What is the best medication to apply for syphilis?

There is no such thing as "what topical medication is best for syphilis." Topical treatment for syphilis should be used in conjunction with systemic therapy. Commonly used topical agents include benzathine penicillin ointment, erythromycin ointment, tetracycline ointment, mupirocin ointment, and povidone-iodine. These should be used properly according to a prescribed course after a definitive diagnosis. If symptoms suggestive of syphilis appear or there is a history of high-risk exposure, prompt medical evaluation is recommended to confirm the diagnosis.

1. Benzathine Penicillin Ointment: A penicillin-class antibiotic that inhibits the replication of *Treponema pallidum*, the bacterium causing syphilis. It is suitable for local adjunctive treatment of skin and mucous membrane lesions in early syphilis, enhancing the antibacterial effect of systemic antibiotics.

2. Erythromycin Ointment: A macrolide antibiotic effective against *Treponema pallidum*. It is suitable for local treatment in patients allergic to penicillin and can help relieve symptoms such as skin ulcers and papules.

3. Tetracycline Ointment: Works by interfering with protein synthesis in *Treponema pallidum*. It is suitable for local adjunctive treatment across all stages of syphilis, especially useful for skin lesions complicated by bacterial infection.

4. Mupirocin Ointment: Primarily used to prevent or treat secondary bacterial infections at sites of syphilitic skin lesions. It helps reduce inflammatory responses and creates favorable conditions for eliminating *Treponema pallidum*.

5. Povidone-Iodine: Has broad-spectrum antimicrobial and disinfectant properties. It can be used to clean and disinfect syphilitic skin lesions, reducing local bacterial growth and preventing secondary infections following lesion breakdown.

To promote healing, keep affected skin areas clean and dry, avoid scratching or friction to prevent worsening ulceration. Wear loose, breathable cotton clothing to minimize irritation. Abstain from sexual activity during treatment. Keep personal items separate and regularly disinfected. Maintain a light diet and avoid spicy or irritating foods.