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Medications and Drugs

Brand Names: Unasyn

Generic Name: ampicillin and sulbactam (Pronunciation: am pi SIL in and sul BAK tam)

What is ampicillin and sulbactam (Unasyn)?

Ampicillin and sulbactam are antibiotics in the penicillin group of drugs. They fight bacteria in your body.

The combination of ampicillin and sulbactam is used to treat many different types of infections caused by bacteria.

Ampicillin and sulbactam may also be used for other purposes not listed in this medication guide.

What are the possible side effects of ampicillin and sulbactam (Unasyn)?



Less serious side effects may include:

  • nausea, vomiting, stomach pain, bloating, gas;
  • vaginal itching or discharge;
  • headache;
  • itching;
  • swollen, black, or "hairy" tongue;
  • thrush (white patches or inside your mouth or throat); or
  • pain, swelling, or other irritation where the needle is placed.


What is the most important information I should know about ampicillin and sulbactam (Unasyn)?

Do not use this medication if you are allergic to ampicillin and sulbactam or to any other penicillin antibiotic, such as amoxicillin (Amoxil), carbenicillin (Geocillin), dicloxacillin (Dycill, Dynapen), oxacillin (Bactocill), penicillin (Beepen-VK, Ledercillin VK, Pen-V, Pen-Vee K, Pfizerpen, V-Cillin K, Veetids), and others.

Before using ampicillin and sulbactam, tell your doctor if you are allergic to cephalosporins such as Ceclor, Ceftin, Duricef, Keflex, and others, or if you have asthma, kidney disease, a bleeding or blood clotting disorder, mononucleosis (also called "mono"), or a history of any type of allergy.

Ampicillin and sulbactam can make birth control pills less effective, which may result in pregnancy. Before using ampicillin and sulbactam, tell your doctor if you use birth control pills.

Use this medication for the entire length of time prescribed by your doctor. Your symptoms may get better before the infection is completely treated. Ampicillin and sulbactam will not treat a viral infection such as the common cold or flu.



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