Chancroid: Symptoms, Pictures, Healing Time and Whether It Goes Away on Its Own
Updated: 1 day ago
Chancroid (also called soft chancre) is a sexually transmitted infection caused by the bacterium Haemophilus ducreyi. It causes a very painful genital sore with soft, non-hardened edges and grey-yellow pus at the base, and it is often accompanied by swollen, tender lymph nodes in the groin. It can be cured with a single-dose antibiotic, taken by mouth or given by injection, but it must first be told apart from syphilis and herpes, which are treated in completely different ways.
Chancroid is now very rare in Thailand compared with 30–40 years ago. Most genital sores that dermatologists see today are herpes and syphilis. This is why buying creams or tablets and guessing that the sore is chancroid so often ends in treating the wrong disease. This article explains what chancroid looks like, how it differs from other sores, which medicines doctors use, at what dose, and how many days it takes to heal.
What causes chancroid, and how is it spread?
Chancroid is caused by Haemophilus ducreyi, a short rod-shaped gram-negative bacterium. The germ enters through tiny breaks in the skin or lining of the genitals during vaginal, anal or oral sex with a person who has a sore.
Incubation period: usually 3–7 days after exposure, and up to 10–14 days in some people.
It is contagious for as long as a sore or pus is present, from the genital sore and from pus when a lymph node bursts.
It is not spread by toilets, swimming pools or sharing meals, because the germ does not survive long outside the body.
Condoms greatly reduce the risk but do not protect completely if the sore lies outside the area the condom covers.
Uncircumcised men are more likely to be infected and to heal more slowly, because the area under the foreskin is moist and easily scraped.
Chancroid matters more than the sore itself, because any open genital sore makes it several times easier to catch and pass on HIV. This is why doctors test for HIV and syphilis in everyone who has a genital sore.
What are the symptoms of chancroid, from day one to an open sore?
Chancroid usually follows a fairly clear sequence.
Days 3–7 after exposure: a small red bump 1–3 millimetres across appears, with a red ring around it.
Within the next 24–48 hours: the bump turns into a pustule and then breaks open into a sore.
Fully developed sore: about 3–20 millimetres across, with ragged edges that are undermined (undermined edge), grey-yellow pus or dead tissue at the base, easy bleeding when touched, and severe pain.
The sore feels soft, not hard when pressed, which is where the name "soft chancre" comes from. A syphilis sore, by contrast, has a firm, button-like edge and base.
There is often more than one sore, and "kissing sores" can appear, meaning two sores facing each other because two skin surfaces touch.
Weeks 1–2: about half of patients develop swollen, tender lymph nodes in the groin, usually on one side.
Patients often say the pain makes walking difficult, underwear rubbing is painful, and urination stings if the sore is near the urethra. Fever is uncommon; a high fever suggests a complicating infection.
What does a chancroid sore look like?
Many people search for pictures of chancroid to compare with their own sore, but many genital diseases look very similar in photos, and even dermatologists do not diagnose from a picture alone. The features to look for, by eye and by touch, are as follows.
Edges: ragged, not a smooth circle, thin and undermined, with a red ring around the margin.
Base: dirty-looking, covered with grey-yellow dead tissue or pus; when wiped away, red flesh that bleeds easily is visible.
Depth: clearly deeper than a herpes sore. Herpes sores are usually shallow erosions.
Sensation: very painful even without touching, unlike an early syphilis sore, which is usually painless.
Number: 1–4 sores or more, and sores may merge into one large ulcer.
If your sore matches some but not all of these points, that does not mean it is not chancroid, and if it matches every point it still needs to be tested to exclude syphilis and herpes, because more than one infection can occur at the same time.
Chancroid in men
What it looks like: a painful sore with soft, ragged edges and pus at the base, most often on the foreskin, the groove below the head of the penis (coronal sulcus), the frenulum and the head of the penis. Some people have sores on the shaft of the penis or around the anus.
Cause: the germ enters through small breaks in the skin during sex. Uncircumcised men are at higher risk.
Severity/urgency: a sore under the foreskin can make the foreskin swell so that it cannot be pulled back (phimosis), or cannot be pulled forward again once retracted (paraphimosis). The latter is an emergency: if the tip of the penis becomes swollen and dark, go to the emergency room immediately.
When to see a doctor: every time you have a genital sore after sex within the past 2 weeks. Do not wait and watch, because the larger the sore, the slower it heals.
