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penicillin G benzathine

Generic Name: penicillin G benzathine (PEN i SILL in G BEN za theen)
Brand Name: Bicillin L-A

What is penicillin G benzathine?

Penicillin G benzathine is a slow-onset antibiotic that fights bacteria in your body.

Penicillin G benzathine is used to treat many different types of severe infections, including strep infections, rheumatic fever, and syphilis.

Penicillin G benzathine may also be used for purposes not listed in this medication guide.

What is the most important information I should know about penicillin G benzathine?

You should not receive this medication if you are allergic to penicillin. Tell your doctor if you have ever had an allergic reaction to a cephalosporin antibiotic such as Ceftin, Cefzil, Omnicef, Keflex, and others.

Before you receive penicillin G benzathine, tell your doctor if you have asthma or a history of allergies, liver disease, kidney disease, or heart disease.

Be sure to receive all doses your doctor has prescribed. Your symptoms may get better before the infection is completely cleared.

After you have finished your treatment with penicillin G benzathine, your doctor may want to do tests to make sure your infection has completely cleared up.

What should I discuss with my healthcare provider before receiving penicillin G benzathine?

You should not receive this medication if you are allergic to penicillin. Tell your doctor if you have ever had an allergic reaction to a cephalosporin antibiotic such as cefdinir (Omnicef), cefprozil (Cefzil), cefuroxime (Ceftin), cephalexin (Keflex), and others.

To make sure penicillin G benzathine is safe for you, tell your doctor if you have:

  • asthma or a history of allergies;

  • liver disease;

  • kidney disease; or

  • heart disease.

FDA pregnancy category B. This medication is not expected to be harmful to an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

Penicillin G benzathine can pass into breast milk and may harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

How is penicillin G benzathine given?

Penicillin G benzathine is injected into a muscle. A healthcare provider will give you this injection.

Penicillin G benzathine must be injected slowly into a muscle of the buttock.

Penicillin G benzathine is sometimes given only once or only for a few days until your symptoms clear up. Be sure to receive all doses your doctor has prescribed. Your symptoms may get better before the infection is completely cleared. Skipping doses may also increase your risk of further infection that is resistant to antibiotics.

After you have finished your treatment with penicillin G benzathine, your doctor may want to do tests to make sure your infection has completely cleared up.

What happens if I miss a dose?

Call your doctor for instructions if you miss an appointment for your penicillin G benzathine injection.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while receiving penicillin G benzathine?

Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or bloody, stop taking penicillin G benzathine and call your doctor. Do not use anti-diarrhea medicine unless your doctor tells you to.

Penicillin G benzathine side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

  • diarrhea that is watery or bloody;

  • fever, swollen glands, rash or itching, muscle or joint pain, night sweats, general ill feeling;

  • a feeling like you might pass out;

  • skin rash with bruising, severe tingling, numbness, pain, muscle weakness;

  • pale or yellowed skin, dark colored urine, weakness;

  • easy bruising, unusual bleeding (nose, mouth, vagina, or rectum), purple or red pinpoint spots under your skin;

  • little or no urinating;

  • fast or pounding heartbeats;

  • slow heart rate, weak pulse, fainting, slow breathing;

  • confusion, agitation, hallucinations, ringing in your ears, unusual thoughts or behavior;

  • seizure (convulsions);

  • pain, swelling, bruising, irritation, or skin changes where the injection was given; or

  • hardening of your skin in the thigh where the injection was given, trouble bending your knee.

Common side effects may include:

  • nausea, vomiting;

  • blurred vision;

  • dizziness; or

  • tired feeling.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

See also: Side effects (in more detail)

Penicillin G benzathine dosing information

Usual Adult Dose for Pharyngitis:

1.2 million units IM as a single dose

Uses: For the treatment of mild to moderate upper respiratory tract infections (URTIs) due to susceptible group A streptococci (e.g., pharyngitis); for the treatment of URTIs (pharyngitis) due to group A streptococci (without bacteremia)

Infectious Diseases Society of America (IDSA) and American Heart Association (AHA) recommendations: 1.2 million units IM as a single dose

Comments:
-Preferred for patients with group A streptococcal pharyngitis who are considered unlikely to complete 10 days of oral therapy
-IDSA: This drug plus 4 days of oral rifampin are recommended for chronic carriers of group A streptococci.
-AHA: Recommended for the treatment of streptococcal tonsillopharyngitis (primary prevention of rheumatic fever)
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Upper Respiratory Tract Infection:

