Chancroid, known in Thai as rok phlae rim on, is another sexually transmitted infection (STI) that can affect both men and women. It is caused by a bacterium called Haemophilus ducreyi. In anyone who gets it, the infection affects the tissue around the genitals and makes the skin break down into sores. The symptoms look a little different from one sex to another, but they cause a similar amount of discomfort. This may be an unfamiliar disease, or one that seems not especially dangerous, but leaving it untreated is certainly not good for your health, so today we would like to introduce you to it.
Chancroid can be cured with antibiotics prescribed by a doctor, but you should not try to diagnose it or buy medicine to treat it on your own, because a sore in the genital area can be caused by other conditions that look similar, such as syphilis, genital herpes, or other genital ulcer diseases. Getting a proper diagnosis is therefore an important step in choosing the right treatment and reducing the spread of the infection to your sexual partners.
How is chancroid diagnosed?
A doctor will take your sexual history and examine the appearance and location of the sore, as well as check the lymph nodes in your groin. Because chancroid can look similar to syphilis and herpes, the doctor may take a blood test for syphilis, collect a sample from the sore to test for herpes, and consider testing for HIV as well. Culturing Haemophilus ducreyi requires a special culture medium and may not be available at every healthcare facility.
Symptoms of chancroid
Symptoms usually begin to appear within several days of exposure, starting with a small red or raised bump at the spot where the bacteria made contact. The bump may then break open into a painful sore with irregular, fairly soft edges. The base of the sore may be yellow or gray, contains pus, and bleeds easily when touched.
Symptoms that may occur include:
Painful sores on the genitals, around the anus, or wherever the bacteria made contact
Pain or a burning sensation when urine touches the sore during urination
Pain during sex
Swollen, tender lymph nodes in the groin
Lymph nodes that may turn into a pus-filled abscess, known as a bubo
It is important to understand that the chancroid symptoms described above usually result from having sex without the protection of a condom. However, there are other ways the bacteria can enter the body, for example through oral sex or through direct contact with the fluid that drains from a sore. If that fluid touches a break in another person's skin, the bacteria can enter the body right away, and touching the fluid with your hand and then touching your eye can spread it as well. For the most part, chancroid tends to occur in countries that are still very underdeveloped, or where public sanitation is not very clean, such as countries in Africa and Southwest Asia.
Do sexual partners need to be tested and treated too?
Anyone who had sex with the patient in the period before symptoms began should be evaluated by a healthcare professional, even if they have no sores or unusual symptoms, because they may have been infected and could pass it on. The patient should abstain from sexual activity until treatment is complete, the sores have healed, and their partners have been evaluated or treated.
The CDC recommends evaluating and treating any sexual partner who had sex with the patient during the 10 days before symptoms began.
Preventing chancroid
The simple rule is to wear a condom every time you have sex with anyone other than your own partner. And if you are not sure whether your boyfriend, husband, or wife is at risk of infection, it is best to use a condom to be safe. Likewise, if you notice that your partner has a sore in the genital area, you should protect yourself and must never use your mouth or make contact with it.
Another thing worth paying attention to is keeping your own genitals clean, so that you do not develop sores or run the risk of developing them. This gives you confidence every time you have sex. That said, if you find out that you have this disease, it is best to let the person close to you know and to see a doctor for treatment.
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Approaches to treating chancroid
Treatment for this disease can be divided into two methods, depending on its severity or on what the treating doctor considers appropriate. The treatment approaches are:
Taking antibiotics to clear the bacteria from the body, along with medication that helps keep the disease from easily coming back in that person
Surgery, in cases where the infection has spread from an enlarged lymph node into a large, inflamed abscess and the patient has pain in that area. Draining it with a scalpel or a needle helps reduce the lymph node swelling and relieve the pain, although with this method some scarring from the procedure is only natural.
With antibiotic treatment, the sores usually improve within 3 to 7 days, but this also depends on the size of the chancroid sore. Fairly large sores take about 2 weeks to heal. The patient must be very disciplined about taking the medication and should finish the entire course strictly as the doctor advises.
How to take care of yourself when you have chancroid
Some ways to care for yourself so that chancroid heals faster and is less likely to come back include:
Cleaning and washing the genitals often, every day
Not having sex with anyone at all; wait until the sore has healed so that you do not reinfect yourself or spread the infection to others. Having sex also causes pain from friction on the sore and risks spreading the disease to other parts of the body.
Not drinking alcohol of any kind; wait until the sore has healed before drinking
Using a saline solution to clean the sore, then wiping it dry
Is chancroid dangerous?
Chancroid is not as serious as some other sexually transmitted infections, but realistically, no one would want to get it. So whenever you have sex with someone who is not your own partner, you should always protect yourself with a condom. And if you begin to suspect that you have chancroid, it is best to see a doctor to be tested and treated properly. Then you can go on living your life as usual, without any worry.
Because Thailand is a country in the tropics, this disease is detected fairly often. Treating chancroid is not difficult; when patients follow the guidance strictly and appropriately, they may not even be left with a scar. But if it is left untreated, whether in women or men, without proper treatment, there is a chance of developing other, more serious sexually transmitted infections. And for anyone who has HIV in their body, the sores may heal more slowly than they would in a person who is otherwise healthy.
Verified references
Links and relevance to the article’s main topic were reviewed on 13 August 2026. Each source supports only the scope stated in the original document and does not replace personalised medical, legal, or service advice.
