Inhibitory Activity of Antibacterial Mouthwashes and Antiseptic Substances against Neisseria gonorrhoeae.

Improved treatment and prevention strategies, such as antimicrobial mouthwashes, may be important for addressing the public health threat of antimicrobial-resistant Neisseria gonorrhoeae. Here, we describe the activity of seven common antibacterial mouthwashes and antiseptics against N. gonorrhoeae isolates, incorporating the use of a human saliva test matrix. Our data demonstrate that antibacterial mouthwashes and antiseptics vary in their ability to inhibit the in vitro growth of N. gonorrhoeae and saliva may impact this inhibitory activity.

Incidence and duration of incident oropharyngeal gonorrhoea and chlamydia infections among men who have sex with men: prospective cohort study.

OBJECTIVES: This prospective cohort study aimed to determine the natural history and incidence of oropharyngeal gonorrhoea and chlamydia among a cohort of men who have sex with men (MSM) over a 12-week period, and to examine risk factors associated with incident oropharyngeal infections. METHODS: MSM either aged ≥18 years and had a diagnosis of oropharyngeal gonorrhoea by nucleic acid amplification test (NAAT) in the past 3 months or aged 18-35 years who were HIV-negative taking pre-exposure prophylaxis (PrEP) were eligible for this study. Enrolled men were followed up for 12 weeks. Oropharyngeal swabs were collected at week 0 (baseline) and week 12 (end of study). Between these time points, weekly saliva specimens and the number of tongue kissing, penile-oral and insertive rimming partners were collected by post. Oropharyngeal swabs and saliva specimens were tested by NAAT for Neisseria gonorrhoeae and Chlamydia trachomatis. Poisson regression was performed to examine the risk factors (weekly number of partners) associated with incident oropharyngeal gonorrhoea. RESULTS: A total of 100 MSM were recruited. The incidence of oropharyngeal gonorrhoea and chlamydia was 62 (95% CI 37 to 105) and 9 (95% CI 2 to 35)/100 person-years, respectively. The median duration of incident oropharyngeal infection with gonorrhoea was 28 days (IQR=21-36, n=7). The incidence rate ratio (IRR) for oropharyngeal gonorrhoea increased with an increased number of kissing partners (IRR=1.08; 95% CI 1.03 to 1.12) an increased number of penile-oral sex partners (IRR=1.07, 95% CI 1.01 to 1.14) but not with an increased number of insertive rimming partners (IRR=1.11, 95% CI 0.96 to 1.29) or other demographic factors. The IRR and duration of incident oropharyngeal chlamydia were not calculated due to the small number of cases (n=2). CONCLUSIONS: MSM have a high incidence of oropharyngeal gonorrhoea and the median duration of infection was less than 3 months.

Sites in the oropharynx reached by different methods of using mouthwash: clinical implication for oropharyngeal gonorrhoea prevention.

OBJECTIVES: Oropharyngeal gonorrhoea is increasing among men who have sex with men and is commonly found in the tonsils and at the posterior pharyngeal wall. To address this rise, investigators are currently trialling mouthwash to prevent oropharyngeal gonorrhoea. We aimed to determine which parts of the oropharynx were reached by different methods of mouthwash use (oral rinse, oral gargle and oral spray). METHODS: Twenty staff at Melbourne Sexual Health Centre participated in the study from March to May 2018. Participants were asked to use mouthwash mixed with food dye, by three application methods on three separate days: oral rinse (15 s and 60 s), oral gargle (15 s and 60 s) and oral spray (10 and 20 times). Photographs were taken after using each method. Three authors assessed the photographs of seven anatomical areas (tongue base, soft palate, uvula, anterior tonsillar pillar, posterior tonsillar pillar, tonsil, posterior pharyngeal wall) independently and scored the dye coverage from 0% to 100%. Scores were then averaged. RESULTS: The mean coverage at the sites ranged from 2 to 100. At the posterior pharyngeal wall, spraying 10 times had the highest mean coverage (29%) and was higher than a 15 s rinse (2%, p=0.001) or a 15 s gargle (8%, p=0.016). At the tonsils, there was no difference in mean coverage between spray and gargle at any dosage, but spraying 20 times had a higher mean coverage than a 15 s rinse (42% vs 12%, p=0.012). CONCLUSION: Overall, spray is more effective at reaching the tonsils and posterior pharyngeal wall compared with rinse and gargle. If mouthwash is effective in preventing oropharyngeal gonorrhoea, application methods that have greater coverage may be more efficacious.

