Pfizerpen A-S

Name: Pfizerpen A-S

How should this medicine be used?

Penicillin G procaine injection comes as a suspension (liquid) in a prefilled syringe to inject into the muscles of the buttocks or thigh by a doctor or nurse in a medical facility. It is usually given once a day. The length of your treatment depends on the type of infection that you have and how well you respond to the medication.

You should begin to feel better during the first few days of treatment with penicillin G procaine injection. If your symptoms do not improve or get worse, call your doctor.

Be sure to keep all appointments to receive penicillin G procaine injection on schedule even if you feel better. If you stop receiving penicillin G procaine injection too soon or skip doses, your infection may not be completely treated and the bacteria may become resistant to antibiotics.

You may experience a sudden severe reaction immediately after receiving a dose of penicillin G procaine injection that may last for approximately 15 to 30 minutes. Tell your doctor if you experience any of the following symptoms right after your injection: anxiety, confusion, agitation, depression, weakness, seizures, seeing things or hearing voices that do not exist, aggressive behavior, and fear of dying.

What special precautions should I follow?

Before receiving penicillin G procaine injection,

  • tell your doctor and pharmacist if you are allergic to penicillin G procaine injection, penicillin antibiotics; cephalosporin antibiotics such as cefaclor, cefadroxil, cefazolin (Ancef, Kefzol), cefditoren (Spectracef), cefepime (Maxipime), cefixime (Suprax), cefotaxime (Claforan), cefoxitin, cefpodoxime, cefprozil, ceftazidime (Fortaz, Tazicef), ceftibuten (Cedax), ceftriaxone (Rocephin), cefuroxime (Ceftin, Zinacef), and cephalexin (Keflex); procaine; or any other medications. Ask your doctor or pharmacist if you are not sure if a medication you are allergic to belongs to one of these groups of medications. Also tell your doctor if you are allergic to any of the ingredients in penicillin G procaine injection. Ask your pharmacist for a list of the ingredients.
  • tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Be sure to mention: probenecid (Probalan) and tetracycline (Achromycin). Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
  • tell your doctor if you have or have ever had asthma, allergies, hay fever, hives, or kidney disease.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. If you become pregnant while receiving penicillin G procaine injection, call your doctor.

What special dietary instructions should I follow?

Unless your doctor tells you otherwise, continue your normal diet.

What should I do if I forget a dose?

If you miss an appointment to receive penicillin G procaine injection, call your doctor as soon as possible.

What side effects can this medication cause?

Penicillin G procaine injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • nausea
  • vomiting
  • pain, swelling, lump, bleeding, or bruising in the area where the medication was injected

Some side effects can be serious. If you experience any of these symptoms, call your doctor immediately or get emergency medical treatment:

  • rash
  • hives
  • itching
  • difficulty breathing or swallowing
  • swelling of the face, throat, tongue, lips, eyes, hands, feet, ankles, or lower legs
  • hoarseness
  • sore throat
  • chills
  • fever
  • headache
  • muscle or joint pain
  • weakness
  • fast heartbeat
  • severe diarrhea (watery or bloody stools) with or without fever and stomach cramps that may occur up to 2 months or more after your treatment
  • sudden onset of lower back pain, muscle weakness, numbness, and tingling
  • blue or black skin discoloration in the area where the medication was injected
  • skin blistering, peeling, or shedding in the area where the medication was injected
  • numbness of the arms or legs in the area where the medication was injected

Penicillin G procaine injection may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online ( or by phone (1-800-332-1088).

Other names

  • APPG
  • Benzylpenicillin Procaine
  • Procaine Penicillin G