Amoxicillin

About Amoxicillin

Amoxicillin kills susceptible bacteria by blocking the building of their cell walls; like other antibiotics, it does not treat viral infections such as the common cold. The label covers ear, nose and throat, genitourinary, skin and lower respiratory infections caused by susceptible bacteria that do not make beta-lactamase, an enzyme that inactivates it. In adults with H. pylori infection and an active duodenal ulcer or one in the past year, it is taken for 14 days with clarithromycin and lansoprazole, or with lansoprazole alone when clarithromycin cannot be used or may not work. Adults and children over 40 kg usually take 500 mg every 12 hours or 250 mg every 8 hours, or 875 mg every 12 hours or 500 mg every 8 hours for severe or lower respiratory infections. Lighter children from 3 months are dosed by weight, and infants up to 12 weeks old take no more than 30 mg/kg a day. Streptococcus pyogenes infections are treated for at least 10 days to prevent rheumatic fever.

There is no boxed warning. Amoxicillin must not be taken after a serious allergic reaction, such as anaphylaxis or Stevens-Johnson syndrome, to it or another beta-lactam antibiotic (penicillins and cephalosporins). It can cause severe skin reactions (Stevens-Johnson syndrome, toxic epidermal necrolysis, DRESS and AGEP), so a rash is watched closely and amoxicillin is stopped if it progresses. Drug-induced enterocolitis syndrome, reported mostly in patients 18 or younger, causes prolonged vomiting 1 to 4 hours after a dose, sometimes with pallor, lethargy, low blood pressure, shock or diarrhea. Clostridioides difficile diarrhea can follow nearly any antibiotic, even more than two months later. Because many people with mononucleosis develop a rash on amoxicillin, the label says not to give it to them. Diarrhea, rash, vomiting and nausea are the most common side effects.

The pharmacy mixes the suspension when it is dispensed; a dose can go directly on a child’s tongue or into formula, milk, fruit juice, water, ginger ale or another cold drink, taken at once. The label says amoxicillin may make combined estrogen and progestin birth control pills less effective, and that penicillins pass into breast milk and may sensitize a nursing infant. With a glomerular filtration rate under 30 mL/min, the 875 mg tablet is not used and doses are spaced further apart. Amoxicillin with clavulanate is a different medicine, and H. pylori products that combine amoxicillin with other drugs (Talicia, and the Voquezna Dual Pak and Triple Pak) are separate products.

Taking Amoxicillin

How to take it

Every 8 or 12 hours as prescribed; the label says to take it at the start of a meal to lessen stomach upset. Chew chewable tablets completely before swallowing. Shake the suspension well and measure each dose with a marked oral syringe or medicine spoon. Finish the prescription even if you feel better; skipping doses or stopping early can make the treatment less effective and make bacteria resistant.

If you miss a dose

Take it as soon as you remember, unless it is almost time for the next dose; then skip the missed dose and carry on as usual. Do not take a double dose.

Storage

Capsules, tablets and unmixed powder at room temperature, away from excess heat and moisture, out of reach of children. The mixed suspension is preferably refrigerated but may be kept at room temperature; do not freeze it, and throw away any left after 14 days.

Interactions to know about

Probenecid raises amoxicillin levels, allopurinol makes rashes more likely, and the INR can rise with warfarin or other oral anticoagulants. Chloramphenicol, macrolides, sulfonamides and tetracyclines may interfere with its action. It can cause false-positive results on some urine glucose tests.

This summarizes the official prescribing information. Your prescriber’s and pharmacist’s instructions, and the leaflet that comes with your medicine, take priority.

Why the cash price for Amoxicillin differs from pharmacy to pharmacy

Every form of amoxicillin is sold as a generic, so quotes for the same course differ by each pharmacy’s fee and markup and by whether amoxicillin is on its flat-price generic list. A pharmacist fills the form and strength written; capsules, tablets, chewable tablets and the suspension are not swapped without the prescriber.

The suspension is quoted by strength and bottle size. A child’s dose is set by weight, so the amount the full course needs shapes the quote.

Ways to pay less for Amoxicillin without insurance

• Ask whether amoxicillin is on the pharmacy’s flat-price generic list, and compare more than one pharmacy.
• For a child’s suspension, ask how many bottles the full course needs, so the quote covers all of it.
• If a child can swallow capsules or chew tablets, ask the prescriber whether a solid form would suit.
• If the prescription names Amoxil, ask whether it allows a generic to be dispensed.
• Upload the prescription to Script Unlock so licensed pharmacies can quote their cash price. You pay the pharmacy directly.

Questions to ask your pharmacist about Amoxicillin

1. 1.Should I take it at the start of a meal?
2. 2.How do I measure and store my child’s liquid?
3. 3.Which rash, swelling or breathing problem means I should stop it and get help?
4. 4.Does it interact with my birth control pills, warfarin or allopurinol?

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