π English
π©Ί Medically reviewed by the Health Decoded Guide Editorial Team · Last reviewed: August 2026
π Quick Summary
Orchitis means inflammation of one or both testicles, most often because of an infection. It can cause testicular pain, tenderness and swelling and may occur together with inflammation of the epididymis.
Sudden or rapidly developing testicular pain should be treated as urgent because testicular torsion can cause similar symptoms and needs immediate treatment.
π¨ Quick Action
Seek urgent/emergency medical help if:
• testicular pain starts suddenly or becomes severe
• pain or swelling develops with nausea or vomiting
• the testicle or scrotum becomes rapidly swollen or very painful
π Do not assume sudden testicular pain is orchitis. Testicular torsion must be ruled out quickly.
1οΈβ£ Introduction
The testicles are part of the male reproductive system and produce sperm and the hormone testosterone.
Orchitis happens when one or both testicles become inflamed. This usually causes pain, tenderness and swelling.
Orchitis can occur on its own, particularly with some viral infections such as mumps.
Bacterial orchitis more commonly occurs when an infection involving the epididymis spreads into the testicle.
When both are affected, it is called epididymo-orchitis.
Orchitis and epididymitis are different conditions, but they commonly occur together.
2οΈβ£ Why does orchitis happen?
An infection causes inflammation inside the testicle.
• viruses or bacteria enter the testicular tissue
• the body's immune system responds with inflammation
• swelling increases blood flow and fluid around the affected area
The inflammation causes pain, swelling and tenderness of the testicle.
3οΈβ£ Common causes
The way the infection reaches the testicle depends on the cause.
Viral orchitis
• commonly caused by mumps virus
• more common after puberty
Bacterial orchitis
Bacterial infection often begins elsewhere in the urinary or reproductive tract and spreads through the epididymis into the testicle.
Possible causes include:
• sexually transmitted infections such as chlamydia or gonorrhoea
• bacteria associated with urinary tract infections
• prostate or urinary tract infections
• urinary problems that make infection more likely
The cause matters because bacterial orchitis may require antibiotics, while viral orchitis is mainly managed by relieving symptoms.
π In younger sexually active men, sexually transmitted infections are an important cause of bacterial orchitis.
4οΈβ£ Symptoms
• pain in one or both testicles
• swelling of the testicle
• redness or warmth of the scrotum
• fever
• nausea or feeling generally unwell
Depending on the underlying infection, some people may also have:
• pain or burning when urinating
• discharge from the penis
• pain during ejaculation
Symptoms usually develop over several hours or days, unlike testicular torsion, which often causes sudden severe pain.
5οΈβ£ Associated symptoms or complications
Most people recover well, especially when treatment begins early.
But complications can occasionally occur.
• epididymitis
• abscess formation
• shrinking of the affected testicle (testicular atrophy)
• reduced fertility in some cases
• chronic testicular pain
Long-term fertility problems are uncommon when only one testicle is affected.
6οΈβ£ π©Ί When it becomes dangerous π¨
• sudden severe testicular pain
• rapidly increasing swelling
• severe fever or chills
• nausea or vomiting with severe testicular pain
• severe redness spreading across the scrotum
π These may indicate:
• testicular torsion, which can cut off the blood supply to the testicle and requires immediate medical assessment.
• severe infection or another medical emergency that require urgent medical assessment
7οΈβ£ Management / treatment
Treatment depends on what is causing the inflammation.
For viral orchitis, treatment mainly focuses on controlling pain and swelling while the infection settles.
Measures that may help include:
• rest
• supporting or elevating the scrotum
• applying a cold pack wrapped in cloth
• appropriate pain relief or anti-inflammatory medicine when safe for you
For bacterial orchitis or epididymo-orchitis, antibiotics may be needed.
The choice of antibiotic depends on the likely infection and any test results.
If a sexually transmitted infection is suspected or confirmed, sexual partners may also need testing or treatment.
Follow professional advice about when it is safe to resume sexual activity.
π Early treatment reduces the risk of long-term complications and improves recovery.
8οΈβ£ Diagnosis
• medical history and physical examination
• urine tests and sexually transmitted infection testing when appropriate
• ultrasound scan of the scrotum
• blood tests in selected cases
π Ultrasound helps distinguish orchitis from other causes of testicular pain, including testicular torsion.
π’ Important Message
Painful or swollen testicles should never be ignored. Orchitis is usually treatable, and most people recover well.
Prompt medical assessment helps identify the cause quickly and ensures the right treatment is started as soon as possible.
FAQ
• Can mumps cause orchitis?
Yes. Mumps is one of the most common viral causes of orchitis, particularly in males after puberty.
• Is orchitis contagious?
Orchitis itself is not contagious, but infections that cause it, such as mumps or some sexually transmitted infections, can spread to others.
• Can orchitis affect fertility?
Most people recover without fertility problems, but severe or bilateral orchitis may reduce fertility in some cases.
• Is orchitis the same as epididymitis?
No. Orchitis affects the testicle, while epididymitis affects the epididymis. However, both conditions often occur together.
• Does orchitis always need antibiotics?
No. Antibiotics are used when a bacterial infection is suspected or confirmed. They do not treat viral orchitis.
π§ Why We Delay
Many men feel embarrassed to discuss pain or swelling in the testicles and may hope the problem will disappear on its own. Others mistake the pain for a minor injury and delay seeking medical care.
Although orchitis is often treatable, sudden testicular pain can also be caused by testicular torsion, a medical emergency that requires immediate treatment to help save the testicle.
π Never ignore sudden pain or swelling in a testicle—getting checked quickly can make a significant difference.
π Related Health Topics
• Mumps
• Epididymitis
• Testicular Torsion
• Sexually Transmitted Infections (STIs)
• Urinary Tract Infection (UTI)
π Medical References
• MedlinePlus. Orchitis.
• Mayo Clinic. Orchitis.
• MSD Manual Consumer Version. Orchitis.
• Cleveland Clinic. Orchitis.
• American Urological Association (AUA). Urologic Health Information.
β οΈ Medical Disclaimer
This article is for educational purposes only and does not replace professional medical advice.