Why Is Lentocilin So Hard to Find? [Explained for 2026]

You walked into a clinic or called your pharmacy looking for Lentocilin — and came up empty. Maybe you were prescribed it to treat syphilis, strep throat, or to prevent rheumatic fever. Whatever the reason, you're not alone. Lentocilin (penicillin G benzathine) has been extremely difficult to find across the United States since mid-2023, and the situation has only grown more complicated through 2025 and into 2026.

Here's the full picture of why this critical antibiotic is so hard to obtain — and what you can do about it.

What Is Lentocilin and Why Does It Matter?

Lentocilin is a brand name for benzathine benzylpenicillin (penicillin G benzathine), a long-acting injectable antibiotic manufactured in Portugal by Laboratórios Atral S.A. It was not originally sold in the United States — it was imported temporarily by Mark Cuban's Cost Plus Drug Company starting in July 2024, with FDA authorization, specifically to address a severe shortage of the US equivalent: Bicillin L-A.

Penicillin G benzathine (the active ingredient in Lentocilin) is the only recommended first-line treatment for syphilis in most patients, and the only safe option for pregnant women with syphilis. No other antibiotic can substitute it in pregnancy. This is why the shortage — and finding Lentocilin — is not just an inconvenience. For many patients, it's a medical emergency.

Why Is There a Shortage in the First Place?

The root cause of the Lentocilin supply crunch is the ongoing shortage of Bicillin L-A — the FDA-approved U.S. version of this drug. Lentocilin was brought in specifically to fill that gap, which means it is downstream of the same supply and demand pressures. Here are the key factors:

1. Syphilis Rates Have Surged to Historic Highs

Syphilis rates in the United States reached levels not seen in decades. Congenital syphilis — transmitted from mothers to newborns — hit its highest rate in 30 years by 2023. This dramatic increase in cases created massive surging demand for penicillin G benzathine at a time when supply was already strained.

2. A Single Domestic Manufacturer

In the United States, Bicillin L-A is made by only one manufacturer: King Pharmaceuticals LLC, a subsidiary of Pfizer. When Pfizer encountered production constraints and demand outstripped supply beginning in mid-2023, there was no domestic backup source. The FDA listed Bicillin L-A as being in shortage in 2023, and the situation has worsened since.

3. The July 2025 Recall Made Things Worse

In July 2025, King Pharmaceuticals (Pfizer) issued a voluntary recall of multiple lots of Bicillin L-A 1.2 and 2.4 million unit prefilled syringes due to particulates found in the product. This recall pulled significant inventory from the market and pushed the expected recovery of the shortage even further. As of April 2026, Pfizer has pushed the anticipated recovery date to Q4 2027.

4. Lentocilin's Own Supply Is Intermittent

Lentocilin was imported as an emergency measure, not a permanent solution. Distribution runs through a limited set of channels (primarily TopRx as authorized distributor). When those stocks run out, there is no immediate resupply. As of late 2025, Lentocilin was temporarily unavailable to order through wholesalers, and the FDA again approved renewed importation in March 2026. This cycle of availability and outages makes Lentocilin difficult to plan around for clinics and patients alike.

5. Lentocilin Is Not Available at Retail Pharmacies

Unlike most medications, Lentocilin (and Bicillin L-A) are injectable antibiotics that must be administered by a trained healthcare professional via deep intramuscular injection. They are not dispensed over the counter or filled at your local chain pharmacy for self-administration. Instead, you need to find a clinic, hospital, STI clinic, or public health department that has the drug in stock AND can administer it. This adds an extra layer of difficulty compared to finding, say, a typical oral antibiotic.

Who Is Most Affected by the Shortage?

Several groups face the most critical impact from the limited supply of Lentocilin and Bicillin L-A:

Pregnant women with syphilis: Penicillin G benzathine is the ONLY recommended treatment. There is no safe substitute in pregnancy.

Newborns with congenital syphilis: Penicillin is the essential treatment for infants born with or exposed to syphilis in utero.

Patients with syphilis who can't take doxycycline: Some people cannot use the main alternative antibiotic due to allergies or other conditions.

Patients on rheumatic fever prophylaxis: Monthly Lentocilin injections are used to prevent recurrent rheumatic fever, and interruptions in supply put these patients at risk.

What Can You Do If You Can't Find Lentocilin?

The key steps to take if you're struggling to find Lentocilin or penicillin G benzathine:

Contact your local STI clinic or public health department. These facilities often receive priority allocations of penicillin G benzathine products during shortages. They may have Lentocilin or Bicillin L-A when private pharmacies and clinics do not.

Ask your provider about alternatives. For non-pregnant adults with syphilis, doxycycline (100 mg twice daily for 14-28 days) is the CDC-recommended alternative when penicillin G benzathine is unavailable. Ceftriaxone is another option with limited supporting data.

Use medfinder to locate it near you.

medfinder contacts pharmacies and clinics near you on your behalf to find which ones have your medication in stock.

Talk to an infectious disease specialist. If you have a complex case or cannot access first-line treatment, an ID specialist can help navigate the shortage and identify the safest alternatives for your situation.

What's the Outlook for 2026 and Beyond?

The situation remains challenging. Pfizer's Bicillin L-A recovery is now projected for Q4 2027 — over a year away from the time of writing. Lentocilin importation has been re-authorized by the FDA as of March 2026 to help bridge the gap, but distribution is limited and supply is not guaranteed to be consistent.

Public health experts and advocates continue to push for a long-term domestic solution to ensure the U.S. is never again left without access to this critical antibiotic. For now, working with your healthcare provider, your local health department, and tools like medfinder is the best way to navigate the shortage and get the treatment you need.

Further Reading

Lentocilin Shortage Update: What Patients Need to Know in 2026

Alternatives to Lentocilin If You Can't Fill Your Prescription

How to Find Lentocilin in Stock Near You: Tools and Tips