Before we get into why lymph nodes swell, what it indicates and how to treat the condition, let’s quickly understand a little about lymph nodes in the human body.
- Lymph nodes are small, peanut-sized (usually around 0.5cm) glands that play an important role in defending our body from bacteria, viruses, fungi, and other pathogens.
- The cells in our body dump waste (containing microbes and foreign substances) in the lymphatic fluid.
- The fluid travels to the lymph nodes to undergo a filtration process.
- Lymph nodes filter out the waste stuff in the lymphatic fluid. Lymph nodes contain lymphocytes, a type of white blood cell that kills pathogens.
- When there is a lot of waste to be filtered, more lymphocytes are produced and this results in the swelling of lymph nodes.
Lymph nodes are present in the neck, armpits, groin, stomach, and between the lungs. Lymph nodes are categorised as cervical, axillary, and inguinal lymph nodes depending on their location.

What causes the lymph nodes in the groin to swell?
In short, if the lymph nodes are swollen, understand that your body is fighting an infection but may not be with much success. The infection could be due to an injury, STI, UTI or airborne like Corona. In some cases, even a simple fungal infection like jock itch can cause lymph nodes in the groin to swell.
Common infections such as strep throat, measles, ear infections, infected tooth, viral infections (such as Herpes, HIV, Corona), skin infections can cause swelling of lymph nodes. Immune system disorders such as lupus and rheumatoid arthritis can also cause the swelling. Cancers that originate or spread to the lymph system cause the lymph nodes to swell.
Detecting lymph node swelling by yourself
Know that, in normal circumstances, lymph nodes are very small and movable. Most often, they are not larger than the nail of your little finger. Keeping that in mind, you can look for:
- Pain in your groin, under arms, near neck
- Since they lie just under the skin, you may be able to just see the swelling
- The area may be tender to touch and most often painful
- Moving a swollen lymph node is not as easy and you will find them hard on touching.
Diagnosis
Your doctor will start with a few questions about your current health, medications that you are taking, any recent encounters of unprotected sex or any injury or trauma that you may have met with.
Past that, a complete blood report / picture will be needed to see the levels of various cells in the blood. Increase in white blood cell count, decrease in lymphocytes etc kind of imbalances may signal at a possibly severe infection that your body is trying to fight off. Urine analysis may be required to check for Urinary Tract Infections. A pap test of the cervix, vagina, debris under the foreskin etc if your doctor suspects cancer.
Imaging tests such as CT or MRI may be requested to see the extent of swelling and also to look for the presence of malignant tumours in the body.
Treatment for swollen lymph nodes
The underlying cause is treated because swelling of the lymph nodes is most often caused by the invading pathogens.
- If the infection is bacterial, antibiotics will be given depending on the type of bacteria. In some urgent cases, IV administration of antibiotics may be required.
- For fungal skin infections, antifungal cream or powder may be prescribed.
- For sexually transmitted bacterial infections, appropriate antibiotics (oral medicines) will be given.
- If the infection is caused by virus, antiviral medicines and for HIV, antiretroviral therapy will be the treatment path followed.
- If cancer is detected, treatment can involve chemotherapy, radiation therapy, surgery to remove the tumour(s), immunotherapy etc will be done.
How to prevent the swelling of lymph nodes?
If you keep infections away, chances of getting infections go down and so does the possibility of swollen lymph nodes.
- Wash your hands and legs properly. Wash your hands frequently and surely before eating anything.
- Disinfect your work place and house regularly.
- Always use a condom when having sex, especially if your partner is less known to you.
- If you have pets, keep your pet, house and yourself clean.