Amoxicillin

Generic Name: amoxicillin (am OX i sil in)
Brand names: Amoxil, Amoxil Pediatric Drops, Moxatag, Trimox, Wymox, Biomox, Amoxicot, Moxilin, Dispermox

What is amoxicillin?

Amoxicillin is an antibiotic in the penicillin group of drugs. It fights bacteria in your body.

Amoxicillin is used to treat many different types of infections caused by bacteria, such as ear infections, bladder infections, pneumonia, gonorrhea, and E. coli or salmonella infection. 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).

Amoxicillin may also be used for other purposes not listed in this medication guide.

What is the most important information I should know about amoxicillin?

Do not use this medication if you are allergic to amoxicillin or to any other penicillin antibiotic, such as ampicillin (Omnipen, Principen), 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 amoxicillin, tell your doctor if you are allergic to cephalosporins such as Ceclor, Ceftin, Duricef, 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.

Amoxicillin can make birth control pills less effective, which may result in pregnancy. Before taking amoxicillin, tell your doctor if you use birth control pills. Take this medication for the entire length of time prescribed by your doctor. Your symptoms may get better before the infection is completely treated. Amoxicillin will not treat a viral infection such as the common cold or flu. Do not give this medication to another person, even if they have the same symptoms you do.

Antibiotic medicines can cause diarrhea, which may be a sign of a new infection. If you have diarrhea that is watery or has blood in it, call your doctor. Do not use any medicine to stop the diarrhea unless your doctor has told you to.

What should I discuss with my healthcare provider before taking amoxicillin?

Do not use this medication if you are allergic to amoxicillin or to any other penicillin antibiotic, such as:

• ampicillin (Omnipen, Principen);

• carbenicillin (Geocillin);

• dicloxacillin (Dycill, Dynapen);

• oxacillin (Bactocill); or

• 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 any drugs (especially cephalosporins such as Ceclor, Ceftin, Duricef, Keflex, and others), or if you have:

• asthma;

• liver disease;

• kidney disease;

• a bleeding or blood clotting disorder;

• mononucleosis (also called "mono");

• a history of diarrhea caused by taking antibiotics; or

• a history of any type of allergy.

If you have any of these conditions, you may need a dose adjustment or special tests to safely take amoxicillin.

FDA pregnancy category B. This medication is not expected to be harmful to 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, which may result in pregnancy. Before taking amoxicillin, tell your doctor if you use birth control pills. Amoxicillin can pass into breast milk and may harm a nursing baby. Do not use this medication without telling your doctor if you are breast-feeding a baby.

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

How should I take amoxicillin?

Take this medication exactly as it was prescribed for you. Do not take the medication in larger amounts, or take it for longer than recommended by your doctor. Follow the directions on your prescription label.

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

You may take amoxicillin with or without food.

Shake the oral suspension (liquid) well just before you measure a dose. To be sure you get the correct dose, measure the liquid with a marked measuring spoon or medicine cup, not with a regular table spoon. 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 the pill whole. Breaking or opening the pill may cause too much of the drug to be released at one time.

To be sure this medication is helping your condition, your blood may need to be tested. Your kidney or liver function may also need to be tested. Do not miss any scheduled visits to your doctor.

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

Take this medication for the entire length of time prescribed by your doctor. Your symptoms may get better before the infection is completely treated. Amoxicillin will not treat a viral infection such as the common cold or flu. Do not give amoxicillin to another person, even if they have the same symptoms you do.

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

Store amoxicillin 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 amoxicillin 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. If it is almost time for your next dose, skip the missed dose and take the medicine at your next regularly scheduled time. Do not take extra medicine to make up the missed dose.

What happens if I overdose?

Seek emergency medical attention if you think you have used too much of this medicine.

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 has blood in it, call your doctor. Do not use any medicine to stop the diarrhea unless your doctor has told you to.

