October '25 Infectious Diseases Update

Posted by Doug Black, PharmD., Ann Lloyd, PharmD. on Oct 17th 2025

OCTOBER 2025

Article of the Month (Editors' Choice)

One Dose versus Three Doses of Benzathine Penicillin G in Early Syphilis
By Henry F. Chambers, MD

The phrase "One night with Venus, a lifetime with Mercury" originates from the use of mercury, recommended by the 16th century Swiss physician, Paracelsus, for the treatment of syphilis*. Dubious in efficacy, certain in toxicity, mercury was standard of care until the introduction of salvarsan, an arduous treatment in its own right, in the early 20th century.
More than 80 years after its introduction into clinical practice, the study of Hook, et al. (N Engl J Med 2025;393:869) reaffirms the miracle of penicillin for curing syphilis. This study demonstrates yet again that a single intramuscular dose of 2.4 million units of benzathine penicillin G* is highly efficacious for early (i.e., primary, secondary, or early latent) syphilis and just as good as three doses, including for patients with HIV.
While the regimen of three doses of benzathine penicillin G administered one week apart is hardly a lifetime, it is inconvenient, three times the pain of a single shot, and most importantly, unnecessary. Good to know, given the recurrent shortages of benzathine penicillin G.

Recent Drug Approvals

Clotic (clotrimazole 1% otic solution) for the treatment of fungal otitis externa due to Aspergillus spp. and Candida spp. in patients 18 years of age and older. The product is packaged in single-dose vials with a deliverable volume of approximately 0.17 mL (1.7 mg of clotrimazole). Recommended dose: instill contents of one vial into the affected ear canal q12h for 14 consecutive days.

New or Updated Practice Guidelines

CDC recommendations to US healthcare providers and preparedness personnel regarding treatment and postexposure prophylaxis of tularemia* (MMWR Recomm Rep 2025;74:1-33). PDF available for download.
British Association of Sexual Health and HIV (BASHH) UK national guideline for the management of Neisseria gonorrhoeae*, 2025 (Int J STD AIDS 2025;36:826-840). This is an update of the 2018 guidelines. Key changes:
- Pharyngeal testing is recommended for all individuals with urogenital gonorrhea, and all contacts.
- Updated recommendations for diagnosing disseminated gonococcal infection and managing ocular infection.
- Ciprofloxacin is no longer recommended as first-line therapy due to safety concerns, but may be used if clinically appropriate.
- Cefixime dose increased from 400 mg x1 to 400 mg x2 (6-12 hr apart), due to rising antimicrobial resistance.
- Routine test of cure is not necessary for anogenital infections treated with ceftriaxone 1 gm if infection is susceptible to ceftriaxone.

COVID 2025-2026 Vaccines

The following COVID vaccines have FDA approval for 2025-26 (as of August 28, 2025):
- Spikevax (LP.8.1 variant, standard dose; Moderna) is approved for >6 months old with medical conditions and everyone >65 years.
- mNexspike (LP.8.1 variant, low dose; Moderna) is approved for >12 years old with medical conditions and everyone >65 years.
- Comirnaty (LP.8.1 variant, standard dose; Pfizer) is approved for >5 years old with medical conditions and everyone >65 years.
- Nuvaxovid (JN.1 variant, same as 2024-2025 vaccines; Novavax) is approved for >12 years old with medical conditions and everyone >65 years.
In the package insert for all products, section 8.1 (Pregnancy), Clinical Considerations:
- "Pregnant individuals infected with SARS-CoV-2 are at increased risk of severe COVID-19 compared with non-pregnant individuals" with no further specific instruction.
ACIP published the following language on October 7, 2025:
- Adults 65+: Vaccination based on individual-based decision-making. 2 doses per year.
- Individuals 6 months to 64 years: Annual vaccination based on individual-based decision-making, with an emphasis that the risk-benefit of vaccination is most favorable for individuals who are at an increased risk for severe disease.
  - Pregnancy included on CDC risk factor list.
- Additional dose for certain underlying medical conditions.
Any changes to 2024-5 COVID-19 vaccine dosage and risk factor wording for 2025-6 await official CDC publication.
- CDC websites still say "This page’s contents are being revised to reflect updated recommendations recently made by ACIP and approved by CDC."
2025 recommendations from authoritative professional bodies:
- American Academy of Pediatrics (AAP): Recommended Child and Adolescent Immunization Schedule
- American College of Obstetrics and Gynecology (ACOG): Maternal Immunization Guidance for COVID-19, Influenza, and RSV
- American Academy of Family Practice (AAFP): lmmunization Schedules
Many pharmacies and clinical facilities are not providing COVID vaccination due to discrepancies between FDA, CDC, HHS press releases, and professional organizations.