1.2 million units IM as a single dose

Uses: For the treatment of mild to moderate upper respiratory tract infections (URTIs) due to susceptible group A streptococci (e.g., pharyngitis); for the treatment of URTIs (pharyngitis) due to group A streptococci (without bacteremia)

Infectious Diseases Society of America (IDSA) and American Heart Association (AHA) recommendations: 1.2 million units IM as a single dose

Comments:
-Preferred for patients with group A streptococcal pharyngitis who are considered unlikely to complete 10 days of oral therapy
-IDSA: This drug plus 4 days of oral rifampin are recommended for chronic carriers of group A streptococci.
-AHA: Recommended for the treatment of streptococcal tonsillopharyngitis (primary prevention of rheumatic fever)
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Tonsillitis/Pharyngitis:

1.2 million units IM as a single dose

Uses: For the treatment of mild to moderate upper respiratory tract infections (URTIs) due to susceptible group A streptococci (e.g., pharyngitis); for the treatment of URTIs (pharyngitis) due to group A streptococci (without bacteremia)

Infectious Diseases Society of America (IDSA) and American Heart Association (AHA) recommendations: 1.2 million units IM as a single dose

Comments:
-Preferred for patients with group A streptococcal pharyngitis who are considered unlikely to complete 10 days of oral therapy
-IDSA: This drug plus 4 days of oral rifampin are recommended for chronic carriers of group A streptococci.
-AHA: Recommended for the treatment of streptococcal tonsillopharyngitis (primary prevention of rheumatic fever)
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Streptococcal Infection:

1.2 million units IM as a single dose

Uses: For the treatment of mild to moderate upper respiratory tract infections (URTIs) due to susceptible group A streptococci (e.g., pharyngitis); for the treatment of URTIs (pharyngitis) due to group A streptococci (without bacteremia)

Infectious Diseases Society of America (IDSA) and American Heart Association (AHA) recommendations: 1.2 million units IM as a single dose

Comments:
-Preferred for patients with group A streptococcal pharyngitis who are considered unlikely to complete 10 days of oral therapy
-IDSA: This drug plus 4 days of oral rifampin are recommended for chronic carriers of group A streptococci.
-AHA: Recommended for the treatment of streptococcal tonsillopharyngitis (primary prevention of rheumatic fever)
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Rheumatic Fever Prophylaxis:

1.2 million units IM once a month or 600,000 units IM every 2 weeks

Comments:
-Prophylaxis with this drug is effective in preventing recurrence of rheumatic fever and/or chorea.
-This drug has been used as follow-up prophylactic therapy for rheumatic heart disease.

Uses: Prophylaxis against rheumatic fever and/or chorea recurrence; prophylaxis for rheumatic fever after an acute attack

AHA recommendations: 1.2 million units IM every 3 to 4 weeks

Duration of secondary prophylaxis (after last attack):
-Rheumatic fever with carditis and residual heart disease (persistent valvular disease): 10 years or until 40 years of age (whichever is longer); sometimes lifelong prophylaxis
-Rheumatic fever with carditis and no residual heart disease (no valvular disease): 10 years or until 21 years of age (whichever is longer)
-Rheumatic fever without carditis: 5 years or until 21 years of age (whichever is longer)

Comments:
-Recommended for secondary prevention of rheumatic fever (prevention of recurrent attacks)
-Use every 4 weeks is appropriate for most situations; use every 3 weeks is justified and recommended for high-risk situations.
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Syphilis -- Early:

2.4 million units IM as a single dose

Uses: For the treatment of primary, secondary, and latent syphilis

US CDC recommendations:
-Primary, secondary, and early latent syphilis: 2.4 million units IM as a single dose
-Retreatment of primary or secondary syphilis (without neurosyphilis): 2.4 million units IM once a week for 3 weeks
-Late latent syphilis or latent syphilis of unknown duration: 2.4 million units IM once a week for 3 weeks (total dose: 7.2 million units)

Comments:
-A second dose (2.4 million units IM) can be administered 1 week after the initial dose to pregnant women with primary, secondary, or early latent syphilis.
-The patient's sexual partner(s) should also be evaluated/treated.
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Syphilis -- Latent:

2.4 million units IM as a single dose

Uses: For the treatment of primary, secondary, and latent syphilis

US CDC recommendations:
-Primary, secondary, and early latent syphilis: 2.4 million units IM as a single dose
-Retreatment of primary or secondary syphilis (without neurosyphilis): 2.4 million units IM once a week for 3 weeks
-Late latent syphilis or latent syphilis of unknown duration: 2.4 million units IM once a week for 3 weeks (total dose: 7.2 million units)