Chancroid in women
What it looks like: painful sores on the labia minora, labia majora, vaginal opening, the lower edge of the vaginal opening (fourchette), the perineum or around the anus. Some women have sores on the vaginal wall or cervix that cannot be seen without an examination.
Cause: the same as in men, but a number of women have milder symptoms, so they may not realise they are infected and can pass the infection on.
Severity/urgency: the symptom that brings women to the doctor is often not the sore itself but burning on urination, pain during sex, abnormal vaginal discharge, or pain when passing stool if the sore is around the anus.
When to see a doctor: when you have a sore or burning in the genital area, especially if your partner has a sore or swollen lymph nodes. Always tell the doctor if you are or might be pregnant, because some medicines cannot be used.
Swollen groin lymph nodes that turn into an abscess (bubo)
What it looks like: a painful, swollen, red lump in the groin, usually on one side, appearing about 1–2 weeks after the sore. In about 1 in 4 patients the node turns into an abscess, which feels soft and springy when pressed because it is filled with pus.
Cause: the germ spreads from the sore along the lymph channels to the lymph nodes in the groin.
Severity/urgency: if untreated, the abscess can burst through the skin and become a chronic sore or a draining tunnel (sinus) that heals slowly. For an abscess with a lot of pus, the doctor will drain it with a needle or an incision even after the antibiotic is working. Do not squeeze or puncture it yourself.
When to see a doctor: as soon as you feel a lump in the groin together with a genital sore, or when the lump begins to soften, redden and hurt more.
Chancroid in people with HIV and in pregnant women
What it looks like: people with HIV may have larger, deeper and more numerous sores that heal more slowly than in other people.
Cause: the immune system clears the germ more slowly, and single-dose treatment is more likely to fail.
Severity/urgency: the doctor may choose a multi-day course rather than a single dose, and arrange more frequent follow-up. In pregnant women, ciprofloxacin must not be used; the doctor will choose azithromycin, ceftriaxone or erythromycin instead.
When to see a doctor: as soon as a genital sore appears, and tell the doctor your HIV status or pregnancy at the very first visit.
How does chancroid differ from syphilis, herpes and other sores?
This is the most important part of the article, because each genital disease needs a completely different medicine.
Chancroid: incubation 3–7 days · very painful · soft, ragged, undermined edges · pus at the base · one or several sores · tender groin lymph nodes, usually on one side, may form an abscess
Early syphilis sore (primary syphilis): incubation 10–90 days, average 3 weeks · usually painless · smooth edges, clean base that feels firm like a button · usually a single sore · swollen lymph nodes on both sides, firm, painless, no abscess · read more at Syphilis: symptoms by stage and blood tests
Genital herpes: incubation 2–12 days · usually preceded by burning or itching · starts as small clear blisters in a cluster, then breaks into several shallow sores · can recur in the same place · read more at Genital herpes: what it looks like and how long it takes to heal
Lymphogranuloma venereum (LGV): a very small, painless sore that heals by itself so quickly that it is often unnoticed, then 2–6 weeks later the groin lymph nodes swell into large lumps. It is caused by chlamydia and treated with doxycycline 100 mg twice a day for 21 days.
Sores from Behçet's disease: painful sores like mouth ulcers on the genitals, coming and going, often with mouth ulcers as well. It is not an infection and is not contagious · read more at Behçet's disease
Fixed drug eruption: a dark red patch or erosion on the genitals that appears in the same place every time after taking the same medicine, such as certain painkillers or antibiotics.
Friction sores: usually appear straight after sex, are shallow, have no pus and improve by themselves in 3–5 days.
Remember that a person can have more than one infection at the same time, so a sore that looks like chancroid still needs a blood test for syphilis. If you have bumps or lumps that are not sores, see more about telling them apart at Genital bumps: 10 types and how to tell them apart
How do doctors diagnose chancroid?
Culturing H. ducreyi needs a special growth medium, and even when it is done the germ is found in fewer than 80% of cases. Testing for the germ's genetic material (PCR) is still rarely available. Doctors therefore diagnose chancroid from the symptoms together with ruling out other diseases, and consider it probable when all 4 of the following are met.
One or more painful genital sores
The appearance of the sore and lymph nodes fits chancroid
Tests find no syphilis, both from the sore and from a blood test done at least 7 days after the sore began
A herpes test of the sore is negative
The tests you should have on the first day are a blood test for syphilis (VDRL or RPR together with TPHA), an HIV blood test, a swab of the sore for herpes, and, if there is urethral pus or abnormal vaginal discharge, tests for gonorrhoea and chlamydia. If the first syphilis and HIV results are negative, they should be repeated at 3 months, because early infection may not yet show up.