Amoxicillin side effects

Get emergency medical help if you have any of these signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat. Call your doctor at once if you have any of these serious side effects:

• fever, sore throat, and headache with a severe blistering, peeling, and red skin rash;

• nausea, stomach pain, low fever, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);

• diarrhea that is watery or bloody;

• fever, chills, body aches, flu symptoms;

• easy bruising or bleeding, unusual weakness;

• urinating less than usual or not at all;

• agitation, confusion, unusual thoughts or behavior; or

• seizure (black-out or convulsions).

Less serious side effects are more likely to occur, such as:

• nausea, vomiting, stomach pain;

• vaginal itching or discharge;

• headache;

• swollen, black, or "hairy" tongue; or

• thrush (white patches inside your mouth or throat).

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.

Amoxicillin Dosing Information

Usual Adult Dose for Actinomycosis:

500 mg orally 3 times a day or 875 mg orally twice a day for six months
Initial treatment of actinomycosis should include high dose parenteral penicillin G or ampicillin for 4 to 6 weeks, followed by appropriate oral therapy.

Usual Adult Dose for Anthrax Prophylaxis:

500 mg orally every 8 hours

Oral amoxicillin is not considered first-line treatment for anthrax prophylaxis; it may, however, be used to complete a 60-day prophylactic course after 10 to 14 days of ciprofloxacin or doxycycline in pregnant or lactating patients or in patients with contraindications to the other two agents. The total duration of antimicrobial therapy is 60 days.

Usual Adult Dose for Cutaneous Bacillus anthracis:

Treatment for confirmed cases of cutaneous Bacillus anthracis infection: 500 mg orally three times a day

Oral amoxicillin is not considered first-line treatment for the treatment of cutaneous anthrax; it may, however, be used to complete the treatment course once clinical response to ciprofloxacin or doxycycline has been observed or if the patient has contraindications to the other two agents. The total duration of antimicrobial therapy is 60 days.

Usual Adult Dose for Bacterial Endocarditis Prophylaxis:

2 g orally given one hour prior to the procedure

Amoxicillin is considered the standard agent for prophylaxis against bacterial endocarditis in at-risk individuals undergoing certain dental, oral, respiratory tract or esophageal procedures.

Amoxicillin is not appropriate as endocarditis prophylaxis for patients identified as high-risk, including those with prosthetic heart valves, prior endocarditis, and those who have had surgically constructed systemic shunts or conduits. These patients should receive appropriate parenteral antimicrobial therapy.

Usual Adult Dose for Chlamydia Infection:

500 mg orally 3 times a day for 7 days in pregnant patients as an alternative to erythromycin in macrolide-sensitive individuals

Amoxicillin does not have reliable activity against Chlamydia trachomatis.

Usual Adult Dose for Cystitis:

250 to 500 mg orally 3 times a day for 3 to 7 days; alternatively, 500 to 875 mg orally twice a day may be administered

Usual Adult Dose for Urinary Tract Infection:

250 to 500 mg orally 3 times a day for 3 to 7 days; alternatively, 500 to 875 mg orally twice a day may be administered

Usual Adult Dose for Helicobacter pylori Infection:

1 g orally 2 to 3 times a day for 14 days
Amoxicillin is used in combination with metronidazole and bismuth subsalicylate or with clarithromycin and a proton-pump inhibitor such as omeprazole or lansoprazole.

Usual Adult Dose for Lyme Disease -- Arthritis:

500 mg orally 3 times a day for 14 to 30 days
Early Lyme disease is often treated with an oral antibiotic such as doxycycline, cefuroxime or azithromycin, all of which are active against Borrelia burgdorferi. If amoxicillin is used, clinicians may wish to add probenecid, although the benefit of this addition is uncertain.

Up to 15% of patients with Lyme disease experience the Jarisch-Herxheimer reaction (increased fever, increased flushing rash, and increased pain) during the first 24 hours of therapy. This reaction is self-limiting, does not necessarily reflect true allergy to amoxicillin, and may be reduced in intensity by premedication with aspirin and/or prednisone.

Usual Adult Dose for Lyme Disease -- Carditis:

500 mg orally 3 times a day for 14 to 30 days
Early Lyme disease is often treated with an oral antibiotic such as doxycycline, cefuroxime or azithromycin, all of which are active against Borrelia burgdorferi. If amoxicillin is used, clinicians may wish to add probenecid, although the benefit of this addition is uncertain.