Comments:
-A second dose (2.4 million units IM) can be administered 1 week after the initial dose to pregnant women with primary, secondary, or early latent syphilis.
-The patient's sexual partner(s) should also be evaluated/treated.
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Neurosyphilis:

Bicillin(R) L-A: 2.4 million units IM once a week for 3 doses
Permapen(R): 3 million units IM once a week for 2 to 3 doses (total dose: 6 to 9 million units)

Use: For the treatment of late syphilis (tertiary and neurosyphilis)

US CDC recommendations:
-Tertiary syphilis with normal CSF examination: 2.4 million units IM once a week for 3 weeks (total dose: 7.2 million units)
-Neurosyphilis (after completing recommended or alternative regimen): 2.4 million units IM once a week for up to 3 weeks

Comments:
-Use of this drug can be considered after completing the recommended (aqueous penicillin G) or alternative (procaine penicillin plus probenecid) regimen for neurosyphilis to provide comparable total duration of therapy.
-The patient's sexual partner(s) should also be evaluated/treated.
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Tertiary Syphilis:

Bicillin(R) L-A: 2.4 million units IM once a week for 3 doses
Permapen(R): 3 million units IM once a week for 2 to 3 doses (total dose: 6 to 9 million units)

Use: For the treatment of late syphilis (tertiary and neurosyphilis)

US CDC recommendations:
-Tertiary syphilis with normal CSF examination: 2.4 million units IM once a week for 3 weeks (total dose: 7.2 million units)
-Neurosyphilis (after completing recommended or alternative regimen): 2.4 million units IM once a week for up to 3 weeks

Comments:
-Use of this drug can be considered after completing the recommended (aqueous penicillin G) or alternative (procaine penicillin plus probenecid) regimen for neurosyphilis to provide comparable total duration of therapy.
-The patient's sexual partner(s) should also be evaluated/treated.
-Current guidelines should be consulted for additional information.

Usual Adult Dose for Bejel:

1.2 million units IM as a single dose

Usual Adult Dose for Yaws:

1.2 million units IM as a single dose

Usual Adult Dose for Pinta:

1.2 million units IM as a single dose

Usual Adult Dose for Glomerulonephritis:

1.2 million units IM once a month or 600,000 units IM every 2 weeks

Comments: This drug has been used as follow-up prophylactic therapy for acute glomerulonephritis.

Use: Prophylaxis for glomerulonephritis after an acute attack

Usual Pediatric Dose for Bacterial Infection:

American Academy of Pediatrics (AAP) Recommendations:
Neonates and infants: 50,000 units/kg IM as a single dose

1 month or older:
-Less than 27 kg (60 pounds [lb]): 300,000 to 600,000 units IM as a single dose
-At least 27 kg (60 lb): 900,000 units IM as a single dose

Comments:
-Recommended for mild to moderate infections; primarily used for rheumatic fever prophylaxis and treponemal infections
-Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Pharyngitis:

Infants and pediatric patients less than 27.3 kg (60 lb): 300,000 to 600,000 units IM as a single dose
Older pediatric patients: 900,000 units IM as a single dose

Uses: For the treatment of mild to moderate URTIs due to susceptible group A streptococci (e.g., pharyngitis); for the treatment of URTIs (pharyngitis) due to group A streptococci (without bacteremia)

IDSA recommendations:
-Children less than 27 kg: 600,000 units IM as a single dose
-Patients at least 27 kg: 1.2 million units IM as a single dose

AHA and AAP recommendations:
-Children up to 27 kg (60 lb): 600,000 units IM as a single dose
-Patients greater than 27 kg (60 lb): 1.2 million units IM as a single dose

Comments:
-Preferred for patients with group A streptococcal pharyngitis who are considered unlikely to complete 10 days of oral therapy
-IDSA: This drug plus 4 days of oral rifampin are recommended for chronic carriers of group A streptococci.
-AHA, AAP: Recommended for the treatment of streptococcal tonsillopharyngitis (primary prevention of rheumatic fever)
-Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Upper Respiratory Tract Infection:

Infants and pediatric patients less than 27.3 kg (60 lb): 300,000 to 600,000 units IM as a single dose
Older pediatric patients: 900,000 units IM as a single dose

Uses: For the treatment of mild to moderate URTIs due to susceptible group A streptococci (e.g., pharyngitis); for the treatment of URTIs (pharyngitis) due to group A streptococci (without bacteremia)

IDSA recommendations:
-Children less than 27 kg: 600,000 units IM as a single dose
-Patients at least 27 kg: 1.2 million units IM as a single dose