How is chancroid treated? The medicines doctors actually use
Chancroid is treated with antibiotics taken by mouth or given by injection. Creams alone cannot cure it. There are 4 standard regimens, and the doctor chooses only one according to what suits the patient.
Azithromycin 1 g by mouth as a single dose: the most convenient, suitable for people who worry about forgetting tablets. Common side effects are nausea, diarrhoea and stomach pain; take it after food.
Ceftriaxone 250 mg as a single intramuscular injection: can be used in pregnant women and suits people who vomit or cannot take tablets. Do not use it in people with a severe allergy to cephalosporin antibiotics.
Ciprofloxacin 500 mg by mouth twice a day for 3 days: must not be used in pregnant or breastfeeding women. Do not take it with milk, antacids or calcium, because absorption is reduced.
Erythromycin base 500 mg by mouth three times a day for 7 days: can be used in pregnant women, and some doctors choose it for people with HIV, but it must be taken for several days and can irritate the stomach.
What makes treatment work or fail: finish the full course as prescribed, do not stop on your own when the sore starts to improve, avoid sex until the sore has completely healed, and treat your partner at the same time. If there is no improvement in 7 days, the doctor will review whether the diagnosis is correct, whether there is a co-infection or a resistant germ, and whether the patient has HIV.
The choice of medicine, the dose and the prescription are the doctor's responsibility. The information above is written so that patients understand what treatment to expect, not so that they buy medicine to use on their own.
Creams for chancroid, and wound care while taking the medicine
"Cream for chancroid" is a very common search, but the direct answer is no cream can cure chancroid without an antibiotic taken by mouth or injection, because the germ lies deep in the sore and has already spread to the lymph nodes. Wound care is for reducing pain and preventing re-infection.
Wash the sore twice a day with normal saline (0.9% NaCl) or clean water, and pat it gently dry.
Do not use alcohol or hydrogen peroxide, because they damage the tissue that is repairing itself and hurt a lot.
Do not apply steroid cream, because it suppresses the local immune response, so the sore spreads and heals more slowly.
Antibiotic cream is used only when the doctor sees a complicating infection; it is not the main treatment.
Wear loose cotton underwear and wash your hands every time after touching the sore, so the germ does not reach your eyes or other areas.
Painkillers such as paracetamol can help during the first 2–3 days when the pain is severe.
Can I buy medicine at the pharmacy and take it myself?
We do not recommend it. Although the medicines used for chancroid are common antibiotics, taking them yourself has at least 3 problems.
It may not be chancroid. Most genital sores today are herpes, which antibiotics do not help at all, or syphilis, which needs a different dose of penicillin injection.
Some antibiotics suppress syphilis so the sore shrinks, but the germ is not cleared, and the disease returns weeks later as a body-wide rash. See secondary syphilis rash.
You miss HIV testing and treatment of your partner, which are just as important as treating the sore.
How many days until it heals, and how to follow up
After starting the right medicine, you should improve in this order.
Within 3 days: noticeably less pain.
Within 7 days: the sore becomes visibly smaller and cleaner. This is why the doctor arranges a recheck 3–7 days after starting the medicine.
Small sores heal completely in 1–2 weeks, while large sores may take more than 2 weeks.
A lymph node that has become an abscess shrinks more slowly than the sore, and some people need repeated drainage.
Uncircumcised men and people with HIV heal more slowly.
A healed sore may leave a scar, especially if it was deep or treated late. If there is no improvement at all after 7 days, return to the doctor and do not change medicine on your own.
Does chancroid go away on its own?
Some chancroid sores may eventually heal by themselves, but it takes weeks to months, and during that time the sore can spread deeper and damage genital tissue, the lymph node can become an abscess that bursts into a draining tunnel, or the foreskin can become tight and stuck. Most importantly, for as long as the sore is present the patient can still pass the infection to partners and is more likely to catch HIV, while correct treatment takes only a single dose to 7 days of medicine. Waiting for it to go away is not worth the risk.
What should partners do?
Every partner you had sex with in the 10 days before the sore began should be examined and treated, even if they have no symptoms at all, because a number of women are infected without knowing it.
Avoid every form of sex until both people have finished treatment and the sore has completely healed.
