WEB予約
LINE予約
STD
Male gonorrhea is a sexually transmitted infection caused by Neisseria gonorrhoeae. After an incubation period of 2 to 7 days it typically presents as urethritis with a yellow-white purulent discharge and severe pain on urination. Although symptoms are usually obvious in men, untreated infection can progress to epididymitis, infertility, and disseminated gonococcal infection (gonococcal arthritis). Pharyngeal and rectal infections are usually asymptomatic and act as silent reservoirs of transmission. The first-line treatment is ceftriaxone 1 g by intravenous infusion; oral antibiotics are no longer recommended. In this article, a Men's Care Clinic physician explains the symptoms, incubation period, testing, treatment, and risks of untreated male gonorrhea, based on the STI Diagnosis and Treatment Guidelines of the Japanese Society for Sexually Transmitted Infections.
CONTENTS
Online consultation available: STI testing kits and treatment from home. Discreet shipping, open on weekends and holidays.
LINEBook an STI consultation or test
*If you have symptoms, early consultation directly reduces the risk of complications. *LINE messages are not medical advice. Diagnosis and prescription are decided by a physician at the consultation.

Gonorrhea is a sexually transmitted infection caused by Neisseria gonorrhoeae, a Gram-negative diplococcus that infects mucous membranes. It is also called "gonococcal infection" and is classified as a category V notifiable disease (sentinel surveillance) under Japan's Infectious Diseases Control Law.
N. gonorrhoeae is an extremely fragile organism that can only survive on the surface of mucous membranes. It is highly susceptible to drying, temperature change, and disinfectants, so transmission via toilet seats or shared towels in everyday life is virtually nonexistent. Transmission occurs almost exclusively through direct mucosal contact during sexual activity (vaginal, oral, or anal intercourse).
In men, the primary sites of infection are the urethra, pharynx, and rectum, and symptoms vary considerably depending on the site. Pharyngeal and rectal infections in particular tend to produce few or no symptoms, so the infection can spread unknowingly to others.
Gonorrhea is highly infectious. The probability of male infection from a single act of intercourse with an infected partner is 20-30%, while the probability of female infection is 50-70% (WHO and CDC data). There are only three routes of transmission:
Correct condom use significantly reduces transmission risk, but few people use condoms during oral sex, which is why the pharynx has become an important reservoir for infection. If you develop symptoms after intercourse with a casual partner, you should be tested promptly.
According to the Ministry of Health, Labour and Welfare's National Epidemiological Surveillance of Infectious Diseases, the number of gonococcal infections per sentinel site in Japan has been rising in the 2020s compared with the 2010s. Most cases occur in men in their 20s and 30s, with the following features:
Many infections occur outside sentinel facilities, and the true number of cases is estimated to be 3-10 times the reported figure. Coinfection with chlamydia is found in 20-30% of cases, so chlamydia testing is also recommended when gonorrhea is diagnosed.

Symptoms of male gonorrhea differ markedly by site of infection. In the most common form, gonococcal urethritis, purulent discharge and severe pain on urination are the hallmark symptoms. In contrast, pharyngeal and rectal infections produce few symptoms and are easily missed.
Below we organize the symptoms by site and explain how to spot the infection early.
The classic symptoms of gonococcal urethritis, the most common form in men, are as follows. They appear rapidly 2-7 days after exposure and are typically more severe than in chlamydial urethritis.
These symptoms typically appear suddenly 2-7 days after exposure. Because the discomfort is intense, men are usually motivated to seek care. If symptoms appear, see a doctor immediately. Over-the-counter medicines cannot cure the infection.
