The combination of quinupristin and dalfopristin injection is used to prevent and treat certain serious skin infections. Quinupristin and dalfopristin are in a class of medications called streptogramin antibiotics. They work by killing bacteria that cause infections.

Antibiotics such as quinupristin and dalfopristin injection will not work for colds, flu, or other viral infections. Taking or using antibiotics when they are not needed increases your risk of getting an infection later that resists antibiotic treatment.

The combination of quinupristin and dalfopristin injection comes as a powder to be added to fluid and injected intravenously (into a vein). It is usually infused (injected slowly) over a period of 60 minutes once every 12 hours for at least 7 days. The length of your treatment depends on the type of infection you have and how your body responds to the medication. Your doctor will tell you how long to use quinupristin and dalfopristin injection.

You may receive quinupristin and dalfopristin injection in a hospital or you may use the medication at home. If you are using quinupristin and dalfopristin injection at home, use it at around the same times every day. Follow the directions on your prescription label carefully, and ask your doctor or other healthcare provider to explain any part you do not understand. Use quinupristin and dalfopristin injection exactly as directed. Do not infuse it more quickly than directed. Do not use more or less of it or use it more often than prescribed by your doctor.

If you will be using quinupristin and dalfopristin injection at home, your healthcare provider will show you how to infuse the medication. Be sure that you understand these directions, and ask your healthcare provider if you have any questions. Ask your healthcare provider what to do if you have any problems infusing quinupristin and dalfopristin injection.

You should begin feeling better during the first few days of your treatment with quinupristin and dalfopristin injection. If your symptoms do not improve, or if they get worse, call your doctor.

Use quinupristin and dalfopristin injection until you finish the prescription, even if you feel better. If you stop using quinupristin and dalfopristin injection too soon or skip doses, your infection may not be completely treated and the bacteria may become resistant to antibiotics.

Before using quinupristin and dalfopristin,

• tell your doctor and pharmacist if you are allergic to quinupristin and dalfopristin, other streptogramin antibiotics, any other medications, or any of the ingredients in quinupristin and dalfopristin 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 any of the following: carbamazepine (Carbatrol, Equetro, Tegretol, others), cyclosporine (Gengraf, Neoral, Sandimmune), diazepam (Diastat, Valium), diltiazem (Cardizem CD, Cartia XT, Diltzac, others), disopyramide (Norpace), docetaxel (Docefrez, Taxotere), lidocaine (Xylocaine), cholesterol-lowering medications (statins) such as lovastatin (Altoprev, in Advicor), medications for HIV such as delavirdine (Rescriptor), indinavir (Crixivan), nevirapine (Viramune), and ritonavir (Norvir, in Kaletra, in Viekira Pak, others); methylprednisolone (Medrol), midazolam, nifedipine (Adalat, Afeditab, Procardia), paclitaxel (Abraxane, Taxol), quinidine (in Nuedexta), tacrolimus (Astagraf, Envarsus XR, Prograf), verapamil (Calan, Isoptin), and vinblastine. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while using quinupristin and dalfopristin injection, call your doctor.

Infuse the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not infuse a double dose to make up for a missed one.

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

Symptoms of overdose may include:

• shortness of breath
• vomiting
• uncontrollable shaking of a part of the body
• lack of coordination

Your healthcare provider will tell you how to store your medication. Store your medication only as directed. Make sure you understand how to store your medication properly.

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

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

Quinupristin and dalfopristin injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• muscle or joint pain
• nausea
• diarrhea
• vomiting
• rash
• headache

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

• severe diarrhea with watery or bloody stools (up to 2 months after your treatment)
• pain, redness, and swelling at infusion site
• rash
• itching
• hives
• difficulty breathing or swallowing
• swelling of the face, eyes, mouth, throat, tongue, or lips

Quinupristin and dalfopristin 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 (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Keep all appointments with your doctor and the laboratory. Your doctor may order certain lab tests to check your body's response to quinupristin and dalfopristin injection.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.