Sexual practices of female sex workers in Melbourne, Australia: an anonymous cross-sectional questionnaire study in 2017-18.

Background Sexually transmissible infections (STIs) are rising among female sex workers (FSW) in Australia. The rise might be explained by changes in sexual practices; however, there is limited behavioural data available. This study aimed to explore the current sexual practices among FSW in Melbourne. METHODS: This cross-sectional study was conducted among FSW at Melbourne Sexual Health Centre between September 2017 and March 2018. Participants were asked about current sexual practices with male clients in an average working week. The frequency and proportion of each sexual practice was calculated. RESULTS: There were 180 questionnaires included in the analysis. The median age of the FSW was 28 years (interquartile range [IQR]: 25-34). Most FSW (80.6%) worked in brothels. In an average working week, FSW had a median of 10 (IQR: 7-20) male clients. The most common sexual practices included: vaginal sex (98.3%), fellatio (97.2%), cunnilingus (92.2%) and tongue-kissing (83.7%). FSW had a median number of 10 (IQR: 6-18) vaginal, 10 (IQR: 5-18) fellatio, 7 (IQR: 2-10) cunnilingus and 6 (IQR: 2-10) tongue-kissing clients. Consistent condom use with all clients was highest for vaginal sex (97.1%), followed by anal sex (92.3%), then fellatio (78.9%). Only 3.1% used dental dams consistently for cunnilingus. CONCLUSION: Consistent condom use with all clients was high among FSWs, especially for vaginal and anal sex. However, one-fifth of FSW had condomless fellatio during an average working week. Tongue-kissing was more common than previously published. Peer-led sexual health education on safe sex practice for FSW is of high importance.

Bacterial Load of Chlamydia trachomatis in the Posterior Oropharynx, Tonsillar Fossae, and Saliva among Men Who Have Sex with Men with Untreated Oropharyngeal Chlamydia.

The aim of this study was to determine whether Chlamydia trachomatis could be detected in saliva and if infection is specific to an anatomical site in the oropharynx. Men who have sex with men (MSM) who were diagnosed with oropharyngeal chlamydia at the Melbourne Sexual Health Centre in 2017-2018 were invited to participate upon returning for treatment. Swabs at the tonsillar fossae and posterior oropharynx and a saliva sample were collected. Throat samples were tested for C. trachomatis by the Aptima Combo 2 assay. The bacterial loads of C. trachomatis in all samples were assessed by quantitative PCR (qPCR) detecting the ompA gene. We calculated the positivity and bacterial load of C. trachomatis for all samples. Forty-two MSM were included. The median age was 28 years (interquartile range [IQR], 24 to 33 years). Thirty-two participants (76.2%; 95% confidence interval [CI], 60.5% to 87.9%) had C. trachomatis detected by qPCR at both the tonsillar fossae and the posterior oropharynx, followed by 9.5% (n = 4; 95% CI, 2.7% to 22.6%) positive at the posterior oropharynx only and 4.8% (n = 2; 95% CI, 0.58% to 16.2%) positive at the tonsillar fossae only. Twenty-nine MSM had C. trachomatis detected in saliva (69.0%; 95% CI, 52.9% to 82.3%). The median C. trachomatis load in saliva was 446 copies/ml (IQR, 204 to 1,390 copies/ml), that in the tonsillar fossae was 893 copies/swab (IQR, 390 to 13,224 copies/ml), and that in the posterior oropharynx was 1,204 copies/swab (IQR, 330 to 16,211). There was no significant difference in C. trachomatis load between the tonsillar fossae and the posterior oropharynx (P = 0.119). Among MSM with oropharyngeal chlamydia, nearly three-quarters had chlamydia DNA detected in saliva, although the viability and implications for transmission are unknown.

Translating mouthwash use for gonorrhoea prevention into a public health campaign: identifying current knowledge and research gaps.

The gonorrhoea rate among gay and bisexual men who have sex with men (MSM) has been increasing rapidly in many Western countries. Furthermore, gonorrhoea is becoming increasingly resistant to antibiotics and only limited options remain for treatment. Recent evidence suggests that the oropharynx may play an important role in gonorrhoea transmission. It is hypothesised that reducing the prevalence of oropharyngeal gonorrhoea will also reduce the population incidence of gonorrhoea. Mouthwash has been proposed as a novel non-antibiotic intervention to prevent oropharyngeal gonorrhoea; hence, reducing the probability of antibiotic resistance developing. However, its efficacy is yet to be confirmed by a randomised controlled trial - the findings of which will be available in 2019. If the trial shows mouthwash is effective in preventing gonorrhoea, this finding could potentially be translated into a public health campaign to increase the mouthwash use in the MSM population. This article summarises the current evidence of the effectiveness of mouthwash against gonorrhoea and discusses the potential literature gaps before implementing the mouthwash intervention at a population level.