Gonococcal urethritis in men can resemble chlamydial urethritis, but there are several differences. Confirmatory diagnosis requires laboratory testing; the table below is provided only as a reference.
| Feature | Gonorrhea | Chlamydia |
|---|---|---|
| Incubation period | 2-7 days (short) | 1-3 weeks (long) |
| Discharge character | Yellow-white to green pus (thick) | Clear to milky (watery to serous) |
| Discharge volume | Large | Small |
| Pain on urination | Severe burning pain | Mild to moderate |
| Onset of symptoms | Abrupt | Gradual |
| Asymptomatic proportion | 10-20% | 30-50% |
| Coinfection | Both pathogens are present simultaneously in 20-30% of cases | |
Symptoms alone are not enough for a definitive diagnosis, so the causative pathogen must be identified by testing before treatment is started. Because the effective antibiotics differ, the wrong choice of treatment will not work.
Gonococcal urethritis in men typically causes prominent symptoms, but 10-20% of infected men have no symptoms or only minimal symptoms. Even without symptoms, they can transmit the infection to others, and the organism continues to spread within their own body. Care is needed.
Pharyngeal and rectal gonorrhea are usually asymptomatic, so testing is recommended for the following situations even in the absence of symptoms:
Do not assume "no symptoms means I'm fine." If you have any concern, getting tested is the most reliable way to break the chain of transmission.

The incubation period for gonorrhea is 2-7 days (average 3-5 days), which is relatively short among sexually transmitted infections. Symptoms appear earlier than with chlamydia (1-3 weeks) or syphilis (about 3 weeks). This reflects the rapid replication of N. gonorrhoeae.
Individual variation exists depending on host immunity and inoculum size, and some cases develop symptoms as late as 14 days after exposure. Even if you suspect a recent exposure but have no symptoms yet, you may still be within the incubation period and should monitor for symptoms.
The clinical course after gonococcal infection can be summarized as follows.
| Time | Changes in the body | Main symptoms |
|---|---|---|
| Immediately after exposure (day 0) | N. gonorrhoeae adheres to and invades the urethral mucosa | None |
| 2-7 days (incubation period) | Bacteria multiply and mucosal inflammation begins | Mild discomfort or itching |
| 3-7 days (onset) | Acute inflammation of the urethra | Purulent discharge and severe pain on urination |
| 2-3 weeks untreated | Bacteria ascend to the prostate and seminal vesicles | Perineal pain, fever, urinary frequency |
| 1-2 months untreated | Bacteria reach the epididymis | Epididymitis (scrotal swelling, pain, fever) |
| Months to years | Hematogenous dissemination throughout the body | Disseminated gonococcal infection (arthritis, skin lesions, fever) |
In men, symptoms are usually severe enough that patients seek care at the onset of disease. However, leaving the infection untreated or using over-the-counter medicines on your own allows the disease to progress to complications. Ideally, see a doctor within 2-3 days of symptom onset.

If male gonorrhea is left untreated, it can cause serious complications such as epididymitis, prostatitis, infertility, and disseminated gonococcal infection. The initial urethral symptoms may resolve on their own, but this is not a cure; it is a sign that the bacteria have spread deeper into the body.
Below we describe the major complications that occur when gonorrhea is left untreated.
Epididymitis is a complication in which N. gonorrhoeae ascends retrograde from the urethra through the vas deferens to inflame the epididymis. It develops in roughly 1-2% of men with untreated gonorrhea.
The most serious sequela is scarring and obstruction of the vas deferens. Bilateral disease can obstruct the passage of sperm, causing obstructive azoospermia, which is a form of male infertility. Once scarring has occurred, it cannot be reversed, so early treatment to prevent progression to epididymitis is critically important.
When N. gonorrhoeae spreads from the urethra to the prostate and seminal vesicles, it can cause acute prostatitis and seminal vesiculitis. Symptoms include:
If the acute phase is left untreated, it can progress to chronic prostatitis and, over months to years, evolve into chronic pelvic pain syndrome (CPPS). Once chronic, treatment becomes difficult, which is why early antibiotic therapy is important.
