Comprehensive medication guide to Lentocilin including estimated pricing, availability information, side effects, and how to find it in stock at your local pharmacy.
Estimated Insurance Pricing
Covered through the medical benefit (not pharmacy) when administered by a provider. Medicare Part B patients typically pay 20% coinsurance after deductible; Medicaid covers it with minimal copay. Most private plans cover the injection as a medical procedure.
Estimated Cash Pricing
Lentocilin from Cost Plus Drug Company is approximately $15 per dose for healthcare businesses; the US equivalent Bicillin L-A can exceed $500 per dose at retail. For patients, the actual cost depends on the clinical setting — public health STI clinics often provide treatment at low or no cost.
Medfinder Findability Score
28/100
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Lentocilin is a brand name for benzathine benzylpenicillin (penicillin G benzathine), a long-acting injectable antibiotic belonging to the natural penicillin class. It is manufactured in Portugal by Laboratórios Atral S.A. and is currently imported into the United States under FDA enforcement discretion to address the severe shortage of Bicillin L-A — the domestically manufactured equivalent made by Pfizer.
Lentocilin is the gold standard treatment for syphilis at all stages and the only recommended treatment for syphilis during pregnancy. A single injection creates a slow-release depot in the muscle, maintaining therapeutic penicillin blood levels for 2–4 weeks. It is also used for Group A streptococcal infections, rheumatic fever prophylaxis, and tropical diseases such as yaws, bejel, and pinta.
Lentocilin differs from Bicillin L-A in several important ways: it comes as a powder requiring reconstitution (not a prefilled syringe), its diluent contains lidocaine 1.5%, it contains soy phospholipids, and the reconstituted volume per 1,200,000-unit dose is 4 mL versus 2 mL for Bicillin L-A. It is not FDA-approved and is distributed in the US by Mark Cuban Cost Plus Drug Company and TopRx.
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Lentocilin's active ingredient — penicillin G — is a beta-lactam antibiotic that kills bacteria by irreversibly binding to penicillin-binding proteins (PBPs), enzymes that bacteria use to build and maintain their cell walls. When these enzymes are blocked, bacteria cannot repair or construct their cell wall, causing the cell to swell and rupture. Because human cells lack cell walls, penicillin is highly selective for bacteria and generally safe for human cells.
The 'benzathine' component of Lentocilin is a water-insoluble salt that creates a slow-release depot when injected into the muscle. The body absorbs tiny amounts of penicillin continuously from this depot over 2–4 weeks, maintaining low but persistent blood levels. This long-acting property is critical for treating syphilis, whose causative bacterium (Treponema pallidum) divides very slowly (approximately every 30 hours), requiring sustained antibiotic exposure over an extended period.
Notably, Treponema pallidum has never developed confirmed resistance to penicillin in over 80 years of clinical use, making Lentocilin uniquely reliable for syphilis treatment in an era of increasing antibiotic resistance. However, the blood levels produced by the benzathine formulation are not sufficient to cross the blood-brain barrier — IV penicillin G is required for neurosyphilis.
1,200,000 units — powder for suspension for injection
Single vial with 4 mL lidocaine 1.5% diluent; reconstituted volume = 4 mL
2,400,000 units — two-vial dose (administered at two separate sites)
Used for early syphilis (single visit) and late latent/tertiary syphilis (weekly x3)
Finding Lentocilin in 2026 is extremely challenging. The Bicillin L-A shortage — the drug Lentocilin was imported to replace — began in mid-2023 and has worsened significantly. In July 2025, Pfizer recalled multiple lots of Bicillin L-A due to particulates, and as of April 2026, Pfizer has pushed the full shortage recovery to Q4 2027. Lentocilin supply itself is intermittent — there have been periods where it was unavailable from its authorized U.S. distributor for weeks at a time.
Lentocilin cannot be picked up at a standard retail pharmacy for self-administration. It must be administered by trained healthcare staff via deep intramuscular injection at a clinic, hospital, or public health facility. Public health STI clinics and health departments receive priority allocations and are often the most reliable source. Federal and state health departments have also implemented patient prioritization strategies to ensure the most vulnerable patients — especially pregnant women and newborns — receive treatment.
To find Lentocilin near you, medfinder contacts pharmacies and healthcare facilities in your area to check which ones have your medication in stock — saving you hours of calling around during an already stressful situation.
Lentocilin (penicillin G benzathine) is not a controlled substance and has no special DEA prescribing requirements. Any licensed healthcare provider with standard prescribing authority can order it. Because it must be administered by trained staff via deep intramuscular injection, the key constraint is finding a facility that has both the drug in stock and the clinical staff to administer it.