A multicentre double-blind randomised controlled trial evaluating the efficacy of daily use of antibacterial mouthwash against oropharyngeal gonorrhoea among men who have sex with men: the OMEGA (Oral Mouthwash use to Eradicate GonorrhoeA) study protocol.

BACKGROUND: Gonorrhoea is one of the most common sexually transmissible infections in men who have sex with men (MSM). Gonorrhoea rates have increased substantially in recent years. There is concern that increasing gonorrhoea prevalence will increase the likelihood of worsening antibiotic resistance in Neisseria gonorrhoeae. A recent randomised controlled trial (RCT) demonstrated that a single-dose of mouthwash has an inhibitory effect against oropharyngeal gonorrhoea. We are conducting the first RCT to evaluate whether daily use of mouthwash could reduce the risk of acquiring oropharyngeal gonorrhoea. METHODS/DESIGN: The OMEGA (Oral Mouthwash use to Eradicate GonorrhoeA) study is a double-blind RCT and will be conducted at several sexual health clinics and high caseload General Practice (GP) clinics in Melbourne and Sydney, Australia. A total of 504 MSM attending the participating sites will be recruited. Participants will be randomised to either using 'Study mouthwash A' or 'Study mouthwash B' for 12 weeks. Study mouthwash A was inhibitory against N. gonorrhoeae in vitro, whereas study mouthwash B was not. Participants will be instructed to rinse and gargle the study mouthwash for 60 seconds every day. The primary outcome is the proportion of participants with oropharyngeal gonorrhoea detected by nucleic acid amplification test by 12 weeks. DISCUSSION: The results from this trial may provide a novel way to reduce gonorrhoea prevalence and transmission without the use of antibiotics that may be associated with development of resistance. If shown to be effective, the widespread use of mouthwash will reduce the prevalence of oropharyngeal gonorrhoea, which plays key role in driving the emergence of gonococcal antimicrobial resistance through DNA exchange with oral commensal bacteria. The anticipated net effect will be interruption of onward transmission of N. gonorrhoeae within high density sexual networks within MSM populations. TRIAL REGISTRATION: Australian New Zealand Clinical Trials Registry ACTRN12616000247471 , registered on 23rd February 2016.

Understanding Risk Factors for Oropharyngeal Gonorrhea Among Sex Workers Attending Sexual Health Clinics in 2 Australian Cities: Mixed Methods Study.

BACKGROUND: The risk factors for oropharyngeal gonorrhea have not been examined in sex workers despite the increasing prevalence of gonorrhea infection. OBJECTIVE: This study aims to determine the risk factors for oropharyngeal gonorrhea in female and gender-diverse sex workers (including cisgender and transgender women, nonbinary and gender fluid sex workers, and those with a different identity) and examine kissing, oral sex, and mouthwash practices with clients. METHODS: This mixed methods case-control study was conducted from 2018 to 2020 at 2 sexual health clinics in Melbourne, Victoria, and Sydney, New South Wales, Australia. We recruited 83 sex workers diagnosed with oropharyngeal gonorrhea (cases) and 581 sex workers without (controls). Semistructured interviews with 19 sex workers from Melbourne were conducted. RESULTS: In the case-control study, the median age of 664 sex workers was 30 (IQR 25-36) years. Almost 30% of sex workers (192/664, 28.9%) reported performing condomless fellatio on clients. Performing condomless fellatio with clients was the only behavior associated with oropharyngeal gonorrhea (adjusted odds ratio 3.6, 95% CI 1.7-7.6; P=.001). Most participants (521/664, 78.5%) used mouthwash frequently. In the qualitative study, almost all sex workers reported kissing clients due to demand and generally reported following clients' lead with regard to kissing style and duration. However, they used condoms for fellatio because they considered it a risky practice for contracting sexually transmitted infections, unlike cunnilingus without a dental dam. CONCLUSIONS: Our study shows that condomless fellatio is a risk factor for oropharyngeal gonorrhea among sex workers despite most sex workers using condoms with their clients for fellatio. Novel interventions, particularly targeting the oropharynx, will be required for oropharyngeal gonorrhea prevention.

