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What should I discuss with my healthcare provider before taking penicillin G potassium (Pfizerpen)?

You should not use 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.

To make sure you can safely use penicillin G potassium, tell your doctor if you have any of these other conditions:

• 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 potassium can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

How should I take penicillin G potassium (Pfizerpen)?

Penicillin G potassium is injected into a muscle or into a vein through an IV. You may be shown how to use an injection at home. Do not self-inject this medicine if you do not fully understand how to give the injection and properly dispose of used needles, IV tubing, and other items used to inject the medicine.

Penicillin G potassium may also be injected into the membrane surrounding the lungs, or into the fluid surrounding the spinal cord. The medicine must be given slowly through an IV infusion, and can take up to 24 hours to complete.

Prepare your dose in a syringe only when you are ready to give yourself an injection. Do not use the medication if it has changed colors or has particles in it. Call your doctor for a new prescription.

Use each disposable needle only one time. Throw away used needles in a puncture-proof container (ask your pharmacist where you can get one and how to dispose of it). Keep this container out of the reach of children and pets.

Use this medication for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Penicillin G potassium will not treat a viral infection such as the common cold or flu.

If you use this medication long-term, your blood may need to be tested to make sure the medicine is not causing harmful effects. Your kidney or liver function may also need to be tested. Visit your doctor regularly.

This medication can cause false results with certain lab tests for glucose (sugar) in the urine. Tell any doctor who treats you that you are using penicillin G potassium.

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

Store the powder at room temperature away from moisture and heat.

After mixing the powder with a diluent, store in the refrigerator and use it within 7 days. Do not freeze.

Penicillin G potassium that is supplied as a frozen solution should be stored in a deep freezer at a temperature of 4 degrees below 0 (F).

Thaw the solution either in a refrigerator or at room temperature. Do not heat the medicine to thaw it more quickly.

Penicillin G potassium that is thawed in the refrigerator should be used within 14 days. If you have thawed the medicine at room temperature, you must use it within 24 hours. Do not refreeze.

Once the solution has been thawed, it should look clear. Do not use the medicine if it looks cloudy or has particles in it, or if the medicine container leaks. Call your doctor or pharmacist for a new prescription.

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