What Is Trichomoniasis?

Sometimes referred to as "trich," trichomoniasis is the most common curable sexually transmitted disease (STD) found in young women.

An estimated 3.7 million people in the United States have trichomoniasis, and the infection is more common in women than in men.

Caused by a parasite, trichomoniasis can cause a foul-smelling vaginal discharge, genital itching, and painful urination.

Men often have no symptoms. In fact, only 30 percent of all people infected with trichomoniasis develop symptoms.

Trichomonas Vaginalis

Trichomoniasis is caused by the protozoan parasite Trichomonas vaginalis, which is transmitted during sexual contact.

The parasite is usually passed on from a penis to a vagina or from a vagina to a penis, but it can also be passed from a vagina to another vagina.

In women, the most commonly infected body part is the lower genital tract (vulva, vagina, or urethra), while men are most commonly infected in the inside of the penis (urethra). Men usually get it from infected women.

The parasite does not infect other body parts such as the hands, mouth, or anus.

You can reduce your risk of infection by using condoms every time you have sex.

However, since condoms don't cover everything, it's still possible to get or spread trichomoniasis even when using a condom.

Once infected with trichomoniasis, the best way to prevent reinfection is for both partners to be treated.

Risk Factors

The following may put you at greater risk for becoming infected with trichomoniasis:

• Having multiple sexual partners
• A history of other sexually transmitted diseases
• Having trichomoniasis in the past

Trichomoniasis Symptoms

About 70 percent of people with trichomoniasis don't experience any signs or symptoms. Those who do have symptoms can experience mild irritation to severe inflammation.

Generally, it can take between five and 28 days for symptoms of trichomoniasis to appear.

Symptoms may also come and go, and are different in men than in women.

Trichomoniasis in Women

Symptoms in women include:

• Itching, burning, redness, or soreness of the genitals
• Discomfort with urination
• Thin foul-smelling discharge that can be clear, white, yellowish, or greenish
• Unpleasant sensations during sex
• Lower abdominal pain in rare cases

Menstruations may exacerbate symptoms.

Trichomoniasis in Men

Symptoms of trichomoniasis in men include:

• Itching or irritation inside the penis
• Burning after urination or ejaculation
• Discharge from the penis after urination or ejaculation
• Unpleasant sensations during sex

If you have any of the above symptoms, stop having sex and call your doctor immediately.

Diagnosis

A healthcare provider cannot diagnose trichomoniasis based solely on your symptoms.

For both men and women, the provider may examine you and order a laboratory test to diagnose the infection.

In men, trichomoniasis can be confirmed through a urine sample.

In women, a healthcare provider may do a pelvic exam that may allow him or her to see small red sores inside the vagina or cervix.

The provider may also take a fluid sample from the vagina to have it tested for the parasite.

A vaginal culture or DNA test can also be used to detect trichomoniasis.

If you have trichomoniasis, ask your healthcare provider if you should also be tested for other STDs.

Trichomoniasis Treatment

If left untreated, trichomoniasis can last for months or even years. But trichomoniasis usually can be cured with a single dose of the following prescription antibiotics:

• Metronidazole (Flagyl)
• Tinidazole (Tindamax)

Do not drink alcohol for at least 24 hours after taking metronidazole or 72 hours after taking tinidazole, as this may cause severe nausea and vomiting.

Other medication side effects may include:

• Headache
• Metallic taste
• Dizziness

Even if you have been treated for trichomoniasis, you can still get it again.

In fact, about one in five people get infected again within three months after treatment.

If you're being treated for trichomoniasis, you should not have sex until you no longer have symptoms and all of your sex partners have been tested and treated.

Complications

Pregnant women with trichomoniasis may be affected in the following ways:

• Deliver prematurely
• Have a baby with a low birth weight
• Transmit the infection to the baby as it passes through the birth canal

To avoid complications, pregnant women can safely take metronidazole or tinidazole to treat trichomoniasis, if prescribed by their doctor.

Having trichomoniasis can also cause genital inflammation that makes it easier to get infected with HIV, the virus that causes AIDS, or to pass the HIV virus to a sex partner.