Australian Sexual Health Service Users' Perspectives on Reducing the Oral Transmission of Bacterial STIs: A Qualitative Study.

Growing rates of bacterial sexually transmitted infections (STIs) demand new approaches to STI prevention. Sexual practices involving saliva or direct contact with the mouth increase the risk of STI transmission, but community awareness remains largely unexplored in the literature. The Community Awareness and Surveillance of STI Transmission study sought to explore sexual health clinic attendees' awareness of oral STIs; experiences when seeking testing and treatment; and acceptable educational and clinical interventions. Twenty-one semi-structured interviews were conducted with a diverse group of Melbourne Sexual Health Center attendees'. Reflective thematic analysis was undertaken, revealing key themes across people of different genders, sexual identities, ages, and nationalities. All participants emphasized the importance of understanding how their sexual practices might put them at risk of an oral STI. They also sought care from specialist sexual health services with the expectation that health-care providers (HCPs) in these settings had more understanding of diverse sexual practices. Participants' decisions to protect themselves against oral STIs were primarily driven by the effect the decision had on pleasure and intimacy. Comfort during the health-care encounter and trust in HCPs facilitated better understanding of individual STI risk. Differences in awareness and risk reduction strategies were noted based on past experience with oral testing and STIs. These findings highlight the importance of HCPs and public health interventions providing solutions that recognize the central role of pleasure and intimacy in our sexual lives.

The Impact of Mouthwash on the Oropharyngeal Microbiota of Men Who Have Sex with Men: a Substudy of the OMEGA Trial.

Mouthwash is a commonly used product and has been proposed as an alternative intervention to prevent gonorrhea transmission. However, the long-term effects of mouthwash on the oral microbiota are largely unknown. We investigated the impact of 12 weeks of daily mouthwash use on the oropharyngeal microbiota in a subset of men who have sex with men who participated in a randomized trial comparing the efficacy of two alcohol-free mouthwashes for the prevention of gonorrhea. We characterized the oropharyngeal microbiota using 16S rRNA gene sequencing of tonsillar fossae samples collected before and after 12 weeks of daily use of Listerine mouthwash or Biotène dry mouth oral rinse. Permutational multivariate analysis of variance (PERMANOVA) was used to assess differences in oropharyngeal microbiota composition following mouthwash use. Differential abundance testing was performed using ALDEx2, with false-discovery rate correction. A total of 306 samples from 153 men were analyzed (Listerine, n = 78 and Biotène, n = 75). There was no difference in the overall structure of the oropharyngeal microbiota following Listerine or Biotène use (PERMANOVA P = 0.413 and P = 0.331, respectively). Although no bacterial taxa were significantly differentially abundant following Listerine use, we observed a small but significant decrease in the abundance of both Streptococcus and Leptotrichia following Biotène use. Overall, our findings suggest that daily use of antiseptic mouthwash has minimal long-term effects on the composition of the oropharyngeal microbiota. IMPORTANCE Given the role of the oral microbiota in human health, it is important to understand if and how external factors influence its composition. Mouthwash use is common in some populations, and the use of antiseptic mouthwash has been proposed as an alternative intervention to prevent gonorrhea transmission. However, the long-term effect of mouthwash use on the oral microbiota composition is largely unknown. We found that daily use of two different commercially available mouthwashes had limited long-term effects on the composition of the oropharyngeal microbiota over a 12-week period. The results from our study and prior studies highlight that different mouthwashes may differentially affect the oral microbiome composition and that further studies are needed to determine if mouthwash use induces short-term changes to the oral microbiota that may have detrimental effects.

Associations between oral sex practices and frequent mouthwash use in heterosexuals: a cross-sectional survey in Melbourne, Australia.

