Table of ContentsView AllTable of ContentsCausesRisk FactorsTransmissionSymptomsInfectiousnessDiagnosisTreatmentComplicationsReinfectionPrevention
Table of ContentsView All
View All
Table of Contents
Causes
Risk Factors
Transmission
Symptoms
Infectiousness
Diagnosis
Treatment
Complications
Reinfection
Prevention
By far, the most common cause ischlamydia. Although other bacteria, viruses, fungi, and parasites can also cause urethral inflammation, NGU is transmitted almost exclusively throughvaginal,anal, andoral sex.
NGU is more common in males than females, causing symptoms like itching, pain when urinating, and a discharge from the penis. In females, there may be no symptoms until complications likepelvic inflammatory disease (PID)develop. The treatment of NGU depends on the underlying cause.
This article explains the causes and symptoms of nongonococcal urethritis, including how the condition is diagnosed, treated, and prevented.
supersizer / Getty Images
Gender DefinitionsFor purposes of this article, “male” and “man” refer to a person with a penis, and “female” or “woman” refer to a person with a vagina, regardless of thegender or gendersthey identify with. When research or health authorities are cited, the gender terms reflect those used in the cited source.
Gender Definitions
For purposes of this article, “male” and “man” refer to a person with a penis, and “female” or “woman” refer to a person with a vagina, regardless of thegender or gendersthey identify with. When research or health authorities are cited, the gender terms reflect those used in the cited source.
What Causes Nongonococcal Urethritis?
Other viruses, bacteria, fungi, and parasites are also known to cause NGU, albeit less commonly.Although some of these causes (likeEscherichia coliand yeast infection) are not regarded as STIs, sexual transmission is seen to be the primary route of infection to the urethra.
There are also nonsexual causes of NGU, includingurinary tract infections (UTIs),bacterial prostatitis(infection of the prostate),urethral stricture(narrowing of the urethra),phimosis(a foreskin that cannot retract),urinary catheters, and irritants (likespermicides).
But these are less likely culprits, and some NGU cases are entirelyidiopathic(meaning of unknown origin).
Gonococcal Urethritis vs. Nongonococcal Urethritis
If a person has symptoms of urethritis, aswab will be taken from the urethraand examined under the microscope. If gonorrhea is ruled out, NGU is diagnosed.
With that said, it is not uncommon for a person to have gonorrhea, chlamydia, and evenM. genitaliumall at the same time.
Cause of an Itchy Urethra in Men
Who Gets NGU?
NGU is more common in males, but people of any sex can acquire it.
Males are vulnerable to NGU due to the makeup of their urethra. Compared to the female urethra, which is rich in mucus and microorganisms that shield it from infection, the male urethra has less mucus and relatively few protective microorganisms.
Vaginal sex also appears to change the composition of microorganisms in the male urethra, making cells and tissues more vulnerable to STIs like chlamydia.
Meanwhile, anal sex exposes the male urethra to enteric (intestinal) bacteria likeE. colifound in feces. There are few ways to get anE. coliinfection in the urethra other than through sex.
While females can get NGU from an STI like chlamydia, the majority of cases will beasymptomatic, meaning without symptoms. If there are symptoms, they are more likely to involve thecervix, rectum, or throat.
By comparison, males with NGU are 3 times more likely to have symptoms than not.Symptoms typically involve the urethra, rectum, or throat.
Causes of Urethral Pain and When to Seek Care
How Does NGU Spread?
The infectious agents that cause NGU can be transmitted (passed) through vaginal (penis-to-vagina) and anal (penis-to-rectum) sex. Several infections are also readily spread through oral (penis-to-throat) sex, includingM. genitalium,herpes simplex virus types 1 and 2, andHaemophilusstrains.
Factors that increase the odds of transmission include:
Which STIs Cause Itching?
NGU Symptoms
The symptoms of nongonococcal urethritis can vary based not only on the type of infection you have but also on whether you have a penis or vagina.
Common symptoms of NGU include:
Males might also experience inflammation of the penis head (balanitis), foreskin (posthitis), and opening of the penis (meatitis).
Females often experience the need tourinate urgently or frequently.There may also have vaginal pain, discharge, and bleeding due tocervicitis(inflammation of the cervix), a condition that often accompanies NGU in females.
Can You Tell NGU From Gonorrhea?With NGU, the urethral discharge will usually be thin, clear or creamy, and relatively sparse. By contrast, the urethral discharge from gonorrhea is usually copious, thick, and pus-like.