Up to 15% of patients with Lyme disease experience the Jarisch-Herxheimer reaction (increased fever, increased flushing rash, and increased pain) during the first 24 hours of therapy. This reaction is self-limiting, does not necessarily reflect true allergy to amoxicillin, and may be reduced in intensity by premedication with aspirin and/or prednisone.

Usual Adult Dose for Lyme Disease -- Erythema Chronicum Migrans:

500 mg orally 3 times a day for 14 to 30 days
Early Lyme disease is often treated with an oral antibiotic such as doxycycline, cefuroxime or azithromycin, all of which are active against Borrelia burgdorferi. If amoxicillin is used, clinicians may wish to add probenecid, although the benefit of this addition is uncertain.

Up to 15% of patients with Lyme disease experience the Jarisch-Herxheimer reaction (increased fever, increased flushing rash, and increased pain) during the first 24 hours of therapy. This reaction is self-limiting, does not necessarily reflect true allergy to amoxicillin, and may be reduced in intensity by premedication with aspirin and/or prednisone.

Usual Adult Dose for Lyme Disease -- Neurologic:

500 mg orally 3 times a day for 14 to 30 days
Early Lyme disease is often treated with an oral antibiotic such as doxycycline, cefuroxime or azithromycin, all of which are active against Borrelia burgdorferi. If amoxicillin is used, clinicians may wish to add probenecid, although the benefit of this addition is uncertain.

Up to 15% of patients with Lyme disease experience the Jarisch-Herxheimer reaction (increased fever, increased flushing rash, and increased pain) during the first 24 hours of therapy. This reaction is self-limiting, does not necessarily reflect true allergy to amoxicillin, and may be reduced in intensity by premedication with aspirin and/or prednisone.

Usual Adult Dose for Otitis Media:

250 to 500 mg orally 3 times a day for 10 to 14 days; alternatively, 500 to 875 mg orally twice a day may be administered

Usual Adult Dose for Pneumonia:

500 mg orally 3 times a day or 875 mg orally twice a day may be administered for 7 to 10 days if pneumococcal pneumonia is suspected
Only mild pneumonia due to pneumococcus should be treated with amoxicillin.

Usual Adult Dose for Sinusitis:

250 to 500 mg orally 3 times a day for 10 to 14 days; alternatively, 500 to 875 mg orally twice a day may be administered
Longer courses of therapy, up to 3 or 4 weeks, may be required in refractory or recurrent cases.

Usual Adult Dose for Skin or Soft Tissue Infection:

250 to 500 mg orally 3 times a day for 7 to 10 days; alternatively, 500 to 875 mg orally twice a day may be administered

Usual Adult Dose for Upper Respiratory Tract Infection:

250 to 500 mg orally 3 times a day for 7 to 10 days; alternatively, 500 to 875 mg orally twice a day may be administered

Usual Adult Dose for Bronchitis:

250 to 500 mg orally 3 times a day for 7 to 10 days; alternatively, 500 to 875 mg orally twice a day may be administered

Usual Adult Dose for Tonsillitis/Pharyngitis:

Immediate-release: 250 to 500 mg orally 3 times a day for 7 to 10 days; alternatively, 500 to 875 mg orally twice a day may be administered
Extended-release: 775 mg orally once a day within 1 hour after a meal for 10 days; for infections secondary to Streptococcus pyogenes

Usual Adult Dose for Bacterial Infection:

250 to 500 mg orally 3 times a day for 7 to 21 days; alternatively, 500 to 875 mg orally twice a day may be administered

Usual Pediatric Dose for Bacterial Endocarditis Prophylaxis:

50 mg/kg orally as a single dose 1 hour prior to procedure

Amoxicillin is not appropriate as endocarditis prophylaxis for patients identified as high-risk, including those with prosthetic heart valves, prior endocarditis, and those who have had surgically constructed systemic shunts or conduits. These patients should receive appropriate parenteral antimicrobial therapy.

