiotics are needed to assess relative risks. Special attention should be given to children under the age of 8, with follow-up periods extending to at least 6–12 months post-treatment to adequately monitor for potential adverse effects. Findings from such studies will be critical in guiding evidence-based clinical practice and informing policy decisions regarding the safe use of doxycycline in pediatric populations.

The effect of long term tetracycline treatment for acne vulgaris on the occurrence of R factors in the intestinal flora of man. R factors are known to be the most important mechanism of antimicrobial resistance of intestinal flora. Short courses with therapeutic doses (1000 mg/day) of tetracycline select for strains containing transferable resistance factors to more than one antimicrobial agent. In this report we show that long term treatment with very low doses (100 mg/day) of tetracycline for acne vulgaris has an equally strong effect favouring establishment of resistent strains and R factors in the intestinal flora of patients. Published in The British journal of dermatology (1976)