AHA and AAP recommendations:
-Children up to 27 kg (60 lb): 600,000 units IM as a single dose
-Patients greater than 27 kg (60 lb): 1.2 million units IM as a single dose

Comments:
-Preferred for patients with group A streptococcal pharyngitis who are considered unlikely to complete 10 days of oral therapy
-IDSA: This drug plus 4 days of oral rifampin are recommended for chronic carriers of group A streptococci.
-AHA, AAP: Recommended for the treatment of streptococcal tonsillopharyngitis (primary prevention of rheumatic fever)
-Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Tonsillitis/Pharyngitis:

Infants and pediatric patients less than 27.3 kg (60 lb): 300,000 to 600,000 units IM as a single dose
Older pediatric patients: 900,000 units IM as a single dose

Uses: For the treatment of mild to moderate URTIs due to susceptible group A streptococci (e.g., pharyngitis); for the treatment of URTIs (pharyngitis) due to group A streptococci (without bacteremia)

IDSA recommendations:
-Children less than 27 kg: 600,000 units IM as a single dose
-Patients at least 27 kg: 1.2 million units IM as a single dose

AHA and AAP recommendations:
-Children up to 27 kg (60 lb): 600,000 units IM as a single dose
-Patients greater than 27 kg (60 lb): 1.2 million units IM as a single dose

Comments:
-Preferred for patients with group A streptococcal pharyngitis who are considered unlikely to complete 10 days of oral therapy
-IDSA: This drug plus 4 days of oral rifampin are recommended for chronic carriers of group A streptococci.
-AHA, AAP: Recommended for the treatment of streptococcal tonsillopharyngitis (primary prevention of rheumatic fever)
-Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Streptococcal Infection:

Infants and pediatric patients less than 27.3 kg (60 lb): 300,000 to 600,000 units IM as a single dose
Older pediatric patients: 900,000 units IM as a single dose

Uses: For the treatment of mild to moderate URTIs due to susceptible group A streptococci (e.g., pharyngitis); for the treatment of URTIs (pharyngitis) due to group A streptococci (without bacteremia)

IDSA recommendations:
-Children less than 27 kg: 600,000 units IM as a single dose
-Patients at least 27 kg: 1.2 million units IM as a single dose

AHA and AAP recommendations:
-Children up to 27 kg (60 lb): 600,000 units IM as a single dose
-Patients greater than 27 kg (60 lb): 1.2 million units IM as a single dose

Comments:
-Preferred for patients with group A streptococcal pharyngitis who are considered unlikely to complete 10 days of oral therapy
-IDSA: This drug plus 4 days of oral rifampin are recommended for chronic carriers of group A streptococci.
-AHA, AAP: Recommended for the treatment of streptococcal tonsillopharyngitis (primary prevention of rheumatic fever)
-Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Rheumatic Fever Prophylaxis:

AHA and AAP recommendations:
-Children up to 27 kg (60 lb): 600,000 units IM every 3 to 4 weeks
-Patients greater than 27 kg (60 lb): 1.2 million units IM every 3 to 4 weeks

Duration of secondary prophylaxis (after last attack):
-Rheumatic fever with carditis and residual heart disease (persistent valvular disease): 10 years or until 40 years of age (whichever is longer); sometimes lifelong prophylaxis
-Rheumatic fever with carditis and no residual heart disease (no valvular disease): 10 years or until 21 years of age (whichever is longer)
-Rheumatic fever without carditis: 5 years or until 21 years of age (whichever is longer)

Comments:
-Recommended for secondary prevention of rheumatic fever (prevention of recurrent attacks)
-Use every 4 weeks is appropriate for most situations; use every 3 weeks is justified and recommended for high-risk situations.
-Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Congenital Syphilis:

Less than 2 years: 50,000 units/kg IM as a single dose
2 to 12 years: Adjust dose based on adult dose schedule

Use: For the treatment of congenital syphilis (asymptomatic with normal CSF)

US CDC Recommendations:
Neonates:
-If congenital syphilis possible, less likely, or unlikely: 50,000 units/kg IM as a single dose
-Without any clinical evidence of infection (congenital syphilis possible or less likely): 50,000 units/kg IM as a single dose

Infants and children:
-If no clinical symptoms and normal evaluation: 50,000 units/kg IM once a week for up to 3 weeks
-If clinical evidence of congenital syphilis (after completing the recommended 10-day regimen): 50,000 units/kg IM as a single dose
-Without any clinical evidence of infection (congenital syphilis possible or less likely): 50,000 units/kg IM as a single dose

