Benzathine

Benzathine is a prescription medication used to treat Group A Streptococcal Respiratory Infections, Syphilis, Yaw, Bejel and Pinta and for the prevention of Rheumatic Fever.

• Benzathine is available under the following different brand names: Bicillin LA, Permapen

Adult and pediatric dosage

Injectable suspension

• 600,000 units/1mL
• 1.2 million units/2mL
• 2.4 million units/4mL

Group A Streptococcal Respiratory Infections

Adult dosage

• 1.2 million U IM once

Pediatric dosage

• Children weighing less than 27 kg: 600,000 U IM once (AHA guidelines 2009)
• Children weighing over 27 kg or greater: 1.2 million U IM once (AHA guidelines 2009)

Rheumatic Fever Prophylaxis

Adult dosage

• Acute attack: 1.2 million U IM monthly, or 600,000 U IM once every 2 weeks

Pediatric dosage

• Children weighing less than 27 kg: 600,000 U IM once every 4 weeks; high-risk patients once every 3 weeks (AHA guidelines 2009)
• Children weighing 27 kg or greater: 1.2 million U IM once every 4 weeks; high-risk patients once every 3 weeks (AHA guidelines 2009)

Syphilis

Adult dosage

• 2.4 million U IM x 1
• If pregnant: 2.4 million U IM once per week for two weeks, recommended
• If HIV+: 2.4 million U IM once per week for 3 weeks, recommend
• Early latent: 2.4 million U IM once
• Neurosyphilis: 2.4 million U IM once weekly for 3 weeks

Pediatric dosage

• Congenital (children younger than 2 years of age): 50,000 U/kg IM once
• Early: 50,000 U/kg IM once; not to exceed 2.4 million units/dose
• Less than 1 year duration: 50,000 U/kg once weekly for 3 weeks; not to exceed 2.5 million units/dose

Yaw, Bejel & Pinta

Adult dosage

• 1.2 million U IM once

Dosage Considerations – Should be Given as Follows: 

• See "Dosages."

Common side effects of Benzathine include:

• nausea, 
• vomiting, 
• diarrhea, 
• itching, 
• sweating, 
• allergic reaction, 
• flushing (sudden warmth, redness, or tingly feeling), 
• anxiety, 
• nervousness, 
• weakness, 
• tiredness, 
• headache, 
• dizziness, 
• drowsiness, 
• muscle or joint pain, and
• pain, swelling, bruising, or a hard lump where an injection was given 

Serious side effects of Benzathine include:

• hives, 
• difficult breathing, 
• swelling in the face or throat, 
• fever, 
• sore throat, 
• burning eyes, 
• skin pain, 
• red or purple skin rash with blistering and peeling, 
• pain, numbness, tingling, burning, or feeling cold, 
• pale or mottled skin, 
• blue-colored lips, fingers or toes, 
• severe pain in the legs, 
• tingling in the legs, 
• swelling in the lower leg, 
• weakness in the arms or legs, 
• blistering, peeling, discoloration, or painful skin changes where the medicine was injected, 
• severe stomach pain, 
• watery or bloody diarrhea (even if it occurs months after your last dose), 
• lightheadedness, 
• seizure, 
• pain, swelling, warmth, redness, bruising, bleeding, or a lump where the medicine was injected, 
• easy bruising, 
• unusual bleeding, 
• slow heart rate, 
• weak pulse, 
• fainting, 
• slow breathing, 
• pounding heartbeats, 
• fluttering in the chest, 
• confusion, 
• agitation, 
• hallucinations, 
• extreme fear, 
• pale or yellowed skin, 
• dark colored skin, 
• urination problems, 
• chills, 
• mouth sores, 
• warmth or redness under the skin, and
• vaginal itching or discharge

Rare side effects of Benzathine include:

• none 

This is not a complete list of side effects and other serious side effects or health problems may occur as a result of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider or pharmacist first.

• Benzathine has no noted severe interactions with any other drugs.
• Benzathine has no noted serious interactions with any other drugs. 
• Benzathine has no noted moderate interactions with any other drugs.
• Benzathine has no noted minor interactions with any other drugs.

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this drug, tell your doctor or pharmacist of all the drugs you use. Keep a list of all your medications with you, and share the list with your doctor and pharmacist. Check with your physician if you have health questions or concerns.

Contraindications

• Hypersensitivity; serious and occasionally fatal reactions have been reported

Effects of drug abuse

• None

Short-Term Effects

• See “What Are Side Effects Associated with Using Benzathine?”

Long-Term Effects

• See “What Are Side Effects Associated with Using Benzathine?”

Cautions

• For deep IM administration only; do not administer IV, SC, or IT
• Do not inject near nerve or artery
• Severe cutaneous adverse reactions (SCAR), such as Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS), and acute generalized exanthematous pustulosis (AGEP) reported in patients taking beta-lactam antibiotics; discontinue therapy when SCAR suspected; consider an alternative treatment
• Pseudomembranous colitis reported with antibacterial agents, including penicillin G
• Administer by deep intramuscular injection only in the upper, outer quadrant of buttock (dorsogluteal) or ventrogluteal site; quadriceps femoris fibrosis and atrophy reported following repeated intramuscular injections of penicillin preparations into anterolateral thigh and is not recommended

Pregnancy and Lactation

• Use may be acceptable during pregnancy. 
• Lactation: excreted into breast milk, caution advised.