10 Most Common STI's, Treatment, How to Treat & Is It Cure

Updated in January 2024

Sexually-transmitted infections like gonorrhea or AIDS are spread through unprotected sexual contact (vaginal, anal or oral). It can affect both men and women of all ages.  

Generally, these infections cause symptoms that affect the genital organs. Symptoms can include pain, redness, small wounds, discharge, difficulty urinating or pain during sex. To identify the STI causing the symptoms, you should see your doctor for testing. 

Chances of getting a sexually-transmitted infection (STI) are higher when a condom is not used, when you have multiple sexual partners or from a one-night stand. 

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Which STIs are most common?

STIs that are commonly diagnosed include:

1. Chlamydia

Many people with chlamydia do not experience any symptoms and will have chlamydia without knowing, which unfortunately contributes to its spread. The condition is caused by a bacteria and can be spread through unprotected sex or through sharing of sex toys. This infection can cause thick and yellow discharge, genital redness, pelvic pain, and pain during sex. 

How to treat: Chlamydia is normally treated with antibiotics like azithromycin or doxycycline. More severe cases may require hospitalization for IV antibiotics.

Is it curable: Chlamydia can be cured, especially when treatment is fully carried out and if sexual partners are also treated.

2. Gonorrhea

Gonorrhea is an illness caused by bacteria that can occur in both men or women. It is transmitted through unprotected sex or through sharing of sex toys. Symptoms of this infection include pain with urination, yellow discharge similar to pus, vaginal bleeding (outside of a period), abdominal pain, small bumps in the mouth, or pain during sex. 

How to treat: Treatment should be done with ceftriaxone or azithromycin as prescribed by a doctor. If left untreated, gonorrhea can affect the joints and blood and can develop into a life-threatening condition. Learn more about the gonorrhea treatment your doctor may consider.

Is it curable: Gonorrhea can be cured, especially when treatment is fully carried out and if sexual partners are also treated.

3. Genital warts

Genital warts are associated with the presence of HPV, or human papilloma virus that leads to the growth of skin lesions or warts in the genital area. They can have a smooth or rough consistency and their coloration will vary with skin color. These warts are typically not painful or contagious, but they may itch, burn or peel.

Read more about what causes warts on the penis and what they can look like.

How to treat: Genital warts do not have a cure, as the HPV virus remains dormant within the body. However, you can apply topical ointments on the warts. Flare-ups of warts can occur with excessive alcohol consumption, increased fatigue and stress. Read more about how HPV is transmitted and treated. 

Is it curable: Genital warts usually resolve on their own without any specific treatment. However, treating them can help to heal the skin quicker relieve symptoms, and reduce the risk of transmission.

4. Genital herpes

Genital herpes is an easily transmitted STI that is spread through the herpes virus. It causes clusters of small red bumps, each containing yellow fluid with the virus. These clusters are usually found on the thighs, anus and sexual organs. These bumps or ulcers may also cause pain with urination, and discharge in women. Read more about the symptoms of genital herpes to determine whether your symptoms are related.

How to treat: Treatment should be completed with antivirals like acyclovir, valcyclovir or famcyclovir. These help to reduce discomfort associated with symptoms. This infection does not have a cure and symptoms can last for up to 20 days. 

Is it curable: Genital herpes is not curable, and will alternate between active wounds with remission. Treatment can be done on active ulcers, especially in its early stages, so that they can disappear more quickly. 

5. Trichomoniasis

Trichomoniasis is a parasitic infection that is not very common, It can be transmitted through sharing moist towels, through bathtubs or through sharing hot tubs. This infection causes gray or yellow-green, foamy discharge with a strong, foul odor. It can also cause redness, intense itching and swelling of sexual organs. 

How to treat: Generally, treatment for this infection is done through metronidazole or tioconazole, taken for 5 to 7 days. If left untreated, trichomoniasis can develop into other infections, trigger premature labor or lead to prostatitis. 

Is it curable: Trichomoniasis is usually cured following antibiotic treatment. If the ingection persists, there is a higher risk for other infections and pelvic inflammatory disease. 

