Generic Name: penicillin g potassium (PEN-i-SIL-in G po-TAS-ee-um)
Brand Name: Pfizerpen
Pfizerpen is used for:
Treating some types of infections caused by certain bacteria.
Pfizerpen is a penicillin antibiotic. It works by interfering with the formation of the bacteria's cell wall while it is growing. This weakens the cell wall and kills the bacteria.
Do NOT use Pfizerpen if:
- you are allergic to any ingredient in Pfizerpen or to other penicillins
- you are taking a tetracycline antibiotic
Contact your doctor or health care provider right away if any of these apply to you.
Before using Pfizerpen:
Some medical conditions may interact with Pfizerpen. Tell your doctor or pharmacist if you have any medical conditions, especially if any of the following apply to you:
- if you are pregnant, planning to become pregnant, or are breast-feeding
- if you are taking any prescription or nonprescription medicine, herbal preparation, or dietary supplement
- if you have allergies to medicines, foods, or other substances
- if you have diarrhea or a stomach infection, especially in children 9 years old or younger
Some MEDICINES MAY INTERACT with Pfizerpen. Tell your health care provider if you are taking any other medicines, especially any of the following:
- Chloramphenicol, guar gum, or tetracycline antibiotics because they may decrease Pfizerpen's effectiveness
- Anticoagulants (eg, warfarin), heparin, or methotrexate because their actions and the risk of their side effects may be increased by Pfizerpen
- Aminoglycosides (eg, gentamicin), anticoagulants (eg, warfarin), chloramphenicol, oral contraceptives (birth control pills), or oral typhoid vaccine because their effectiveness may be decreased by Pfizerpen
This may not be a complete list of all interactions that may occur. Ask your health care provider if Pfizerpen may interact with other medicines that you take. Check with your health care provider before you start, stop, or change the dose of any medicine.
How to use Pfizerpen:
Use Pfizerpen as directed by your doctor. Check the label on the medicine for exact dosing instructions.
- Pfizerpen is usually given as an injection at your doctor's office, hospital, or clinic. If you will be using Pfizerpen at home, a health care provider will teach you how to use it. Be sure you understand how to use Pfizerpen. Follow the procedures you are taught when you use a dose. Contact your health care provider if you have any questions.
- Do not use Pfizerpen if it contains particles, is cloudy or discolored, or if the vial is cracked or damaged.
- Pfizerpen works best if it is given at the same time each day.
- Pfizerpen is injected into a muscle. Pfizerpen should not be injected into or near an artery or vein.
- To clear up your infection completely, use Pfizerpen for the full course of treatment. Keep using it even if you feel better in a few days.
- Keep this product, as well as syringes and needles, out of the reach of children and pets. Do not reuse needles, syringes, or other materials. Ask your health care provider how to dispose of these materials after use. Follow all local rules for disposal.
- If you miss a dose of Pfizerpen and you are using it regularly, use it as soon as possible. If it is almost time for the next dose, skip the missed dose and go back to your regular dosing schedule. Do not use 2 doses at once.
Ask your health care provider any questions you may have about how to use Pfizerpen.
Important safety information:
- Pfizerpen may cause drowsiness, dizziness, or blurred vision. These effects may be worse if you take it with alcohol or certain medicines. Use Pfizerpen with caution. Do not drive or perform other possibly unsafe tasks until you know how you react to it.
- Mild diarrhea is common with antibiotic use. However, a more serious form of diarrhea (pseudomembranous colitis) may rarely occur. This may develop while you use the antibiotic or within several months after you stop using it. Contact your doctor right away if stomach pain or cramps, severe diarrhea, or bloody stools occur. Do not treat diarrhea without first checking with your doctor.
- Be sure to use Pfizerpen for the full course of treatment. If you do not, the medicine may not clear up your infection completely. The bacteria could also become less sensitive to this or other medicines. This could make the infection harder to treat in the future.
- Pfizerpen only works against bacteria; it does not treat viral infections (eg, the common cold).
- Long-term or repeated use of Pfizerpen may cause a second infection. Tell your doctor if signs of a second infection occur. Your medicine may need to be changed to treat this.
- Diabetes patients - Pfizerpen may cause the results of some tests for urine glucose to be wrong. Ask your doctor before you change your diet or the dose of your diabetes medicine.
- Hormonal birth control (eg, birth control pills) may not work as well while you are using Pfizerpen. To prevent pregnancy, use an extra form of birth control (eg, condoms).
