Interim Syphilis Treatment Guidelines in the event of a Benzathine Penicillin G L-A Shortage

Background

These recommendations are intended for use during a benzathine penicillin G L-A shortage only and until further notice. They may differ from the preferred and alternative treatment recommendations in the Syphilis guide of PHAC's STBBI Guides for Health Professionals. Close clinical and/or serologic follow-up is especially important when non-penicillin regimens are used for treatment. Refer to the Treatment and Follow-up page of the Syphilis guide.

Effective immediately it is recommended that healthcare providers consider the use of benzathine penicillin G L-A be restricted to:

1. Pregnant patients (all stages)

Primary, secondary, early latent syphilis

Benzathine penicillin G 2.4 m.u. IM as a single dose

Late latent, latent of unknown duration, tertiary syphilis (not involving the central nervous system)

Benzathine penicillin G 2.4 m.u. IM weekly x 3 doses

Notes:

2. Infectious cases (primary, secondary and early latent syphilis), regardless of HIV status, if adherence to treatment and follow-up is uncertain

Benzathine penicillin G 2.4 m.u. IM as a single dose

Note:

3. Sexual contacts (within 90 days) of infectious cases of syphilis if pregnant OR adherence to treatment and follow-up is uncertain

Benzathine penicillin G 2.4 m.u. IM as a single dose

Note:

The following patients (including HIV infected) should be preferentially treated with oral doxycycline if adherence to treatment AND follow-up is expected.

1. Primary, secondary and early latent syphilis cases and their sexual contacts (non-pregnant adults)

Doxycycline 100 mg PO BID x 14 days

2. Late latent, latent of unknown duration, tertiary syphilis (not involving the central nervous system) in non-pregnant adults

Doxycycline 100 mg PO BID x 28 days

Notes:

In the event that no benzathine penicillin G L-A is available, the following treatment guidelines are recommended (including HIV infected)

1. Pregnant patients (all stages)

Penicillin G 4 m.u. IV q 4 h x 10 days

Note:

2. Primary, secondary, early latent syphilis cases and their sexual contacts (nonpregnant adults)

Doxycycline 100 mg PO BID x 14 days

Notes:

Alternative treatments

Penicillin-G 4 m.u. IV q 4 h x 10 days OR
Ceftriaxone 1 g IV q 24 h x 10 days

3. Late latent, latent of unknown duration, tertiary syphilis (not involving the central nervous system) in non-pregnant adults

Doxycycline 100 mg PO BID x 28 days

Alternative treatments

Penicillin-G 4 m.u. IV q 4 h x 10 days OR
Ceftriaxone 1 g IV q 24 h x 10 days

Notes:

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2026-03-18