When N. gonorrhoeae spreads throughout the body via the bloodstream, a serious condition called Disseminated Gonococcal Infection (DGI) can develop. It occurs in 0.5-3% of patients with gonorrhea and is characterized by the following triad:
Rarely, endocarditis or meningitis can complicate DGI, and hospitalization for intravenous therapy is required. DGI can develop without any urethritis symptoms, so diagnosis is often delayed. There are reports of patients who visited an orthopedic clinic with a swollen joint and fever and were eventually found to have gonococcal arthritis.
Mucosal inflammation from gonorrhea has been shown in epidemiologic studies to raise the risk of HIV, syphilis, and hepatitis B by 3-5 fold. This is because disruption of the mucosal barrier makes it easier for viruses to enter.
When gonorrhea is diagnosed, standard practice is to simultaneously test for HIV, syphilis, chlamydia, and hepatitis B and C. At Men's Care Clinic we also recommend a bundled STI panel.
Untreated gonorrhea carries a risk of complications. If you notice any symptoms, please seek care promptly (online consultation; open weekends and holidays).
*Discreet shipping; same-day consultation available. *LINE messages are not medical advice. Diagnosis and prescription are decided by a physician at the consultation.

N. gonorrhoeae can also infect the pharynx (throat) and rectum through oral or anal sex. Infections at these sites typically produce few or no symptoms, making them important reservoirs for ongoing transmission in the community.
For details on pharyngeal gonorrhea see Male pharyngeal gonorrhea: symptoms, testing, and treatment.
Pharyngeal gonorrhea is infection of the oral cavity and throat with N. gonorrhoeae through oral sex such as fellatio. It has the following features:
Pharyngeal gonorrhea cannot be cured with ordinary antibiotic gargles; intravenous ceftriaxone is required. For more details see the article on pharyngeal gonorrhea.
Rectal gonorrhea is infection of the rectal mucosa with N. gonorrhoeae through anal sex or shared sex toys. It is particularly common in men who have sex with men (MSM).
Diagnosis requires a rectal swab for PCR. Urine testing alone cannot detect rectal gonorrhea, so specimens must be collected from each potentially infected site.

The standard test for diagnosing male gonorrhea is nucleic acid amplification testing (NAAT, commonly called PCR). With sensitivity and specificity both above 95%, it can detect even small numbers of organisms, making it the most reliable test available.
The appropriate test depends on when symptoms appeared and which site is affected.
| Site of infection | Specimen | Test method | Time to result |
|---|---|---|---|
| Urethra (male) | First-catch urine (about 5 mL) | PCR (NAAT) | 1-3 days |
| Pharynx | Pharyngeal gargle or swab | PCR (NAAT) | 1-3 days |
| Rectum | Rectal swab | PCR (NAAT) | 1-3 days |
| Suspected disseminated infection | Blood or joint fluid | Culture + PCR | 3-7 days |
An important caveat: for urine testing, the first-catch urine should be collected at least 2 hours after the last void. If urine is sampled immediately after voiding, organisms can be washed away and the result may be falsely negative.
Because coinfection with chlamydia is common, PCR testing for chlamydia is performed at the same time using the same specimen as standard practice when gonorrhea is being investigated.
PCR has become the mainstay in recent years, but with antimicrobial-resistant N. gonorrhoeae on the rise, culture remains important for treatment failures and complex cases.
At Men's Care Clinic we use PCR testing as standard and add culture when indicated.

The first-line treatment for male gonorrhea is a single intravenous dose of ceftriaxone 1 g. It is recommended by every major guideline, including the Japanese Society for Sexually Transmitted Infections, the U.S. CDC, and the WHO. Oral antibiotics are no longer recommended because of resistance concerns.
Treatment is completed in a single infusion, which keeps the number of clinic visits to a minimum.
Ceftriaxone is a third-generation cephalosporin for injection and is one of the few agents that retains nearly 100% efficacy against N. gonorrhoeae.
For patients allergic to ceftriaxone, alternatives such as spectinomycin 2 g intramuscularly may be considered.
In the past, gonorrhea could be treated with oral penicillins, tetracyclines, and fluoroquinolones, but almost all of these are now ineffective due to resistance.
