Amoxicillin is a penicillin antibiotic that fights bacteria. It is used to treat many different types of infections caused by bacteria, such as tonsillitis, bronchitis, pneumonia, and infections of the ear, nose, throat, skin, or urinary tract. Additionally, it can be taken together with another antibiotic called clarithromycin (Biaxin) to treat stomach ulcers caused by Helicobacter pylori infection. This combination is sometimes used with a stomach acid reducer called lansoprazole (Prevacid).
Here are some important points about amoxicillin:

Warnings:

Do not use this medication if you are allergic to amoxicillin or any other penicillin antibiotic.
Inform your doctor if you are allergic to cephalosporins (such as Omnicef, Cefzil, Ceftin, Keflex) or have asthma, liver or kidney disease, bleeding or blood clotting disorder, mononucleosis (also called ?mono?), or any type of allergy.
Amoxicillin can make birth control pills less effective, so consult your doctor about using an alternative non-hormonal method of birth control while taking this medicine.
Take amoxicillin for the full prescribed length of time, even if your symptoms improve before the infection is completely cleared.
Amoxicillin will not treat viral infections like the common cold or flu.
Do not share this medication with others, even if they have similar symptoms.
Antibiotic medicines can cause diarrhea; if you experience watery or bloody diarrhea, stop taking amoxicillin and seek medical advice.