Your Prescription Says Bicillin L-A — But No One Has It

If you've been prescribed Bicillin L-A (Penicillin G Benzathine) and can't find it anywhere, you're not alone. This essential antibiotic has been in shortage since 2023, with the situation worsening significantly after a major recall in July 2025. Supply remains very limited in 2026.

The good news: there are real alternatives available — both equivalent imported medications and different antibiotics that may work for your condition. Let's walk through your options.

What Is Bicillin L-A and How Does It Work?

Bicillin L-A is the brand name for Penicillin G Benzathine, a long-acting injectable antibiotic made by Pfizer. It belongs to the natural penicillins drug class.

Here's how it works: when injected into a muscle, the benzathine salt slowly dissolves and releases penicillin into your bloodstream over 2-4 weeks. The penicillin then kills bacteria by interfering with their cell wall production — without a functional cell wall, the bacteria break apart and die.

This slow-release action is what makes Bicillin L-A uniquely effective for conditions like syphilis, where you need sustained antibiotic levels over weeks. It's also why a single injection can treat what would otherwise require weeks of daily pills.

For a deeper dive, read our article: How Does Bicillin L-A Work? Mechanism of Action Explained.

Alternative 1: Extencilline (FDA-Authorized Import)

Extencilline is a benzathine benzylpenicillin injection manufactured in Europe. In January 2024, the FDA authorized its temporary importation to help address the Bicillin L-A shortage.

• Active ingredient: Benzathine benzylpenicillin — the same active ingredient as Bicillin L-A
• How it's given: Intramuscular injection, just like Bicillin L-A
• Key difference: It comes as a powder that needs to be mixed (reconstituted) before injection, rather than a prefilled syringe
• Availability: Distributed through public health channels and some healthcare facilities

Extencilline is bioequivalent to Bicillin L-A. It treats the same conditions at the same doses. If your provider offers Extencilline as a substitute, it's a medically sound alternative.

Alternative 2: Lentocilin (FDA-Authorized Import)

Lentocilin (also called Lentocilin S) is another benzathine benzylpenicillin formulation that the FDA authorized for temporary importation in March 2026 to address the ongoing and worsening shortage.

• Active ingredient: Benzathine benzylpenicillin tetrahydrate
• How it's given: Intramuscular injection
• Availability: Being distributed through healthcare systems and public health departments

Like Extencilline, Lentocilin is functionally equivalent to Bicillin L-A. The CDC has confirmed both imported products are appropriate for treating syphilis and other approved indications.

Alternative 3: Doxycycline (Oral Antibiotic)

For patients who cannot access any benzathine penicillin product and are not pregnant, Doxycycline is the main alternative for syphilis treatment.

• Drug class: Tetracycline antibiotic
• How it's taken: Oral capsule, 100 mg twice daily
• Duration: 14 days for primary and secondary syphilis; 28 days for late latent syphilis
• Availability: Widely available — Doxycycline is a common, inexpensive generic medication
• Cost: As low as $4-$20 for a course of treatment with a discount card

Important limitations:

• Not recommended during pregnancy — Doxycycline can harm the developing baby
• Requires good adherence — You need to take every dose for the full course, unlike a single Bicillin L-A injection
• Less clinical evidence supporting its use compared to benzathine penicillin

Alternative 4: Ceftriaxone (Injectable Antibiotic)

Ceftriaxone is an injectable cephalosporin antibiotic that some providers use as an alternative to Bicillin L-A.

• Drug class: Third-generation cephalosporin
• How it's given: Intramuscular or intravenous injection, 1-2 grams daily
• Duration: 10-14 days for syphilis treatment
• Availability: Generally available and not in shortage

Important limitations:

• Requires daily injections for 10-14 days, compared to a single shot of Bicillin L-A
• Less evidence for efficacy in syphilis compared to benzathine penicillin
• Possible cross-reactivity in patients with penicillin allergy (though risk is low)
• Not the CDC's first-line recommendation for syphilis

Which Alternative Is Right for You?

The best alternative depends on your specific situation:

• If you're being treated for syphilis and are pregnant: You need benzathine penicillin. Ask your provider about Extencilline or Lentocilin. No oral alternative is considered safe and effective for syphilis in pregnancy.
• If you're being treated for syphilis and are not pregnant: Doxycycline (oral) is the most practical alternative if no penicillin product is available. Ceftriaxone is another option.
• If you're being treated for strep throat: Oral Amoxicillin or Penicillin V (oral penicillin) are effective and widely available alternatives.
• If you need rheumatic fever prophylaxis: Talk to your cardiologist or infectious disease specialist about adjusting your schedule or using an imported equivalent.

No matter your situation, don't delay treatment. Work with your healthcare provider to find the best available option. You can also use Medfinder to search for pharmacies that may have Bicillin L-A or its equivalents in stock.

Final Thoughts

The Bicillin L-A shortage is frustrating, but there are real alternatives available. FDA-authorized imported equivalents like Extencilline and Lentocilin provide the same medication in a different package. For patients who can't access any benzathine penicillin, Doxycycline and Ceftriaxone offer proven backup options.

The most important thing is to get treated. Talk to your doctor, ask about all available options, and use tools like Medfinder to find what you need. For more on the shortage situation, read our Bicillin L-A shortage update for 2026.