Types of providers who commonly prescribe Lentocilin include:
Infectious disease specialists
OB/GYN physicians
Primary care physicians and internists
Pediatricians
STI clinic providers (public health physicians, NPs, PAs)
Cardiologists (for rheumatic fever prophylaxis patients)
Emergency medicine physicians
Nurse practitioners and physician assistants (in most states)
Telehealth providers can write a Lentocilin prescription after reviewing test results remotely, but the injection itself must be given in person at a clinic, STI clinic, hospital, or public health facility. Sexual health-focused telehealth platforms (such as Planned Parenthood Direct, Wisp, or Hey Jane) can help with the prescription step quickly.
No. Lentocilin (penicillin G benzathine) is not a DEA scheduled controlled substance. It requires a standard prescription from a licensed healthcare provider, but it has no DEA scheduling requirements, no refill restrictions specific to controlled substance status, and no special prescribing authority requirements beyond a standard medical license. Any physician, nurse practitioner, or physician assistant licensed to prescribe can order Lentocilin without DEA registration for this specific drug.
Because Lentocilin is an injectable antibiotic administered in clinical settings, access is practically limited by which facilities have trained staff and current stock — not by prescription regulations. The primary access challenge in 2026 is the national shortage of penicillin G benzathine products, not regulatory restrictions.
Most side effects of Lentocilin are mild and related to the injection itself:
Injection site pain, soreness, and swelling (1-3 days)
Induration (firm lump) at the injection site (may last weeks)
Mild skin rash, itching (urticaria, pruritus)
Jarisch-Herxheimer reaction when treating syphilis (fever, chills, headache within 2-8 hours of first dose — not an allergic reaction)
Anaphylaxis (rare, ~0.05%): difficulty breathing, throat swelling, rapid heartbeat, loss of consciousness — call 911
Soy allergy reaction (Lentocilin-specific): Lentocilin contains soy phospholipids; patients with soy allergy may experience severe hypersensitivity
Cardiorespiratory arrest if accidentally given intravenously — must ONLY be administered by deep IM injection
C. difficile colitis: severe diarrhea during or up to 2 months after treatment
Sciatic nerve injury if injection technique is incorrect
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Doxycycline
First-line CDC-recommended alternative for non-pregnant adults with syphilis; 100mg PO BID x14 days (early) or 28 days (late latent). Widely available oral pill — not safe in pregnancy.
Ceftriaxone
Third-generation cephalosporin; used for primary/secondary syphilis in non-pregnant adults when other options unavailable. Limited evidence base; given IV or IM. Caution in penicillin-allergic patients.
Amoxicillin
Oral penicillin; appropriate alternative for strep pharyngitis (500mg BID x10 days). Not a substitute for syphilis treatment.
Penicillin V (Penicillin VK)
Oral natural penicillin; appropriate for strep pharyngitis and rheumatic fever prophylaxis when injectable supply is unavailable. Not for syphilis treatment.
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Methotrexate
majorPenicillins reduce renal excretion of methotrexate, causing potentially toxic blood level increases. Monitor closely if concurrent use is unavoidable.
Oral contraceptives
moderatePenicillins may theoretically reduce contraceptive efficacy by altering gut flora. Advise backup contraception during treatment and for 7 days after.
Probenecid
moderateReduces renal secretion of penicillin, prolonging blood levels. Sometimes used therapeutically; monitor if patient takes probenecid for gout.
Bacteriostatic antibiotics (tetracyclines, chloramphenicol)
moderateMay antagonize bactericidal activity of penicillin by slowing bacterial growth. Avoid concurrent use unless specifically indicated.
Warfarin / anticoagulants
moderatePenicillin can alter gut flora affecting Vitamin K synthesis, potentially changing INR. Monitor INR more frequently if on warfarin.
Lentocilin is a critical medicine — the only effective treatment for syphilis during pregnancy and the gold standard for syphilis treatment generally. The current shortage, stemming from the Bicillin L-A supply crisis that began in 2023 and worsened dramatically with the 2025 recall, represents one of the most serious drug supply disruptions in recent U.S. public health history. With Pfizer's recovery now projected for Q4 2027, Lentocilin remains the primary alternative for the foreseeable future.
If you or a patient needs Lentocilin, act quickly: contact your local STI clinic or health department first, as they receive priority allocations. For non-pregnant adults who cannot access Lentocilin, doxycycline is a CDC-recommended alternative for syphilis. Pregnant patients should never be left without treatment — escalate through state health department channels and Pfizer's medical request process if needed.
Don't spend hours calling every clinic in your area. Use medfinder to quickly identify which facilities near you have Lentocilin in stock and can administer it, so you can focus on getting treated rather than navigating an already complex shortage.
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