The WHO has designated antimicrobial-resistant N. gonorrhoeae as a "high-priority pathogen", and ceftriaxone-resistant cases have been reported worldwide. For this reason, you must never self-medicate with antibiotics.
Even if symptoms resolve, do not stop treatment on your own. Follow your physician's instructions through to the test of cure.
Untreated gonorrhea carries a risk of complications. If you notice any symptoms, please seek care promptly (online consultation; open weekends and holidays).
*Discreet shipping; same-day consultation available. *LINE messages are not medical advice. Diagnosis and prescription are decided by a physician at the consultation.

Together with chlamydia, gonorrhea is one of the two leading STIs and accounts for the majority of male urethritis cases. Here we put gonorrhea in context by comparing it with other STIs.
For an overview of STIs and other sexually transmitted infections, see Male STIs: a comprehensive guide to types, symptoms, and treatment.
| Disease | Cause | Incubation period | Main symptoms (men) | Treatment |
|---|---|---|---|---|
| Gonorrhea | N. gonorrhoeae (bacterium) | 2-7 days | Purulent discharge, severe dysuria | Ceftriaxone IV |
| Chlamydia | Chlamydia trachomatis (bacterium) | 1-3 weeks | Mild discharge, mild dysuria | Azithromycin or doxycycline |
| Syphilis | Treponema pallidum (bacterium) | About 3 weeks | Initial chancre, roseola | Intramuscular penicillin |
| HIV infection | HIV (virus) | 2-8 weeks (acute phase) | Fever, sore throat, lymphadenopathy | Antiretroviral therapy |
| Genital herpes | HSV (virus) | 2-10 days | Vesicles, ulcers, pain | Valaciclovir, etc. |
| Condyloma acuminatum | HPV (virus) | 3 weeks to 8 months | Wart-like growths | Imiquimod cream, cautery |
The defining features of gonorrhea are its short incubation period and severe symptoms, which often lead to earlier detection than other STIs. However, pharyngeal and rectal gonorrhea cause few symptoms, which is why routine screening is important.
Men's Care Clinic operates three locations: Shimbashi, Akihabara, and Omotesando, and also offers online consultations. Through our medical partnership with Toyosu Hospital, we can also coordinate care smoothly when more specialized treatment is needed. We provide STI testing and treatment for gonorrhea and other infections with full attention to privacy.
All consultations take place in private rooms, and contact with other patients in the waiting area is kept to a minimum.
With online STI care, the workflow is as follows:
There are no initial or follow-up consultation fees. This service is ideal for those who feel uncomfortable visiting a clinic.
Treatment is completed with a single ceftriaxone 1 g infusion. Initial and follow-up consultations are free / Online consultation available
▶ See STI treatment details
▶ Consult online
Below, a Men's Care Clinic physician answers the questions most frequently asked by patients about gonorrhea.
No, it almost never resolves on its own. The initial urethral symptoms may temporarily ease, but this is a sign that the bacteria have moved on from the urethra to the prostate, epididymis, and bloodstream. It is not a cure.
If left untreated, gonorrhea can cause serious complications such as epididymitis, male infertility, and disseminated gonococcal infection. You should always seek proper antibiotic treatment at a medical institution.
No. Over-the-counter products and antibiotics bought online cannot treat gonorrhea. Current strains of N. gonorrhoeae are highly resistant to oral penicillins, tetracyclines, and fluoroquinolones, and the first-line treatment is a single intravenous dose of ceftriaxone 1 g.
Self-medicating with antibiotics can produce drug-resistant strains through inadequate treatment, or temporarily suppress symptoms so that you only seek care once the disease has worsened. Always see a doctor and receive proper treatment.
The treatment itself is completed in a single infusion. A 30-minute intravenous dose of ceftriaxone 1 g eradicates the infection in most patients.
After treatment, however, follow-up proceeds on the following schedule:
For pharyngeal or rectal infection, or when resistance is suspected, the duration of treatment and frequency of repeat testing may be increased.
