Trichomoniasis (trich) is a sexually transmitted infection (STI) caused by a single-celled organism (protozoa).

Although men with trich rarely have symptoms, they may experience penis discharge, burning during urination, and irritation and redness of the head of the penis.

Women are more likely than men to have symptoms. Common symptoms for women with trich include:

• Large amounts of yellowish green, sometimes foamy discharge from the vagina.
• Vaginal itching or irritation.
• Unusual vaginal odor.
• Patchy red areas around the vagina.
• Pain during sexual intercourse.
• Painful or frequent urination.

Trichomoniasis is easily treated with medicine. Treating the sex partners of infected people increases the cure rate and reduces the possibility of reinfection or further spread of the disease.