6. Syphilis

Syphilis is an illness that can additionally also be transmitted through a contaminated blood infusion or sharing of needles. The first symptoms usually emerge 3 to 12 weeks after initial contact. This infection is associated with dry and painless wounds or red rashes on the hands and feet. this condition can eventually lead to blindness, paralysis and cardiac problems .Learn more about the phases and symptoms of syphilis

How to treat: Treatment is done with medication like penicillin or arithromycin. When taken correctly, there are greater chances for a cure. 

Is it curable: Most cases of syphilis can be cured, especially if treatment is properly followed and sexual partners are also treated.

7. Ureaplasma

This is an STI caused by Ureaplasma urealyticum bacteria. It typically causes imbalances in vaginal flora, leading to bacterial vaginosis. Symptoms incliude vaginal bleeding, pain when urinating or during sex, foul-smelling vaginal discharge and abdominal discomfort.

How to treat: Treatment is done with antibiotics such as doxycycline and ceftriaxone. In more serious cases, hospitalization and the use of antibiotics directly into the vein may also be indicated.  Ureaplasma infection can be cured, especially when treatment is carried out according to the doctor's instructions. It is also important that sexual partners follow the guidelines to prevent the person from becoming infected again.

Read more about bacterial vaginosis treatment, which can be used to eradicate the ureaplasma bacteria.

Is it curable: Ureaplasma infections are curable, especially when treatment is properly followed. However, it is also importnat for sexual partners to be treated to avoid reinfection. 


AIDS this illness does not have a cure, therefore treatment is aimed at reducing symptoms and improving quality and quantity of life.

Symptoms:  Fever, sweats, headache, light sensitivity, sore throat, vomiting and diarrhea. Read more about the symptoms of AIDS

How to treat: Treatment is done with antiretrovirals, like zidovudine or lamivudine. These medications help to reduce virus replication rate and strengthen the immune system, however they do not cure this illness. 

Is it curable: AIDS is not curable, however proper treatment can improve immunity and reduce symptom intensity, which can increase your quality of life.

9. Chancroid

Chancroid is an STI caused by Haemophilus ducreyi bacteria. These bacteria cause painful wounds with discharge in the genital area, with pus coming out. Wounds can appear between 4 and 10 days after initial contact with the bacteria.

How to treat: Chancroid is treated with antibiotics like azithromycin or ceftriaxone, as prescribed by a doctor. Chancroid can be cured as long as the treatment is carried out as prescribed.

Is it curable: To increase the chances of a cure, it is important for your sexual partner to also undergo treatment, even if they do not present with any symptoms, as this will help to prevent reinfection.

10. Granuloma inguinale

Granuloma inguinale, or donavanosis, is characterized by an infection with Klebsiella granulomatis bacteria. These cause the appearance of wounds or ulcers in the genital area that do not initially cause pain, may bleed, and increase in quantity. Due to the presence of open wounds in the region, granuloma inguinale may increases the risk of infection with other sexually transmitted infectious agents.

How to treat: Granuloma inguinale is treated with antibiotics like azithromycin, doxycycline, ciprofloxacin, trimethoprim-sulfamethoxazole and/or erythromycin. It is important to avoid sex during treatment and to abstain until the wounds have fully healed. More extensive wounds may require surgical removal. 

Is it curable: Donovanosis is cured when treatment is completed as prescribed. It is important to undergo follow-up testing to determine whether the bacteria has been totally eliminated or if the bacteria is responding to treatment. 

How to know if you have an STI 

Diagnosis of a sexually-transmitted infection can be confirmed through assessing the symptoms, inspecting the genital organs and evaluating test results. Common results are a pap test and genital swab. The doctor may also order a blood test to verify the cause for the infection and will indicate the best treatment. 

When to repeat testing

When an STI is contracted, the doctor can order testing every 6 months for the next 2 years, until 3 consecutive tests show negative results. 

During the treatment phase, it may be necessary to see your doctor several times per month to adjust treatment and cure the infection as necessary. 

How STIs can spread 

In addition to unprotected sex, STIs can also be spread in the following ways: 

  • Via blood from mother to baby, during pregnancy, breastfeeding or labor 
  • Sharing needles 
  • Sharing personal items, like towels

In some rare cases, an STI can be transmitted through a blood transfusion. 

How to prevent an STI

The best way to prevent an STI is to use a condom for all sexual activity (vaginal, anal and oral). Contact with secretions or with skin can transmit certain infections. It is important to place the condom correctly to ensure optimal protection.