Can You Tell NGU From Gonorrhea?
With NGU, the urethral discharge will usually be thin, clear or creamy, and relatively sparse. By contrast, the urethral discharge from gonorrhea is usually copious, thick, and pus-like.
How Long Can You Spread NGU?
The STIs that cause NGU can be transmitted from the time the infection occurs until the infection is treated and cured.This poses significant health concerns as many people with chlamydia andM. genitaliumare asymptomatic and may unwittingly transmit it to others without even realizing it.
Untreated chlamydia may spontaneously clear without treatment in roughly 1 in 5 people,but there is no way to predict in whom the infection might persist or clear.M. genitaliumcan also clear, usually within one year, but only testing can tell when you are no longer likely to transmit it.
Because of this, you should never wait for chlamydia orM. genitaliumto go away on its own. Left untreated, they can cause serious harm to your health and the health of others.
Risk Factors for STIs You Should Know
Testing for NGU
An NGU diagnosis is made when a person with urethritis is tested and gonorrhea is ruled out as a cause.
The diagnosis starts with a review of your symptoms and medical history. This may include questions about your sex life and sex partners. A physical exam is then performed to examine your urethra.
To confirm whether gonorrhea or some other agent is involved, your healthcare provider will take a swab of urethral discharge to examine under the microscope. The sample is then smeared onto a glass slide and dyed with aGram stain.
The Gram stain can determine if there are any gram-negative bacteria in the sample and if they have the telltale features ofNeisseria gonorrhoeae(namely, a round shape connected in pairs like a peanut). If they do not, NGU is diagnosed.
How Accurate Is Gram Staining?A 2018 study in theFirst International Journal of Andrologyreported that Gram staining of urethral smears have a 92.9% sensitivity in correctly detecting gonorrhea.
How Accurate Is Gram Staining?
A 2018 study in theFirst International Journal of Andrologyreported that Gram staining of urethral smears have a 92.9% sensitivity in correctly detecting gonorrhea.
Other tests may be ordered to investigate other possible causes.
NGU Treatment
As the predominant causes of NGU, chlamydiaandM. genitaliumare both treated with oralantibioticsto clear the infection.
While the choice of antibiotic will ideally be matched to the type and strain of bacteria you have, this is not always possible. In such cases, the Centers for Disease Control and Prevention (CDC) recommends that the following antibiotics be prescribed presumptively (based on the probability of an infection):
The antibiotics can treat both infections, but doxycycline generally has greater activity againstChlamydia trachomatis,while Zithromax tends to have greater activity againstM. genitalium.
Antibiotics may also be prescribed presumptively if the cause is unknown. Other medications still may be prescribed if a viral, fungal, or parasitic cause is diagnosed.
How NGU Is Treated
What Happens If I Don’t Get Treated?
Leaving any STI untreated places sexual partners at risk of infection. But it also places your own health at risk.
Untreated, chlamydia can lead to potentially serious complications in people of any sex, including:
What Are the Risks of Untreated STIs?
If I Have Had an NGU Infection, Am I Immune?
Getting treated and cured of an STI doesn’t mean you can’t get it again. In fact, studies suggest that 1 in 7 females aged 14 to 34 in the United States will get reinfected with chlamydia within four months of being successfully treated.
One problem with reinfection is that repeated exposure to antibiotics increases the risk of antibiotic resistance, causing the drugs to become less and less effective.
In recent years, increasing rates of resistance have been seen with Zithromax, a drug used to treat a host of infections.Because of this, the CDC recommends multiple-day treatment with Zithromax—rather than a single dose—for certain people, including those with a history of STIs.
With most STIs, exposuredoes notmake you immune to the infections. So you can get them again and again unless you take steps to change behaviors and reduce your risk of exposure.
Which STIs are Curable?
How to Prevent the Spread of NGU
With NGU, the main route of infection is sexual, so it’s important to practice safer sex and improve sexual hygiene to reduce your risk of infection.
You can do so in the following ways:
Chlamydia Screening RecommendationBecause chlamydia in women is often asymptomatic, the CDC recommends annual screening for all sexually active women under 25 years and for women 25 years or older who are at increased risk of infection. Annual chlamydia screening is also advised for all sexually activemen who have sex with men.
