Drug Information

Questions and Answers for Consumers 
on Penicillin G Procaine 

Penicillin G procaine is an antibiotic that is given by injection into a muscle. It is approved to treat bacterial infections in many different parts of the body. It does not work to treat viral infections, such as the common cold.

Penicillin G procaine is approved to treat anthrax in all its forms (inhaled (lung), skin, stomach and intestinal).

Another drug in the penicillin class carries a broad indication for illnesses caused by the anthrax organism (Bacillus anthracis). Because the most up-to-date information about appropriate dosing following exposure to anthrax is available for Cipro (ciprofloxacin), doxycycline, and penicillin G procaine, use of these three drugs has been recommended.

Antibiotic therapy should only be started in the case of suspected or confirmed exposure to anthrax. Antibiotics reduce the risk of severe disease following exposure, but do not prevent exposure.

4. What are some possible side effects of penicillin G procaine?

Some possible uncommon but serious side effects of penicillin G procaine include:

• A life-threatening allergic reaction (symptoms are difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; hives)

• a rare condition that has a number of symptoms, including severe agitation; anxiety; confusion; fear of impending death; feeling, hearing, or seeing things that are not real – many believe that this reaction is caused by the procaine ingredient of this product

• serious nerve damage or damage to the parts of the body that the affected blood vessels supply caused by accidental injection into arteries or veins very close to nerves – this side effect is more likely to happen in infants and children because they have less muscle mass protecting the nerves

• severe inflammation (swelling) of the colon
• unusual bleeding or bruising problems

Other more common, but less serious, side effects include:

• diarrhea

• pain at the injection site(s)

In deciding to use a medicine, the risks of taking the medicine must be weighed against the good it will do. If a person is exposed to anthrax, the risk of adverse events caused by penicillin treatment may be acceptable because of the seriousness of the disease. However, if a person is not exposed to anthrax, these risks may outweigh the benefits.

Some other things to consider:

• Using penicillin for more than 2 weeks may be associated with an increased risk of low white blood cell count and serum sickness. Serum sickness is a reaction similar to an allergy. However, unlike other allergies that occur very soon after receiving the medicine, serum sickness can develop 2 to 4 weeks later.

• There have been no formal clinical studies of the safety and effectiveness of penicillin in pregnant women. However, penicillins have been widely used in pregnant women and have not been shown to cause birth defects or other problems in animal studies.

• Before taking penicillin review with your health care provider ALL medications you are taking, including those that you take without a prescription.

There are online pharmacies from which you can confidently fill your prescriptions. Unfortunately, there are also questionable sites that make buying medicines online risky. Buying a medicine from an illegal Website puts you at risk. You may get a contaminated or fake product, the wrong product, an incorrect dose, or no product at all. Go to: http://www.fda.gov/oc/buyonline/default.htm for additional tips on buying medicines online.

FDA can not assure the quality or identity of products not approved for sale in the United States. Not all countries have the same approval procedures and manufacturing controls as the United States.

Possible risks include fake, unapproved, outdated, or sub-standard products. A document, entitled "Purchasing Medications Outside the United States", explains FDA’s concerns on this subject. This document can be found at: http://www.fda.gov/ora/import/purchasing_medications.htm.