Antimicrobial Stewardship

Using a Microbiology Intervention to Guide Prescribing

A recent single-center study evaluated the use of a microbiology comment developed to optimize antibiotic use for Streptococcus pneumoniae bloodstream infections (BSI).
The intervention involved the automatic display of a comment on rapid blood polymerase chain reaction results for S. pneumoniae. The comment suggested ampicillin IV or penicillin IV as the drugs of choice for non-meningitis infections and max dose ceftriaxone IV plus vancomycin IV for meningitis until susceptibilities known. Education was also provided to the pharmacy department and providers.
De-escalation to ampicillin or penicillin within 48 hours was seen in 66.7% of the intervention group compared with 29.6% of the pre-intervention group (P<0.001). In the intervention group, oral switch occurred more often and broad-spectrum duration of therapy was shorter. There was no difference in hospital length of stay, all-cause mortality, or all-cause readmission between the groups.
Stewardship teams can use the results of this study to design microbiology interventions to guide optimal antibiotic prescribing. Antimicrob Steward Healthc Epidemiol. 2025, e203.

Antimicrobial Shortages (US)

New shortages:
- None
Resolved shortages:
- Mefloquine 250 mg tablets (18 Sep 2025)
Antimicrobial drugs recently discontinued:
- Bezlotoxumab injection (31 Jan 2025, by Merck)
Antimicrobial drugs or vaccines in continued reduced supply or unavailable due to increased demand, manufacturing delays, product discontinuation by a specific manufacturer, or unspecified reasons:
- Antibacterial drugs:
  - Aminoglycosides:
    - Gentamicin injection (22 Feb 2021)
  - Bacitracin ophthalmic ointment 500 units/gm (12 Sep 2024)
  - Cephalosporins:
    - Cefazolin injection (4 Jun 2018)
    - Cefdinir 300 mg capsules (29 Jun 2023)
    - Cefdinir 125 mg/5 mL, 250 mg/5 mL oral suspension (29 Jun 2023)
    - Cefotaxime injection (10 Jun 2015)
      - FDA is allowing temporary importation of product from SteriMax in Canada, in conjunction with Provepharm Life Solutions and its distributor Direct Success.
  - Chloramphenicol injection (9 Oct 2023)
  - Fluoroquinolones:
    - Levofloxacin injection in D5W (29 May 2024)
    - Levofloxacin oral solution, 25 mg/mL (15 Sep 2023)
    - Moxifloxacin 400 mg tablets (6 Dec 2023)
  - Glycopeptides, glycolipopeptides, lipopeptides:
    - Vancomycin injection (1 Jun 2015)
  - Lincosamides
    - Clindamycin phosphate injection (25 Jun 2015)
  - Macrolides, azalides:
    - Azithromycin oral suspension, 1 gm packets (20 Nov 2024)
    - Erythromycin lactobionate injection (23 Apr 2025)
  - Neomycin and Polymyxin B sulfates GU irrigant (25 Jun 2023)
  - Nitrofurantoin oral suspension (5 Jun 2018)
  - Nitroimidazoles:
    - Metronidazole injection (20 Oct 2021)
  - Oxazolidinones:
    - Linezolid injection (16 Oct 2024)
  - Penicillins:
    - Amoxicillin, all oral formulations (18 Oct 2022)
    - Amoxicillin-clavulanate, all oral formulations (17 Nov 2022)
    - Dicloxacillin 250 mg, 500 mg capsules (18 Aug 2021)
    - Penicillin G benzathine injection (1 Feb 2023) Availability update
      - Temporary importation of Extencilline from France
      - Temporary importation of Lentocilin from Portugal
    - Penicillin G benzathine/Penicillin G procaine (31 Mar 2023) Availability update
    - Penicillin VK oral solution 250 mg/5 mL (17 May 2023)
    - Penicillin VK 250 mg, 500 mg tablets (17 May 2023)
  - Rifaximin 200 mg tablets (11 Apr 2024)
- Antifungal drugs:
  - Amphotericin B Lipid Complex (5 Aug 2022)
  - Ibrexafungerp 150 mg tablets (3 Dec 2024)
- Antimycobacterial drugs:
  - No current shortages
- Antiparasitic drugs:
  - Nitazoxanide oral susp 100 mg/5 mL (15 Feb 2024)
- Antiviral drugs:
  - Oseltamivir 30 mg, 45 mg, 75 mg capsules (1 Nov 2022)
  - Oseltamivir powder for oral suspension (1 Nov 2022)
  - Peginterferon alfa-2a (Pegasys) (8 Jan 2025)
  - Ribavirin for inhalation solution (23 May 2023)
For more information including estimated resupply dates, see ASHP Drug Shortages website.
Data shown are current as of 12 Oct 2025.