Amoxicillin

What is amoxicillin?               

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Amoxicillin is a penicillin antibiotic that fights bacteria.

Amoxicillin is used to treat many different types of infection caused by bacteria, such as tonsillitis, bronchitis, pneumonia, gonorrhea, and infections of the ear, nose, throat, skin, or urinary tract.               

Amoxicillin is also sometimes used 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).

There are many brands and forms of amoxicillin available and not all brands are listed on this leaflet.

Important information

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

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

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Amoxicillin can make birth control pills less effective. Ask your doctor about using a non-hormone method of birth control (such as a condom, diaphragm, spermicide) to prevent pregnancy while taking this medicine. Take this medication for the full prescribed length of time. Your symptoms may improve before the infection is completely cleared. Amoxicillin will not treat a viral infection such as the commoncold or flu. Do not share this medication with another person, even if they have the same symptoms you have.

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

Before taking this medicine

You should not use amoxicillin if you are allergic to any penicillin antibiotic, such as ampicillin, dicloxacillin, oxacillin, penicillin, or ticarcillin.

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

• asthma;
• liver or kidney disease;
• mononucleosis (also called "mono");
• a history of diarrhea caused by taking antibiotics; or
• food or drug allergies (especially to a cephalosporin antibiotic such as Omnicef, Cefzil, Ceftin, Keflex, and others).

If you are being treated for gonorrhea, your doctor may also have you tested for syphilis, another sexually transmitted disease.

Amoxicillin is not expected to harm an unborn baby. Tell your doctor if you are pregnant or plan to become pregnant during treatment.

Amoxicillin can make birth control pills less effective. Ask your doctor about using non hormonal birth control (condom, diaphragm with spermicide) to prevent pregnancy while taking this medicine.

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

The amoxicillin chewable tablet may contain phenylalanine. Talk to your doctor before using the chewable tablets if you have phenylketonuria (PKU).

How should I take amoxicillin?

Take amoxicillin exactly as prescribed by your doctor. Follow all directions on your prescription label. Do not take this medicine in larger or smaller amounts or for longer than recommended.

Take this medicine at the same time each day.

The Moxatag brand of amoxicillin should be taken with food, or within 1 hour after eating a meal.

Some forms of amoxicillin may be taken with or without food. Check your medicine label to see if you should take your medicine with food or not.

You may need to shake the liquid medicine well just before you measure a dose. Follow the directions on your medicine label.

Measure liquid medicine with the dosing syringe provided, or with a special dose-measuring spoon or medicine cup. If you do not have a dose-measuring device, ask your pharmacist for one. You may place the liquid directly on the tongue, or you may mix it with water, milk, baby formula, fruit juice, or ginger ale. Drink all of the mixture right away. Do not save any for later use.

The chewable tablet should be chewed before you swallow it.

Do not crush, chew, or break an extended-release tablet. Swallow it whole.

While using amoxicillin, you may need frequent blood tests. Your kidney and liver function may also need to be checked.

If you are taking amoxicillin with clarithromycin and/or lansoprazole to treat stomach ulcer, use all of your medications as directed. Read the medication guide or patient instructions provided with each medication. Do not change your doses or medication schedule without your doctor's advice.

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. Amoxicillin 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.

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

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

You may store liquid amoxicillin in a refrigerator but do not allow it to freeze. Throw away any liquid medicine that is not used within 14 days after it was mixed at the pharmacy.

What happens if I miss a dose?

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.

What happens if I overdose?

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

Overdose symptoms may include confusion, behavior changes, a severe skin rash, urinating less than usual, or seizure (black-out or convulsions).

What should I avoid while taking amoxicillin?

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

Amoxicillin side effects

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

Call your doctor at once if you have:

• diarrhea that is watery or bloody;
• fever, swollen gums, painful mouth sores, pain when swallowing, skin sores, cold or flu symptoms, cough, trouble breathing;
• swollen glands, rash or itching, joint pain, or general ill feeling;
• pale or yellowed skin, yellowing of the eyes, dark colored urine, fever, confusion or weakness;
• severe tingling, numbness, pain, muscle weakness;
• easy bruising, unusual bleeding (nose, mouth, vagina, or rectum), purple or red pinpoint spots under your skin; or
• severe skin reaction--fever, sore throat, swelling in your face or tongue, burning in your eyes, skin pain, followed by a red or purple skin rash that spreads (especially in the face or upper body) and causes blistering and peeling.

Common amoxicillin side effects may include:

• stomach pain, nausea, vomiting, diarrhea;
• vaginal itching or discharge;
• headache; or
• swollen, black, or "hairy" tongue.

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.

See also: Side effects (in more detail)

What other drugs will affect amoxicillin?

Other drugs may interact with amoxicillin, including prescription and over-the-counter medicines, vitamins, and herbal products. Tell each of your health care providers about all medicines you use now and any medicine you start or stop using.