How Effective Is Doxycycline for Syphilis?

The antibiotic drug doxycycline is considered an effective treatment for syphilis, a potentially fatal sexually transmitted disease (STD). The most commonly used treatment for this disease is penicillin, but doxycycline typically comes in a close second and is used if a person is allergic to or does not have access to penicillin. Despite the fact that this antibiotic is considered effective for fighting syphilis, it usually requires extended treatment. For example, a patient may be instructed to take 200 mg of this drug daily for 20 or more days. It is important to note that waiting to begin treatment for syphilis may render doxycycline ineffective — successful treatment is typically dependent on recognition and treatment of the disease in its early stages.

While using doxycycline for syphilis is effective, it is not the preferred treatment for this potentially deadly STD. Doctors usually prefer treatment with the antibiotic penicillin. A doctor might prescribe doxycycline instead, however, when a person needs treatment but cannot take penicillin. For example, it could be used for patients who are allergic to penicillin or when penicillin is unavailable in the region.

If a person is using doxycycline for syphilis, it is usually considered effective during the first and second stages of the disease. If treatment begins during a late stage of syphilis, the patient will most likely have suffered damage to his organs. Treatment at this stage may help to prevent additional damage to one's organs, but it cannot fix the damage a person has already experienced. This is the reason doctors recommend seeking treatment as soon as possible.

Doctors usually prescribe about 200 mg of doxycycline for syphilis treatment for those who are beginning the regimen in the early stages of the disease, and patients often take it daily for about 20 days. For latent-stage syphilis, which is a period marked by a lack of symptoms, the dosage is often the same: 200 mg. Typically, however, patients must continue taking the medication for a longer period of time when treatment begins in the latent stage. For example, doctors may instead recommend treatment for 30 days. Doctors usually perform blood tests after treatment to determine how effective the medication has been, and sometimes repeat treatment is necessary.

The effective use of doxycycline for syphilis means taking the entire course of medication a doctor prescribes. If a person fails to do so, the bacteria that causes this STD can become resistant to antibiotics. As a result, it can prove much more difficult to treat.