- Use Pfizerpen with caution in NEWBORNS; they may be more sensitive to its effects.
- PREGNANCY AND BREAST-FEEDING: If you become pregnant, contact your doctor. You will need to discuss the benefits and risks of using Pfizerpen while you are pregnant. Pfizerpen is found in breast milk. If you are or will be breast-feeding while you use Pfizerpen, contact your doctor. You will need to discuss the benefits and risks of using Pfizerpen while you are pregnant.
Possible side effects of Pfizerpen:
All medicines may cause side effects, but many people have no, or minor side effects. Check with your doctor if any of these most COMMON side effects persist or become bothersome:
Seek medical attention right away if any of these SEVERE side effects occur:
Black or hairy tongue; exaggerated reflexes; mild diarrhea; nausea or vomiting; pain, swelling, or redness at the injection site; twitching.
Severe allergic reactions (rash; hives; itching; difficulty breathing; tightness in the chest; swelling of the mouth, face, lips, or tongue); bizarre behavior; blood in stools or urine; changes in heartbeat; chest pain; chills; coma; convulsions; excessive sweating; extreme tiredness; fainting; fast heartbeat; fever; flushing with lightheadedness or fainting; hallucinations; itching; muscle pain; pale skin; pounding in the chest; rapid breathing; seizures; severe diarrhea; stomach pain/cramps; vaginal irritation or itching; vein swelling; worsening of skin lesions.
This is not a complete list of all side effects that may occur. If you have questions about side effects, contact your health care provider. Call your doctor for medical advice about side effects. To report side effects to the appropriate agency, please read the Guide to Reporting Problems to FDA.
If OVERDOSE is suspected:
Contact 1-800-222-1222 (the American Association of Poison Control Centers), your local poison control center, or emergency room immediately. Symptoms may include changes in heartbeat; coma; confusion; convulsions; diarrhea; excessive sweating; nausea; pale skin; vomiting.Proper storage of Pfizerpen:
The dry powder form of Pfizerpen may be stored below 86 degrees F (30 degrees C). Store away from heat, moisture, and light. Do not store in the bathroom. The mixed solution may be stored in the refrigerator for 1 week. Dispose of needles and syringes properly after use. Keep Pfizerpen, as well as needles, syringes, or other materials, out of the reach of children and away from pets.
- If you have any questions about Pfizerpen, please talk with your doctor, pharmacist, or other health care provider.
- Pfizerpen is to be used only by the patient for whom it is prescribed. Do not share it with other people.
- If your symptoms do not improve or if they become worse, check with your doctor.
- Check with your pharmacist about how to dispose of unused medicine.
This information should not be used to decide whether or not to take Pfizerpen or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about Pfizerpen. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to Pfizerpen. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using Pfizerpen.
Disclaimer: This information should not be used to decide whether or not to take this medicine or any other medicine. Only your health care provider has the knowledge and training to decide which medicines are right for you. This information does not endorse any medicine as safe, effective, or approved for treating any patient or health condition. This is only a brief summary of general information about this medicine. It does NOT include all information about the possible uses, directions, warnings, precautions, interactions, adverse effects, or risks that may apply to this medicine. This information is not specific medical advice and does not replace information you receive from your health care provider. You must talk with your healthcare provider for complete information about the risks and benefits of using this medicine.
More Pfizerpen resources
- Pfizerpen Concise Consumer Information (Cerner Multum)
- Pfizerpen Advanced Consumer (Micromedex) - Includes Dosage Information
- Pfizerpen Prescribing Information (FDA)
- penicillin G potassium Concise Consumer Information (Cerner Multum)
Compare Pfizerpen with other medications
- Anthrax Prophylaxis
- Aspiration Pneumonia
- Bacterial Infection
- Clostridial Infection
- Congenital Syphilis
- Cutaneous Bacillus anthracis
- Deep Neck Infection
- Fusospirochetosis, Trench Mouth
- Joint Infection
- Lyme Disease, Arthritis
- Lyme Disease, Carditis
- Lyme Disease, Erythema Chronicum Migrans
- Lyme Disease, Neurologic
- Meningitis, Meningococcal
- Meningitis, Pneumococcal
- Otitis Media
- Prevention of Perinatal Group B Streptococcal Disease
- Rat-bite Fever
- Rheumatic Fever Prophylaxis
- Skin Infection
- Strep Throat
- Syphilis, Early
- Syphilis, Latent
- Tertiary Syphilis
- Upper Respiratory Tract Infection