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amoxicillin (Rx)Brand and Other Names:Amoxil, Moxatag, more...Trimox

 
 
 

Dosing & Uses

AdultPediatric

Dosage Forms & Strengths

oral solution

  • 125mg/5mL
  • 200mg/5mL
  • 250mg/5mL
  • 400mg/5mL

capsule

  • 250mg
  • 500mg

tablet

  • 500mg
  • 875mg

tablet, chewable

  • 125mg
  • 250mg

extended-release (Moxatag)

  • 775mg
more...

Ear, Nose, & Throat Infections

Mild to moderate infections

  • 500 mg PO q12hr or 250 mg PO q8hr for 10-14 days

Severe infections

  • 875 mg PO q12hr or 500 mg PO q8hr for 10-14 days

Tonsillitis/pharyngitis

  • Moxatag: 775 mg PO qDay for 10 days, taken within 1 hour after finishing a meal

Spectrum of action

  • α- and β-hemolytic Strep, S pneumoniae, Staph spp, H influenzae

Genitourinary Tract Infections

Mild to moderate infections

  • 500 mg PO q12hr or 250 mg PO q8hr

Severe infections

  • 875 mg PO q12hr or 500 mg PO q8hr

Spectrum of action

  • E coli, P mirabilis, or E faecalis

Skin & Skin Structure Infections

Mild to moderate infections

  • 500 mg PO q12hr or 250 mg PO q8hr

Severe infections

  • 875 mg PO q12hr or 500 mg PO q8hr

Spectrum of action

  • α- and β-hemolytic Strep, Staph spp, E coli

Tonsilitis

775 mg (ER tabs) PO qDay for 10 days

Lower Respiratory Tract Infections

875 mg PO q12hr or 500 mg PO q8hr for 10-14 days

Spectrum of action

  • α- and β-hemolytic Strep, S pneumoniae, Staph spp, H influenzae

Helicobacter Pylori

H pylori infection and active or 1-year history of duodenal ulcer

Triple therapy

  • 1 g PO q12hr for 14 days with lansoprazole (30 mg) and clarithromycin (500 mg)

Dual therapy

  • 1 g PO q8hr for 14 days with lansoprazole (30 mg) in patients intolerant of, or resistant to, clarithromycin

Anthrax

Postexposure inhalational prophylaxis

500 mg PO q8hr

Infective Endocarditis

Prophylaxis

2 g PO 30-60 min before procedure

Dosing considerations

  • AHA guidelines recommend prophylaxis only in high-risk patients undergoing invasive procedures who have a history of cardiac conditions that predispose them to a risk of infection

Lyme Disease (Off-label)

Erythema migrans and other symptoms of early dissemination

500 mg PO q8hr (depending on size of patient) for 3-4wk

50 mg/kg/day q8hr in divided doses; maximum 500 mg/dose 

Chlamydial Infection in Pregnant Women (Off-label)

First trimester: 500 mg PO q8hr for 7 days

Dosing considerations

  • First trimester: Test to document chlamydial eradication and retest for infection 3 months after treatment
  • Second or third trimester: Test to document chlamydial eradication

Administration

Take without regard to meals

Dosing Modifications

Renal impairment: Patients with impaired renal function do not generally require dose reduction unless impairment is severe; do not administer extended-release product in patients with CrCl <30 mL/min

GFR <30 mL/min: Should not receive 875 mg (immediate release) or 775 mg (extended release)

GFR 10-30 mL/min: 250-500 mg q12hr, depending on severity of infection

GFR <10 mL/min: 250-500 mg q24hr depending on severity of infection

Hemodialysis patients: 250-500 mg q24hr, depending on severity of infection; patients should receive additional dose during and at completion of dialysis; do not administer extended-release product or 875 mg immediate release

Dosage Forms & Strengths

oral solution

  • 50mg/5mL
  • 125mg/5mL
  • 200mg/5mL
  • 250mg/5mL

capsule

  • 250mg
  • 500mg

tablet

  • 500mg
  • 875mg

tablet, chewable

  • 125mg
  • 250mg

tablet, extended release (Moxatag)

  • 775mg
more...

Ear, Nose, & Throat Infections

Mild to moderate infections

  • <3 months: ≤30 mg/kg/day PO divided q12hr for 48-72 hours; for ≥10 days for S pyogenes infections
  • >3 months and <40 kg: 25 mg/kg/day PO divided q12hr or 20 mg/kg/day PO divided q8hr 
  • >40 kg: 500 mg PO q12hr or 250 mg PO q8hr for 10-14 days

Severe infections

  • <3 months: ≤30 mg/kg/day PO divided q12hr for 48-72 hours; for ≥10 days for S pyogenes infections
  • >3 months and <40 kg: 45 mg/kg/day PO divided q12hr or 40 mg/kg/day PO divided q8hr  
  • >40 kg: 875 mg PO q12hr or 500 mg PO q8hr for 10-14 days

Tonsillitis/Streptococcal pharyngitis

  • 50 mg/kg PO qDay for 10 days, not to exceed 1 g/day, OR 25 mg/kg PO BID for 10 days, not to exceed 500 mg/dose 
  • >12 years: 775 mg (Moxatag) PO qDay for 10 days, taken within 1 hour after meal (swallow tablet whole; do not crush or chew)