Usual Pediatric Dose for Anthrax Prophylaxis:

80 mg/kg/day divided into equal doses administered orally every 8 hours
Maximum dose: 500 mg/dose

Oral amoxicillin is not considered first-line treatment for anthrax prophylaxis; it may, however, be used to complete a 60-day prophylactic course after 10 to 14 days of ciprofloxacin or doxycycline in pediatric patients. The total duration of antimicrobial therapy is 60 days.

Usual Pediatric Dose for Cutaneous Bacillus anthracis:

Treatment for confirmed cases of cutaneous Bacillus anthracis infection: 80 mg/kg/day divided into equal doses administered orally every 8 hours
Maximum dose: 500 mg/dose

Oral amoxicillin is not considered first-line treatment for the treatment of cutaneous anthrax; it may, however, be used to complete the treatment course once clinical response to ciprofloxacin or doxycycline has been observed. The total duration of antimicrobial therapy is 60 days.

Usual Pediatric Dose for Otitis Media:

4 weeks to 3 months: 20 to 30 mg/kg/day in divided doses every 12 hours
4 months to 12 years: 20 to 50 mg/kg/day in divided doses every 8 to 12 hours; acute otitis media due to highly resistant strains of Streptococcus pneumonia may require doses of 80 to 90 mg/kg/day orally divided into 2 equal doses 12 hours apart

Usual Pediatric Dose for Skin or Soft Tissue Infection:

4 weeks to 3 months: 20 to 30 mg/kg/day in divided doses every 12 hours
4 months to 12 years: 20 to 50 mg/kg/day in divided doses every 8 to 12 hours; acute otitis media due to highly resistant strains of Streptococcus pneumonia may require doses of 80 to 90 mg/kg/day orally divided into 2 equal doses 12 hours apart

Usual Pediatric Dose for Urinary Tract Infection:

4 weeks to 3 months: 20 to 30 mg/kg/day in divided doses every 12 hours
4 months to 12 years: 20 to 50 mg/kg/day in divided doses every 8 to 12 hours; acute otitis media due to highly resistant strains of Streptococcus pneumonia may require doses of 80 to 90 mg/kg/day orally divided into 2 equal doses 12 hours apart

Usual Pediatric Dose for Pneumonia:

40 to 50 mg/kg/day orally in divided doses every 8 hours

Usual Pediatric Dose for Tonsillitis/Pharyngitis:

4 weeks to 3 months: 20 to 30 mg/kg/day in divided doses every 12 hours
4 months to 12 years: 20 to 50 mg/kg/day in divided doses every 8 to 12 hour

12 years or older:
Immediate-release: 250 to 500 mg orally 3 times a day for 7 to 10 days; alternatively, 500 to 875 mg orally twice a day may be administered
Extended-release: 775 mg orally once a day within 1 hour after a meal for 10 days; for infections secondary to S pyogenes

What other drugs will affect amoxicillin?

Before taking amoxicillin, tell your doctor if you are using any of the following drugs:

• methotrexate (Rheumatrex, Trexall);

• probenecid (Benemid);

• a sulfa drug (such as Bactrim or Septra);

• an antibiotic such as azithromycin (Zithromax), clarithromycin (Biaxin), erythromycin (E.E.S., E-Mycin, Ery-Tab, Erythrocin), telithromycin (Ketek), or troleandomycin (Tao); or

• a tetracycline antibiotic such as demeclocycline (Declomycin), doxycycline (Adoxa, Doryx, Oracea, Vibramycin), minocycline (Dynacin, Minocin, Solodyn, Vectrin), or tetracycline (Brodspec, Panmycin, Sumycin, Tetracap).

This list is not complete and there may be other drugs that can interact with amoxicillin. Tell your doctor about all the prescription and over-the-counter medications you use. This includes vitamins, minerals, herbal products, and drugs prescribed by other doctors. Do not start using a new medication without telling your doctor.

Where can I get more information?

• Your pharmacist can provide more information about amoxicillin.

• Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Where can I buy amoxicillin?

You can buy amoxicillin by any brand name such as Amoxil at any reputable online pharmacy.