Maximum dose: 2.4 million units/dose

Comments:
-If possible congenital syphilis, neonates should be treated with this drug or another recommended regimen; before using this single-dose regimen, the complete evaluation (i.e., CSF analysis, long-bone radiographs, CBC with platelets) must be normal, and follow-up must be assured; if any part of the evaluation is abnormal/not performed, if the CSF analysis cannot be interpreted due to contamination with blood, or if follow-up is uncertain, 10 days of penicillin G is required. If the nontreponemal test is nonreactive and the mother's risk of untreated syphilis is deemed low, may consider the single-dose regimen to treat neonates for possible incubating syphilis without an evaluation
-If congenital syphilis is less likely, an alternative to treatment with this drug is close serologic follow-up (every 2 to 3 months for 6 months) for a neonate whose mother's nontreponemal titers declined at least 4-fold after appropriate therapy for early syphilis or remained stable for low-titer, latent syphilis.
-Treatment is not required if congenital syphilis is unlikely; use of this drug may be considered, especially if follow-up uncertain and neonate has reactive nontreponemal test.
-Infants and children with no clinical symptoms of congenital syphilis and whose evaluation (including CSF analysis) is normal: Use of this drug can be considered; a single dose can be considered after completing the recommended regimen (IV aqueous penicillin G for 10 days) to provide more comparable duration of therapy.
-Infants and children with clinical evidence of congenital syphilis: A single dose can be considered after completing the recommended regimen (procaine penicillin G for 10 days).
-Infants and children without any clinical evidence of infection: A single dose can be considered.
-Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Syphilis -- Early:

US CDC Recommendations:
1 month or older:
-Primary, secondary, and early latent syphilis: 50,000 units/kg IM as a single dose
Maximum dose: 2.4 million units/dose

-Late latent syphilis: 50,000 units/kg IM once a week for 3 weeks (total dose: 150,000 units/kg)
Maximum dose: 2.4 million units/dose (maximum total dose: 7.2 million units)

Comments: Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Syphilis -- Latent:

US CDC Recommendations:
1 month or older:
-Primary, secondary, and early latent syphilis: 50,000 units/kg IM as a single dose
Maximum dose: 2.4 million units/dose

-Late latent syphilis: 50,000 units/kg IM once a week for 3 weeks (total dose: 150,000 units/kg)
Maximum dose: 2.4 million units/dose (maximum total dose: 7.2 million units)

Comments: Current guidelines should be consulted for additional information.

Usual Pediatric Dose for Bejel:

Some experts recommend:
-Children: 600,000 units IM as a single dose

Usual Pediatric Dose for Yaws:

Some experts recommend:
-Children: 600,000 units IM as a single dose

Usual Pediatric Dose for Pinta:

Some experts recommend:
-Children: 600,000 units IM as a single dose

What other drugs will affect penicillin G benzathine?

Tell your doctor about all medicines you use, and those you start or stop using during your treatment with penicillin G benzathine, especially:

  • methotrexate;

  • probenecid;

  • birth control pills;

  • a blood thinner such as warfarin (Coumadin, Jantoven); or

  • a blood thinner such as warfarin, Coumadin; or

  • a tetracycline antibiotic--doxycycline, minocycline, tetracycline.

This list is not complete. Other drugs may interact with penicillin G benzathine, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.

Where can I get more information?

  • Your doctor or pharmacist can provide more information about penicillin G benzathine.
  • Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.
  • Disclaimer: Every effort has been made to ensure that the information provided by Cerner Multum, Inc. ('Multum') is accurate, up-to-date, and complete, but no guarantee is made to that effect. Drug information contained herein may be time sensitive. Multum information has been compiled for use by healthcare practitioners and consumers in the United States and therefore Multum does not warrant that uses outside of the United States are appropriate, unless specifically indicated otherwise. Multum's drug information does not endorse drugs, diagnose patients or recommend therapy. Multum's drug information is an informational resource designed to assist licensed healthcare practitioners in caring for their patients and/or to serve consumers viewing this service as a supplement to, and not a substitute for, the expertise, skill, knowledge and judgment of healthcare practitioners. The absence of a warning for a given drug or drug combination in no way should be construed to indicate that the drug or drug combination is safe, effective or appropriate for any given patient. Multum does not assume any responsibility for any aspect of healthcare administered with the aid of information Multum provides. The information contained herein is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. If you have questions about the drugs you are taking, check with your doctor, nurse or pharmacist.

Copyright 1996-2012 Cerner Multum, Inc. Version: 2.01.

Date modified: November 30, 2016
Last reviewed: January 21, 2013

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