OBJECTIVE: This study aimed to determine the frequency of mouthwash use and its association to oral sex practice in heterosexuals. DESIGN: A cross-sectional study. SETTING: Data obtained from a sexual health clinic in Victoria, Australia, between March 2019 and April 2019. PARTICIPANTS: Heterosexual men and women attending the sexual health clinic answered a survey using computer-assisted self-interview. PRIMARY AND SECONDARY OUTCOME MEASURES: Univariable and multivariable logistic regression were performed to examine the association between frequent mouthwash use (ie, daily or weekly mouthwash use) and oral sex practices (including tongue kissing, fellatio, cunnilingus and insertive rimming). RESULTS: There were 681 heterosexuals included in the analysis: 315 (46.3%) men and 366 (53.7%) women. Of participants, 302 (44.3%) used mouthwash frequently, 173 (25.4%) used mouthwash infrequently and 206 (30.2%) never used mouthwash. There was no significant difference in the proportion of frequent mouthwash users between men and women (46.4% of men vs 42.6% of women; p=0.329). The proportion of frequent mouthwash users increased with increasing age groups (39.3% in ≤24 years, 45.2% in 25-34 years and 52.8% in ≥35 years or older; ptrend=0.039) with those aged ≥35 years having a 1.80 times (95% CI: 1.12 to 2.89) higher odds of being a frequent mouthwash user than those aged ≤24 years. There were no significant associations between frequent mouthwash users had sexually transmitted infection (STI) risk after adjusting for age and country of birth. CONCLUSION: Older heterosexuals are more likely to use mouthwash. Given the high proportion and associations of mouthwash use in heterosexuals, future investigations related to oral STIs in this group should include mouthwash use.

A comparison of cotton-tipped and nylon flocked swabs for culture of Neisseria gonorrhoeae from oropharyngeal samples.

Our aim was to determine if there was a difference in culture positivity for oropharyngeal gonorrhoea when sampling using a nylon-flocked versus cotton-tipped swab. We collected FLOQSwabs and cotton-tipped swabs from individuals aged ≥ 18 years who had untreated oropharyngeal gonorrhoea detected by NAAT between November 2019-June 2020.Of 78 participants, 32 (41.0%) were culture-positive for N. gonorrhoeae from either swab. Of these 32, 29 (90.6%, 95%CI: 75.0%-98.0%) were positive on both swabs, one (3.1%, 95%CI: 0.0%-16.2%) tested positive on FLOQSwab only and two (6.2%, 95%CI: 0.1%-20.8%) tested positive on cotton-tipped swabs only. There was moderate agreement between the swabs in the amount of bacterial growth (Cohen's Kappa (k)=0.745; 95%CI: 0.622-0.868, p<0.001). Our results showed that the proportion of positive results was comparable using the FLOQSwabs versus the cotton-tipped swabs for oropharyngeal gonorrhoea culture.

Antiseptic mouthwash for gonorrhoea prevention (OMEGA): a randomised, double-blind, parallel-group, multicentre trial.

BACKGROUND: To address the increasing incidence of gonorrhoea and antimicrobial resistance, we compared the efficacy of Listerine and Biotène mouthwashes for preventing gonorrhoea among men who have sex with men (MSM). METHODS: The OMEGA trial was a multicentre, parallel-group, double-blind randomised controlled trial among MSM, done at three urban sexual health clinics and one general practice clinic in Australia. Men were eligible if they were diagnosed with oropharyngeal gonorrhoea by nucleic acid amplification test (NAAT) in the previous 30 days or were aged 16-24 years. They were randomly assigned to receive Listerine (intervention) or Biotène (control) via a computer-generated sequence (1:1 ratio, block size of four). Participants, clinicians, data collectors, data analysts, and outcome adjudicators were masked to the interventions after assignment. Participants were instructed to rinse and gargle with 20 mL of mouthwash for 60 s at least once daily for 12 weeks. Oropharyngeal swabs were collected by research nurses every 6 weeks, and participants provided saliva samples every 3 weeks, to be tested for Neisseria gonorrhoeae with NAAT and quantitative PCR. The primary outcome was proportion of MSM diagnosed with oropharyngeal N gonorrhoeae infection at any point over the 12-week period, defined as a positive result for either oropharyngeal swabs or saliva samples by NAAT, and the cumulative incidence of oropharyngeal gonorrhoea at the week 12 visit. A modified intention-to-treat analysis for the primary outcome was done that included men who provided at least one follow-up specimen over the 12-week study period. The trial was registered on the Australian and New Zealand Clinical Trials Registry (ACTRN12616000247471). FINDINGS: Between March 30, 2016, and Oct 26, 2018, 786 MSM were screened and 256 were excluded. 264 MSM were randomly assigned to the Biotène group and 266 to the Listerine group. The analysis population included 227 (86%) men in the Biotène group and 219 (82%) in the Listerine group. Oropharyngeal gonorrhoea was detected in ten (4%) of 227 of MSM in the Biotène group and in 15 (7%) of 219 in the Listerine group (adjusted risk difference 2·5%, 95% CI -1·8 to 6·8). The cumulative incidence of oropharyngeal gonorrhoea at the week 12 visit did not differ between the two mouthwash groups (adjusted risk difference 3·1%, 95% CI -1·4 to 7·7). INTERPRETATION: Listerine did not reduce the incidence of oropharyngeal gonorrhoea compared with Biotène. However, previous research suggests that mouthwash might reduce the infectivity of oropharyngeal gonorrhoea; therefore, further studies of mouthwash examining its inhibitory effect on N gonorrhoeae are warranted to determine if it has a potential role for the prevention of transmission. FUNDING: Australian National Health and Medical Research Council.