Chlamydia Screening Recommendation
Because chlamydia in women is often asymptomatic, the CDC recommends annual screening for all sexually active women under 25 years and for women 25 years or older who are at increased risk of infection. Annual chlamydia screening is also advised for all sexually activemen who have sex with men.
A Guide to Regular STI Screenings
Summary
Males get NGU more often than females due to anatomical differences in the urethra of males vs. females. Symptoms include pain with urination, itching, and a clear or creamy discharge. If left untreated, NGU can lead to pelvic inflammatory disease, chronic prostatitis, reactive arthritis, and pregnancy complications.
I Had Unprotected Sex. What Should I Do?
19 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
American Sexual Health Association.How is NGU transmitted?
Moi H, Blee K, Horner PJ.Management of non-gonococcal urethritis.BMC Infect Dis.2015;15:294. doi:10.1186/s12879-015-1043-4
Workowski KA, Bachmann LH, Chan PA, et al.Sexually transmitted infections treatment guidelines, 2021.MMWR Recomm Rep.2021;70(4):1–187. doi:10.15585/mmwr.rr7004a1
New York State Department of Health.Nongonococcal urethritis (NSU, NGU).
Toh E, Xing Y, Gao X, et al.Sexual behavior shapes male genitourinary microbiome composition.Cell Rep Med.2023;4(3):100981. doi:10.1016/j.xcrm.2023.100981
Rowlinson E, Hughes JP, Chambers LC, et al.Incidence of non-gonococcal urethritis (NGU) in men who have sex with women (MSW) and associated risk factors.Sex Transm Dis.2021;48(5):341–6. doi:10.1097/OLQ.0000000000001314
Centers for Disease Control and Prevention.About chlamydia.
Rowlinson E, Chambers L, Lowens S, et al.Risk factors for incident non-gonococcal urethritis (NGU) in men who have sex with women (MSW) attending an STD clinic.Sex Trans Infect.2019;95(Suppl 1). doi:10.1136/sextrans-2019-sti.847
Alberta Department of Health (Canada).Non-gonococcal urethritis (NGU).
Fairhead CEL, Hampson A, Dwyer-Hemmings L, Vasdev N.Is non-chlamydial non-gonococcal urethritis associated with significant clinical complications in men? A systematic review.Curr Urol.2020 Mar;14(1):1–13. doi:10.1159/000499266
Xie J, Li X, Lu Y, et al.Female chronic posterior urethritis is underestimated in patients with lower urinary tract symptoms.Transl Androl Urol.2021 Aug;10(8):3456-64. doi:10.21037/tau-21-550
Geisler WM, Lensing SY, Press CG, Hook EW.Spontaneous resolution of genital Chlamydia trachomatis infection in women and protection from reinfection.J Infect Dis.2013;207(12):1850–1856. doi:10.1093/infdis/jit094
Vandepitte J, Weiss HA, Kyakuwa N, et al.Natural history ofMycoplasma genitaliuminfection in a cohort of female sex workers in Kampala, Uganda.Sex Transm Dis. 2013;40(5):42-7. doi:10.1097/OLQ.0b013e31828bfccf
Sarier M, Sepin N, Duman I, et al.Microscopy of Gram-stained urethral smear in the diagnosis of urethritis: which threshold value should be selected?Andrologia.2018;50(10):e13143. doi:10.1111/and.13143
National Health Service (UK).Complications - chlamydia.
Bielecki R, Ostaszewska-Puchalska, Zdrodowsk-Stefanow, Baltaziak M, Skawronska M, Sokolowska M.The presence of Chlamydia trachomatis infection in men with chronic prostatitis,Cent European J Urol.2020;73(3):362–8. doi:10.5173/ceju.2020.0040
Cha S, Newman DR, Rahman M, Peterman TA.High rates of repeat chlamydial infections among young women — Louisiana, 2000–2015.Sex Transm Dis.2019 Jan;46(1):52–7. doi:10.1097/OLQ.0000000000000906
Centers for Disease Control and Prevention.Getting tested for STIs.
Meet Our Medical Expert Board
Share Feedback
Was this page helpful?Thanks for your feedback!What is your feedback?OtherHelpfulReport an ErrorSubmit
Was this page helpful?
Thanks for your feedback!
What is your feedback?OtherHelpfulReport an ErrorSubmit
What is your feedback?
By clicking “Accept All Cookies”, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts.Cookies SettingsAccept All Cookies
By clicking “Accept All Cookies”, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts.
Cookies SettingsAccept All Cookies
