Doxycycline Treatment For Syphilis

What is the ideal treatment for syphilis?

Both US and European health authorities recommend long-acting penicillin shots-benzathine and procaine- for the treatment of syphilis.

What makes long-acting penicillin the ideal choice for syphilis treatment?

The choice of therapy for Syphilis is not based on studies but on a historically successful response of syphilis to penicillin treatment. [1] WHO Guidelines for the Treatment of Treponema pallidum (Syphilis). https://www.ncbi.nlm.nih.gov/books/NBK384905/ No significant trials are conducted with long-acting penicillin since the medication is costly and not readily available. So, the evidence upon which recommendations for syphilis therapy are based remains inadequate.

Penicillin treatment is preferred mainly for safety reasons (fewer side effects) and the ease of getting it once a week. It is usually a one-time shot.

The main disadvantages of getting long-acting penicillin treatment are availability (it is not widely available) and cost (it costs over $700 per shot, and most insurance covers it only partially).

What is the alternative treatment for syphilis?

A few medications can be used as an alternative treatment option for syphilis treatment:

Doxycycline is considered the best alternative due to its side effects and convenience. It has been used for years and has proven effective.

What is the doxycycline regimen for syphilis treatment?

The dosage and the duration of treatment for Doxycycline depend on syphilis staging:

How effective is doxycycline treatment for syphilis?

Most of the reports about doxycycline effectiveness were from small case series, and none of the studies done included late-stage Syphilis [2] Efficacy of Doxycycline in the Treatment of Syphilis https://journals.asm.org/doi/full/10.1128/aac.01092-16 .

In addition, the study showed that people with a higher baseline RPR (what is it?) level respond better to a doxycycline regimen.

Comparing doxycycline treatment to Penicillin treatment

The overall clinical cure rate [3] Doxycycline Compared with Benzathine Penicillin for the Treatment of Early Syphilis https://academic.oup.com/cid/article/42/6/e45/287312 (what is it?) When a treatment for a medical condition makes the condition go away and it's not expected to come back for:

How the syphilis treatment assessed

The RPR level should gradually decrease over 12 months. It is usually fourfold lowerthan the initial RPR titer.

But the treatment response depends on multiple factors:

Syphilis stage (the early stages respond better)

Initial RPR level (titers <1:8 are less likely to decline fourfold than higher titers)

Patient age (the older the person, the more moderate the response to the treatment is).

Blood testing (RPR titer) and clinical evaluation (checking for rash, enlarged lymph nodes, hepatitis, and hair loss) should be done 6, 12, and 24 months after the treatment.