Dynapen is a penicillin antibiotic that fights bacteria in your body.

Dynapen is used to treat many different types of infections caused by bacteria such as bronchitis, pneumonia, or staphylococcal (also called "staph") infections.

Dynapen may also be used for purposes not listed in this medication guide.

Follow all directions on your medicine label and package. Tell each of your healthcare providers about all your medical conditions, allergies, and all medicines you use.

Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Take Dynapen on an empty stomach, at least 1 hour before or 2 hours after a meal.

Take this medicine with a full glass of water. To avoid heartburn or stomach irritation, do not take Dynapen while you are lying down or getting ready for bed.

While using Dynapen, you may need frequent medical tests.

This medicine can cause unusual results with certain medical tests. Tell any doctor who treats you that you are using Dynapen.

Use this medicine for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Skipping doses may also increase your risk of further infection that is resistant to antibiotics. Dynapen will not treat a viral infection such as the flu or a common cold.

Do not share this medicine with another person, even if they have the same symptoms you have.

Store at room temperature away from moisture, heat, and light.

You should not use Dynapen if you are allergic to Dynapen or to any other penicillin antibiotic, such as:

• amoxicillin;

• ampicillin;

• carbenicillin;

• oxacillin; or

• penicillin.

To make sure Dynapen is safe for you, tell your doctor if you have:

• asthma;

• a stomach illness (nausea, vomiting, digestive problems);

• liver disease;

• kidney disease;

• a bleeding or blood clotting disorder;

• a history of diarrhea caused by taking antibiotics; or

• a history of any type of allergy (especially cephalosporins such as Ceclor, Ceftin, Duricef, Keflex, and others).

It is not known whether this medicine will harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant.

Dynapen can make birth control pills less effective. Ask your doctor about using a non hormonal birth control (condom, diaphragm with spermicide) to prevent pregnancy.

Dicloxacillin can pass into breast milk and may harm a nursing baby. Tell your doctor if you are breast-feeding a baby.

Do not give this medicine to a child without medical advice.

Take the missed dose as soon as you remember. Skip the missed dose if it is almost time for your next scheduled dose. Do not take extra medicine to make up the missed dose.

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or bloody, call your doctor. Do not use anti-diarrhea medicine unless your doctor tells you to.

Get emergency medical help if you have signs of an allergic reaction: hives; difficult breathing; swelling of your face, lips, tongue, or throat.

Dynapen may cause serious side effects. Call your doctor at once if you have:

• severe stomach pain, diarrhea that is watery or bloody;

• nausea, vomiting;

• little or no urination;

• unusual bleeding or bruising;

• a seizure (convulsions);

• mouth pain or irritation, black tongue, sore throat; or

• fever, swollen glands, rash or itching, joint pain, or general ill feeling.

Common side effects of Dynapen may include:

• heartburn, nausea, vomiting, diarrhea;

• blisters or ulcers in your mouth, red or swollen gums, trouble swallowing; or

• abnormal liver function tests.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Tell your doctor about all your current medicines and any you start or stop using, especially:

• probenecid;

• tetracycline;

• a blood thinner (warfarin, Coumadin, Jantoven); or

• any other antibiotic.

This list is not complete. Other drugs may interact with dicloxacillin, including prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible interactions are listed in this medication guide.