Both gonorrhea and chlamydia are sexually transmitted urethritis, but the causative organism, incubation period, symptom severity, and treatment all differ.
Coinfection occurs in 20-30% of cases, so if either is positive, the standard approach is to treat for both. For more details, see the article on chlamydia.
If you have symptoms, seek care immediately. If you have no symptoms, testing is best done at least 2-3 days after the at-risk exposure. Immediately after exposure, the organism load may be too low and the test can be falsely negative.
For the most reliable confirmation, waiting about one week is ideal. If you have any concern, testing is recommended early, regardless of symptoms.
Yes. It is essential to inform your partner so that they can also be tested and treated. If you are treated but your partner remains infected, you can re-infect each other in a "ping-pong" pattern.
Ideally, you should contact every partner from the past 2 months, and testing and treatment are recommended even in the absence of symptoms. If you are unsure how to bring it up, your physician can offer advice on how to communicate the news. Please feel free to ask.
There is no protective immunity against gonorrhea, and you can be re-infected any number of times. Re-infection after successful treatment is not unusual. Key points for prevention include:
No vaccine is currently available, so prevention relies on correct condom use and regular testing.
References
STD
関連記事
2026/04/16 STD 【医師監修】クラミジアとは?男性の症状・感染経路・検査・治療を徹底解説
2026/04/04 STD 【医師監修】男性の梅毒とは?症状・感染経路・検査・治療を徹底解説
2022/11/07 STD 梅毒の進行ステージと放置リスク|第1期〜第4期の症状を医師が徹底解説【2026年最新】
2021/09/19 STD 尖圭コンジローマ|男性の症状・治療・HPVワクチンを医師が徹底解説【2026年最新】
2021/09/19 STD B型肝炎の治療と放置リスク|HBs抗原・HBVワクチン・核酸アナログ療法を医師が徹底解説【2026年最新】
2021/09/19 STD C型肝炎の治療と放置リスク|DAA療法でSVR95%超を目指す最新治療を医師が解説【2026年最新】
2021/09/19 STD 男性のトリコモナス|無症状でもうつる?放置リスクと検査・治療法
2021/05/08 STD マイコプラズマ感染症(男性)|症状・検査・治療・耐性菌対策まで医師監修で徹底解説
2021/05/05 STD 男性のヘルペス|性器・口唇の症状・治療・再発予防を医師が徹底解説【2026年最新】
2021/05/02 STD 男性の性器カンジダ症|亀頭炎・包皮炎の症状・治療・予防を医師が徹底解説【2026年最新】
2026.04.16
STD
【医師監修】クラミジアとは?男性の症状・感染経路・検査・治療を徹底解説
2026.04.04
STD
【医師監修】男性の梅毒とは?症状・感染経路・検査・治療を徹底解説
2022.11.07
STD
梅毒の進行ステージと放置リスク|第1期〜第4期の症状を医師が徹底解説【2026年最新】
2021.09.19
STD
尖圭コンジローマ|男性の症状・治療・HPVワクチンを医師が徹底解説【2026年最新】
2021.09.19
STD
B型肝炎の治療と放置リスク|HBs抗原・HBVワクチン・核酸アナログ療法を医師が徹底解説【2026年最新】
2021.09.19
STD
C型肝炎の治療と放置リスク|DAA療法でSVR95%超を目指す最新治療を医師が解説【2026年最新】
2021.09.19
STD
男性のトリコモナス|無症状でもうつる?放置リスクと検査・治療法
2021.05.08
STD
マイコプラズマ感染症(男性)|症状・検査・治療・耐性菌対策まで医師監修で徹底解説
2021.05.05
STD
男性のヘルペス|性器・口唇の症状・治療・再発予防を医師が徹底解説【2026年最新】
2021.05.02
STD
男性の性器カンジダ症|亀頭炎・包皮炎の症状・治療・予防を医師が徹底解説【2026年最新】