Four sexually transmitted infections are currently curable: chlamydia, gonorrhea, syphilis, and trichomoniasis. All four can be eliminated from your body with antibiotics, often in a single dose or a short course of treatment. The remaining common STIs, including HIV, herpes, hepatitis B, and HPV, are viral infections that can be managed but not cured with current medicine. Globally, more than 1 million new curable STI infections are acquired every day among people aged 15 to 49.
The Four Curable STIs
The distinction between curable and incurable STIs comes down to biology. The four curable infections are caused by either bacteria or parasites, which antibiotics can kill outright. Viral STIs, by contrast, insert their genetic material into your cells, where medications can suppress them but not fully eliminate them.
Chlamydia
Chlamydia is the most commonly reported bacterial STI. It often causes no symptoms at all, which is why routine screening matters. A seven-day course of oral antibiotics is the standard treatment. With a single-dose alternative, you need to wait one week before having sex again. With the seven-day course, you can resume sexual activity the day after finishing your last pill.
Gonorrhea
Gonorrhea is cured with a single antibiotic injection. If a chlamydia co-infection hasn’t been ruled out, your provider will typically add a week of oral antibiotics, since the two infections frequently occur together. One important caveat: gonorrhea has developed resistance to nearly every class of antibiotic that has been used against it over the decades. The current recommended injection remains effective, but resistance is an ongoing concern, which is why following the full treatment protocol matters.
Syphilis
Syphilis progresses through distinct stages if left untreated, but in its early stages (primary and secondary), a single injection of penicillin cures it. If syphilis has gone undetected longer and reached the latent stage, treatment requires a series of weekly injections over three weeks. Syphilis is fully curable at any stage, though treatment in later stages is more involved and any organ damage that has already occurred may not be reversible.
Trichomoniasis
Trichomoniasis is caused by a parasite rather than bacteria, but it’s still treated with oral medication. The treatment regimen differs slightly by sex. For women, a seven-day twice-daily course has cure rates of roughly 84% to 98%. For men, a single larger dose is standard. An alternative medication achieves cure rates of 92% to 100%. Trichomoniasis is extremely common and, like chlamydia, often produces no symptoms, particularly in men.
Why Viral STIs Can’t Be Cured
The four major viral STIs, HIV, herpes (HSV), hepatitis B, and HPV, behave fundamentally differently from bacterial or parasitic infections. Viruses embed themselves into your body’s cells, essentially hiding from your immune system in ways that antibiotics can’t reach. For HIV and herpes, antiviral medications suppress the virus and reduce symptoms, but they don’t eradicate the underlying infection. When someone with herpes stops antiviral therapy, the virus can reactivate because it remains dormant in nerve cells. HIV treatment works similarly: daily antivirals can reduce the virus to undetectable levels, but the infection persists if treatment stops.
HPV is a partial exception. While there’s no medication that kills the virus, your immune system clears roughly 80% to 90% of HPV infections on its own within two years. About 43% of infections clear within just six months. The concern is with the minority of infections that persist, which can lead to cervical or other cancers over time. Vaccination before exposure prevents the highest-risk strains entirely.
Hepatitis B can also be cleared naturally by the immune system in many adults, though some people develop chronic infections that require long-term antiviral treatment to limit liver damage.
What Happens After Treatment
Being cured means the infection is completely gone from your body, but it doesn’t mean you’re immune. You can be reinfected with any of the four curable STIs immediately after successful treatment. This is common enough that the CDC recommends retesting three months after treatment for chlamydia, gonorrhea, or trichomoniasis to catch repeat infections early. Sexual partners need to be treated at the same time, or you risk passing the infection back and forth.
The waiting period before sex varies by infection and treatment type, but generally ranges from one day after completing a multi-day antibiotic course to one week after a single-dose treatment. Your provider will give you a specific timeline.
Risks of Delaying Treatment
The fact that these STIs are curable doesn’t make them harmless if ignored. Untreated chlamydia and gonorrhea can cause pelvic inflammatory disease in women, a condition where infection spreads to the uterus and fallopian tubes. About 1 in 8 women with a history of pelvic inflammatory disease have difficulty getting pregnant afterward. The damage includes scar tissue in the fallopian tubes, which can block eggs from reaching the uterus or cause life-threatening ectopic pregnancies. Long-term pelvic pain is another common consequence.
Untreated syphilis can progress over years to affect the brain, heart, and other organs. Untreated gonorrhea can spread to the blood and joints. Because many of these infections produce no symptoms in their early stages, the only reliable way to catch them is through regular screening, particularly if you have new or multiple sexual partners.
The core takeaway is straightforward: chlamydia, gonorrhea, syphilis, and trichomoniasis are all completely curable with the right treatment taken promptly. The biggest risk with curable STIs isn’t the infection itself; it’s not knowing you have one.