Partners should also have blood tests for syphilis and HIV, for the same reasons as the patient.
How can chancroid be prevented?
Use a condom every time and throughout sex, whether vaginal, anal or oral.
Avoid sex when you or your partner have a sore, bump or pus in the genital area.
Reduce the number of partners, and have regular sexually transmitted infection tests if you have a new partner.
Circumcision reduces the risk in men to some degree.
People at high risk of HIV can talk to a doctor about pre-exposure prophylaxis (PrEP).
When should you see a dermatologist right away?
A sore on the genitals or around the anus within 2 weeks of sex with a new partner
A groin lump that is swollen, painful, red or starting to feel soft as if it contains pus
A sore that is spreading quickly, has black dead tissue, or comes with a high fever
A swollen foreskin that cannot be pulled back, or cannot be pulled forward again once retracted
A sore that has not become smaller after 7 days of medicine
Pregnancy, HIV or diabetes
A dermatologist can examine and treat all sexually transmitted infections that show on the skin. Examinations are private and results are confidential. See other skin conditions at All skin disease articles.
Quick summary
Chancroid is caused by Haemophilus ducreyi and is spread through sex. The incubation period is 3–7 days.
The sore is very painful with soft, ragged edges and pus at the base, with tender groin lymph nodes. It differs from a syphilis sore, which is painless with firm edges.
It is now uncommon. Most genital sores are herpes or syphilis, so testing to tell them apart is always needed.
Treatment is with antibiotics, such as azithromycin 1 g by mouth as a single dose or ceftriaxone 250 mg as a single injection. Creams alone cannot cure it.
Pain eases within 3 days and the sore improves clearly within 7 days. A large sore may take more than 2 weeks.
Have blood tests for syphilis and HIV on the first day and again at 3 months, and bring partners from the 10 days before the sore for treatment too.
Frequently asked questions about chancroid
What causes chancroid?
Chancroid is caused by the bacterium Haemophilus ducreyi, spread through sex. The germ enters through tiny breaks in the genitals, anus or mouth, and a bump that breaks into a sore appears within 3–7 days. It is not caused by poor hygiene, shared toilets or certain foods. Uncircumcised men and people with several partners are at higher risk.
How many days does chancroid take to heal?
After the correct antibiotic, pain usually eases within 3 days and the sore becomes clearly smaller within 7 days. Small sores usually heal completely in 1–2 weeks, while large sores or a groin abscess may take more than 2 weeks. Uncircumcised men and people with HIV heal more slowly. If there is no improvement after 7 days, return to the doctor.
Does chancroid go away on its own?
Some sores may heal by themselves, but it takes weeks to months. During that time the sore spreads deeper, the lymph node can become an abscess and burst, and you can still pass it to partners and are more likely to catch HIV, while treatment takes only a single dose to 7 days of medicine. Do not wait for it to go away, and always have syphilis and herpes ruled out first.
Can I buy medicine for chancroid at a pharmacy and take it myself?
We do not recommend it, because most genital sores today are herpes or syphilis, which are treated differently. Some antibiotics also make a syphilis sore shrink without clearing the germ, and it later returns as a body-wide rash. The medicines doctors use for chancroid, such as azithromycin 1 g as a single dose, should be used after the doctor has examined you and taken blood tests for syphilis and HIV.
Is there a cream for chancroid, and what should I apply?
No cream can treat chancroid on its own; it needs an antibiotic taken by mouth or injection. During treatment, wash the sore twice a day with normal saline, pat it dry, and do not use alcohol or hydrogen peroxide or apply steroid cream, because they make the sore spread and heal more slowly. Antibiotic cream is used only when the doctor sees a complicating infection.
What are the symptoms of chancroid in women?
Women usually have painful sores on the labia, vaginal opening, perineum or around the anus. Some have sores inside the vagina or on the cervix that cannot be seen. The symptoms that bring them to the doctor are therefore often burning on urination, pain during sex or abnormal discharge, and some have almost no symptoms but can still pass on the infection. If you are pregnant, tell the doctor, because ciprofloxacin must not be used.
Related reading: Syphilis · Secondary syphilis rash · Genital herpes · Genital bumps · HIV rash · Genital warts · Behçet's disease
This article gives general medical information and does not replace a diagnosis by a doctor. The choice and dose of medicine depend on the examining doctor's assessment of each individual.
Written by Dr. Patara Voravutinon, Dermatologist · Last reviewed 13 November 2026
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