Amoxicillin is used to treat bacterial infections in many different parts of the body. It is also used with other medicines (e.g., clarithromycin, lansoprazole) to treat H. pylori infection and duodenal ulcers.

Amoxicillin belongs to the group of medicines known as penicillin antibiotics. It works by killing the bacteria and preventing their growth. However, this medicine will not work for colds, flu, or other virus infections.

This medicine is available only with your doctor's prescription.

Take this medicine only as directed by your doctor. Do not take more of it, do not take it more often, and do not take it for a longer time than your doctor ordered.

You may take this medicine with or without food.

For patients using the oral liquid:

• Shake the bottle well before each use. Measure the dose with a marked measuring spoon, oral syringe, or medicine cup. The average household teaspoon may not hold the right amount of liquid.
• You may mix the oral liquid with a baby formula, milk, fruit juice, water, ginger ale, or another cold drink. Be sure the child drinks all of the mixture immediately.

Keep using this medicine for the full treatment time, even if you feel better after the first few doses. Your infection may not clear up if you stop using the medicine too soon.

Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.

Check with your doctor immediately if any of the following side effects occur:

Incidence not known

Abdominal or stomach cramps or tenderness

back, leg, or stomach pains

black, tarry stools

bleeding gums

blistering, peeling, or loosening of the skin

bloating

blood in the urine

bloody nose

chest pain

chills

clay-colored stools

cough

dark urine

diarrhea

diarrhea, watery and severe, which may also be bloody

difficulty with breathing

difficulty with swallowing

dizziness

fast heartbeat

feeling of discomfort

fever

general body swelling

headache

heavier menstrual periods

hives or welts

increased thirst

inflammation of the joints

itching

joint or muscle pain

loss of appetite

muscle aches

nausea or vomiting

nosebleeds

pain

pain in the lower back

pain or burning while urinating

painful or difficult urination

pale skin

pinpoint red spots on the skin

puffiness or swelling of the eyelids or around the eyes, face, lips, or tongue

rash

red, irritated eyes

redness, soreness, or itching skin

shortness of breath

sore throat

sores, ulcers, or white spots in the mouth or on the lips

sores, welting, or blisters

sudden decrease in the amount of urine

swollen, lymph glands

tenderness

tightness in the chest

unpleasant breath odor

unusual bleeding or bruising

unusual tiredness or weakness

unusual weight loss

vomiting of blood

watery or bloody diarrhea

wheezing

yellow eyes or skin

Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:

Less common

Bad, unusual, or unpleasant (after) taste

change in taste

Incidence not known

Agitation

black, hairy tongue

changes in behavior

confusion

convulsions

discoloration of the tooth (brown, yellow, or gray staining)

dizziness

sleeplessness

trouble with sleeping

unable to sleep

white patches in the mouth or throat or on the tongue

white patches with diaper rash

Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.

Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

If your or your child's symptoms do not improve within a few days, or if they become worse, check with your doctor.

This medicine may cause a serious allergic reaction called anaphylaxis. Anaphylaxis can be life-threatening and requires immediate medical attention. Call your doctor right away if you have a skin rash; itching; shortness of breath; trouble with breathing; trouble with swallowing; or any swelling of your hands, face, mouth, or throat after you or your child receive this medicine.

Amoxicillin may cause diarrhea, and in some cases it can be severe. It may occur 2 months or more after you stop taking this medicine. Do not take any medicine or give medicine to your child to treat diarrhea without first checking with your doctor. Diarrhea medicines may make the diarrhea worse or make it last longer. If you have any questions about this or if mild diarrhea continues or gets worse, check with your doctor.

Before you have any medical tests, tell the doctor in charge that you or your child are taking this medicine. The results of some tests may be affected by this medicine.

In some young patients, tooth discoloration may occur while using this medicine. The teeth may appear to have brown, yellow, or gray stains. To help prevent this, brush and floss your teeth regularly or have a dentist clean your teeth.

Birth control pills may not work while you are using this medicine. To keep from getting pregnant, use another form of birth control along with your birth control pills. Other forms include a condom, a diaphragm, or a contraceptive foam or jelly.

Do not take other medicines unless they have been discussed with your doctor. This includes prescription or nonprescription (over-the-counter [OTC]) medicines and herbal or vitamin supplements.