Generic Name: Amoxicillin

  • What is Amoxicillin?

    Amoxicillin, an antibiotic, is used to treat a wide variety of bacterial infections, including gonorrhea, ear/nose/throat infections, skin infections, respiratory tract infections, and infections of the genital and urinary tract. In combination with other drugs, it is also used to treat duodenal ulcers caused by H. pylori bacteria.

  • What is the most important information I should know about Amoxicillin?

    If you are allergic to either penicillin or cephalosporin antibiotics in any form, consult your doctor before taking amoxicillin. There is a possibility that you are allergic to amoxicillin too; if a reaction occurs, it could be extremely severe. If you take the drug and feel signs of an allergic reaction, seek medical attention immediately.

    Amoxicillin will not treat a viral infection such as the common cold. It's important to take all of your medication as instructed by your doctor, even if you are feeling better in a few days. Not finishing the complete dose of amoxicillin may decrease the drug's effectiveness and increase the chances for bacterial resistance to amoxicillin and similar antibiotics.

    Diarrhea is a common problem caused by antibiotics, which usually ends when the antibiotic is discontinued. Sometimes after starting treatment with antibiotics, you can develop watery and bloody stools (with or without stomach cramps and fever), even as late as 2 or more months after having taken the last dose of the antibiotic. If this occurs, contact your doctor as soon as possible.

    The chewable tablet form of amoxicillin contains phenylalanine. If you or your child has the hereditary disease phenylketonuria, inform your doctor prior to taking amoxicillin chewable tablet.

  • Who should not take Amoxicillin?

    You should not use amoxicillin if you are allergic to penicillin or cephalosporin antibiotics.

  • What should I tell my doctor before I take the first dose of Amoxicillin?

    Tell your doctor about all prescription, over-the-counter, and herbal medications you are taking before beginning treatment with amoxicillin. Also, talk to your doctor about your complete medical history, especially if you have had asthma, hives, hay fever, or other allergies; diabetes; kidney or liver disease; mononucleosis (a viral illness commonly referred to as "mono" that results in weakness and fatigue for weeks or months); or phenylketonuria.

  • What is the usual dosage?

    The information below is based on the dosage guidelines your doctor uses. Depending on your condition and medical history, your doctor may prescribe a different regimen. Do not change the dosage or stop taking your medication without your doctor's approval.

    Ear, Nose, Throat, Skin, Genital, and Urinary Tract Infections

    Adults: For mild to moderate infections, the usual dose is 250 milligrams (mg) every 8 hours, or 500 mg every 12 hours. For severe infections, the usual dose is 500 mg every 8 hours, or 875 mg every 12 hours.

    Lower Respiratory Tract Infections

    Adults: The usual dose is 500 mg every 8 hours, or 875 mg every 12 hours.


    Adults: The usual dose is 3 grams as a single oral dose.


    Adults: For ulcer treatment, amoxicillin is combined with other medications. There are several dosage regimens available, and your doctor will choose the best one for you.

    Children >3 months: Children weighing ≥88 pounds should follow the recommended adult dosing schedule. Children weighing <88 pounds will have their dosage determined by their weight.

    Children ≤3 months: The maximum recommended dose is 30 mg per 2.2 pounds of body weight every 12 hours.

  • How should I take Amoxicillin?

    Amoxicillin can be taken with or without food. If you are using amoxicillin suspension, shake it well before using. If you are using amoxicillin chewable tablets, chew before swallowing.

    For children's dosages, the required amount of liquid medication should be placed directly on the child's tongue for swallowing. It can also be added to formula, milk, fruit juice, water, ginger ale, or cold drinks. The preparation should be taken immediately. To be certain the child is getting the full dose of medication, make sure he or she drinks the entire preparation.

  • What should I avoid while taking Amoxicillin?

    Do not stop taking amoxicillin, even if you're feeling better. Take amoxicillin exactly as prescribed by your doctor.

  • What are possible food and drug interactions associated with Amoxicillin?

    If amoxicillin is taken with certain other drugs, the effects of either could be increased, decreased, or altered. It is especially important to check with your doctor before combining amoxicillin with the following: chloramphenicol, estrogen, oral contraceptives, other antibiotics including erythromycin and tetracycline, probenecid, and sulfonamides such as sulfamethoxazole/trimethoprim.

  • What are the possible side effects of Amoxicillin?

    Side effects cannot be anticipated. If any develop or change in intensity, tell your doctor as soon as possible. Only your doctor can determine if it is safe for you to continue taking this drug.

    Side effects may include: agitation, anemia, anxiety, changes in behavior, colitis (inflammatory bowel disease), confusion, convulsions, diarrhea, dizziness, hives, hyperactivity, insomnia, liver problems and jaundice (yellowing of the eyes and skin), nausea, rash, vomiting

  • Can I receive Amoxicillin if I am pregnant or breastfeeding?

    The effects of amoxicillin during pregnancy are unknown. Amoxicillin should be used during pregnancy only when clearly needed. Amoxicillin may appear in breast milk. Tell your doctor immediately if you are pregnant, plan to become pregnant, or are breastfeeding.

  • What should I do if I miss a dose of Amoxicillin?

    If you miss a dose of amoxicillin, take the missed dose as soon as you remember it. However, if it is almost time for your next dose, skip the one you missed and return to your regular dosing schedule. Do not take two doses at once.

  • How should I store Amoxicillin?

    Amoxicillin suspension should be stored in a tightly closed bottle. Discard any unused medication after 14 days. Refrigeration is preferable. Store capsules, chewable tablets, and regular tablets at room temperature.

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