Orchitis causes one or both testicles to swell and become painful. Viral infections like the mumps are the most common cause. Other causes include STDs like chlamydia and bacterial infections like UTIs. Orchitis symptoms typically improve over time with at-home care. The condition rarely affects fertility, although the testicles may shrink.
Orchitis (or-KY-tis) is swelling or inflammation of one or both testicles (testes). The testicles are part of the male reproductive system. They make sperm and testosterone (a hormone). Most men have two testicles that sit inside a sac called the scrotum.
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Epididymo-orchitis is having orchitis and a condition called epididymitis at the same time.
Orchitis rarely occurs as the only problem affecting the testicles. When it does, it’s usually related to a mumps infection. A standard childhood vaccine — the Measles, Mumps, Rubella (MMR) — protects against mumps.
Approximately 600,000 boys and men have epididymitis every year. Many of them — almost six in 10 — have epididymo-orchitis.
Orchitis develops because of a viral or bacterial infection. Most cases of orchitis occur because of urinary tract infections, or a sexually transmitted infection (STI), such as chlamydia, gonorrhea or syphilis. Having epididymitis can cause orchitis.
Other viral infections that cause orchitis include:
Other bacterial infections that cause orchitis include:
Anyone who has testicles, at any age, can get orchitis.
Orchitis risk is higher if you have any of these factors:
Orchitis causes mild-to-severe testicle pain and swelling. The condition often begins in one testicle. But it can spread to the other testicle or affect the scrotum.
Other symptoms of orchitis include:
Your healthcare provider will perform a physical exam to check for swollen testicles and tenderness. You may also get these tests:
Orchitis symptoms typically start to ease within a couple of days without treatment. But it can take weeks or months for the swelling to go away completely.
If a bacterial infection or STD causes orchitis, you’ll need treatment. This may involve 10 to 14 days of oral antibiotics. If the infection is an STD, then your partner will need STD treatment, too.
While you’re recovering, avoid having sex or lifting heavy objects. These steps can aid recovery:
You can lower your chances of developing orchitis by getting the mumps vaccine and wearing condoms when having sex. Seeking treatment for BPH or urethral stricture can help prevent orchitis.
Orchitis after puberty that affects both testicles may decrease sperm count. Rarely, orchitis leads to infertility. Orchitis doesn’t affect testosterone production.
Orchitis may also cause:
Most people with orchitis have a full recovery. Infertility and other long-term problems are rare.
You should call your healthcare provider if you experience:
You may want to ask a healthcare provider:
A note from Cleveland Clinic
Orchitis causes swollen testicles and testicle pain. The condition often improves with at-home treatments. Some people need antibiotics to treat an STD or other infection. If an STD led to orchitis, you should notify your partners so they can get treatment, too. Your testicles may be swollen for a few months, although testicle pain should diminish. Your healthcare provider can offer suggestions for easing discomfort.
Last reviewed by a Cleveland Clinic medical professional on 07/08/2021.
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