Duration of gargling and rinsing among frequent mouthwash users: a cross-sectional study.

OBJECTIVE: To examine the rinsing and gargling mouthwash practices among frequent mouthwash users to determine if there are differences in use between gender, sexual orientation and sex work status. DESIGN: Cross-sectional study. SETTING: Data obtained from patients attending a sexual health centre located in Melbourne, Australia. PARTICIPANTS: 200 frequent mouthwash users (four or more times per week), 50 for each of the following patient groups: men who have sex with men (MSM), female sex workers (FSW), females who are not sex workers and men who have sex with women only (MSW). Participants were observed and audio recorded using mouthwash. PRIMARY AND SECONDARY OUTCOME MEASURES: Descriptive analyses were conducted to calculate the median age, time rinsing and gargling, amount of mouthwash used and proportion of participants who rinsed, gargled or both, as determined from the audio files. Kruskal-Wallis H test and χ2 test were used to examine differences between the patient groups. RESULTS: Median age was 28 years (IQR: 24-33). During the study, most (n=127; 63.5%) rinsed and gargled, but 70 (35.0%) rinsed only and three (1.5%) gargled only. Median time rinsing was 13.5 s (IQR: 8.5-22.0 s), gargling was 4.0 s (IQR: 2.5-6.0 s) and the median total duration was 17.0 s (IQR: 11.5-25.8 s). Median duration of mouthwash did not differ significantly between the groups (females not sex workers: 18.8 s (IQR: 12.5-24.5 s); FSW: 14.0 s (9.0-22.0 s); MSM: 22.3 s (13.0-26.5 s); MSW: 15.8 s (12.0-25.0 s); p=0.070) but males used mouthwash longer than females (median 20.3 s compared with 15.5 s; p=0.034). The median volume of mouthwash used was 20 mL (IQR: 15-27 mL). And most (n=198; 99.0%) did not dilute mouthwash with water. CONCLUSION: Over a quarter of frequent users do not gargle mouthwash at all (35%) and used it for a substantially shorter period of time than it was used in the randomised trial (1 min) where it was shown to be effective at inhibiting Neisseria gonorrhoeae growth. Our findings suggest that many frequent mouthwash users do not follow the manufacturer instructions for using mouthwash and may not use mouthwash in a way that was shown to reduce the growth of oropharyngeal gonorrhoea.

An open-label, parallel-group, randomised controlled trial of antiseptic mouthwash versus antibiotics for oropharyngeal gonorrhoea treatment (OMEGA2).

New treatments for oropharyngeal gonorrhoea are required to address rising antimicrobial resistance. We aimed to examine the efficacy of a 14-day course of mouthwash twice daily compared to standard treatment (antibiotic) for the treatment of oropharyngeal gonorrhoea. The OMEGA2 trial was a parallel-group and open-labelled randomised controlled trial among men with untreated oropharyngeal gonorrhoea that was conducted between September 2018 and February 2020 at Melbourne Sexual Health Centre in Australia. Men were randomised to the intervention (rinsing, gargling and spraying mouthwash twice daily for 14 days) or control (standard treatment) arm and followed for 28 days. Participants in both arms were advised to abstain from sex and kissing with anyone for 14 days after enrolment. Oropharyngeal swabs were collected at baseline, Day 14 and Day 28 and tested for Neisseria gonorrhoeae by nucleic acid amplification test (NAAT) and culture. The primary outcome was the detection of oropharyngeal N. gonorrhoeae by NAAT at Day 14 after treatment. This trial was registered on the Australian and New Zealand Clinical Trials Registry (ACTRN12618001380280). This trial stopped early due to a high failure rate in the mouthwash arm. Twelve men were randomly assigned to either mouthwash (n = 6) or standard treatment (n = 6). Of the 11 men who returned at Day 14, the cure rate for oropharyngeal gonorrhoea in the mouthwash arm was 20% (95% CI 1-72%; 1/5) and in the standard treatment arm was 100% (95% CI 54-100%; 6/6). A 14-day course of mouthwash failed to cure a high proportion of oropharyngeal gonorrhoea cases.