Spectrum of action

  • α- and β-hemolytic Streptococcus, S pneumoniae, Staphylococcus, H influenzae

Acute Otitis Media

>3 months and <40kg: 80-90 mg/kg/day PO divided q8-12hr 

>40 kg: 500 mg PO q12hr or 250 mg PO q8hr for 10-14 days

Lower Respiratory Tract Infections

Mild, moderate, or severe infections

  • <3 months: ≤30 mg/kg/day PO divided q12hr for 48-72 hours; for ≥10 days for S pyogenes infections  
  • >3 months and <40 kg: 45 mg/kg/day PO divided q12hr or 40 mg/kg/day PO divided q8hr
  • >40kg: 875 mg PO q12hr or 500 mg PO q8hr for 10-14 days

Spectrum of action

  • α- and β-hemolytic Streptococcus, S pneumoniae, Staphylococcus, H influenzae

Anthrax

Postexposure inhalational prophylaxis

<40 kg: 15 mg/kg PO q8hr (minimum recommended dose; should not be <45 mg/kg/day or >q8hr 

>40 kg: 500 mg PO q8hr

80 mg/kg/day PO divided q8hr for 4 weeks (with concomitant vaccine) or for 60 days (without vaccine)

Infective Endocarditis

Prophylaxis

50 mg/kg PO 30-60 min before procedure 

Dosing considerations

  • AHA guidelines recommend prophylaxis only in high-risk patients undergoing invasive procedures with history of cardiac conditions that predispose them to infection

Lyme Disease

Erythema migrans and other symptoms of early dissemination

<3 months: Safety and efficacy not established

>3 months and 40 kg: 25-50 mg/kg/day divided q8hr; not to exceed 500 mg 

Administration

Take without regard to meals

Mixing oral suspension: Tap bottle until all powder flows freely; add approximately one third of the total amount of water for reconstitution and shake vigorously to wet powder; add remainder of water and shake vigorously again

After reconstitution, place required amount of suspension directly on child’s tongue for swallowing; if taste is unacceptable, required amount of suspension can be added to formula, milk, fruit juice, water, ginger ale, or other cold drinks; preparation must be taken immediately

Shake suspension well before using; any unused portion must be discarded after 14 days

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Interactions

Interaction Checker

amoxicillin and

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    Interactions Found

    Contraindicated

      Serious - Use Alternative

        Significant - Monitor Closely

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            Adverse Effects

            Frequency Not Defined

            Anaphylaxis

            Anemia

            AST/ALT elevation

            Mucocutaneous candidiasis

            Diarrhea

            Headache

            Nausea

            Vomiting

            Rash

            Pseudomembranous colitis

            Serum sickness-like reactions

            Postmarketing Reports

            Mucocutaneous candidiasis

            Gastrointestinal (eg, black hairy tongue and hemorrhagic/pseudomembranous colitis, which may occur during or after treatment)

            Hypersensitivity reactions (eg, anaphylaxis, serum sickness–like reactions, erythematous maculopapular rashes, erythema multiforme, Stevens-Johnson syndrome, exfoliative dermatitis, toxic epidermal necrolysis, acute generalized exanthematous pustulosis, hypersensitivity vasculitis, urticaria)

            Moderate increase in AST and/or ALT; hepatic dysfunction (eg, cholestatic jaundice, hepatic cholestasis and acute cytolytic hepatitis have been reported)

            Renal (eg, crystalluria)

            Anemia (eg, hemolytic anemia, thrombocytopenia, thrombocytopenic purpura, eosinophilia, leukopenia, agranulocytosis)

            CNS reactions (eg, reversible hyperactivity, agitation, anxiety, insomnia, confusion, convulsions, behavioral changes, dizziness)

            Tooth discoloration (brown, yellow, or gray staining); may be reduced or eliminated with brushing or dental cleaning

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            Warnings

            Contraindications

            Documented hypersensitivity to penicillins, cephalosporins, imipenem

            Cautions

            Anaphylaxis has been reported rarely but is more likely to occur following parenteral therapy with penicillins

            Clostridium difficile-associated diarrhea (CDAD) has been reported with use of nearly all antibacterial agents; severity may range from mild diarrhea to fatal colitis; CDAD may occur over 2 months after discontinuation of therapy; if CDAD is suspected or confirmed, discontinue immediately and begin appropriate fluid and electrolyte management, protein supplementation, antibiotic treatment of C difficile, and surgical evaluation

            Do not administer in patients with infectious mononucleosis because of risk of development of erythematous skin rash

            Do not administer to patients in the absence of a proven or suspected bacterial infection because of risk of development of drug-resistant bacteria

            Superinfections with bacterial or fungal pathogens may occur during therapy; if suspected, discontinue immediately and begin appropriate treatment

            Chewable tablets contain aspartame, which contains phenylalanine

            Use caution in patients with allergy to cephalosporins, carbapenems

            Endocarditis prophylaxis: use for only high-risk patients, as per recent AHA guidelines

            High doses may cause false urine glucose test by some methods

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            Pregnancy & Lactation

            Pregnancy category: B

            Lactation: Excreted in breast milk, use caution

            Pregnancy Categories

            A:Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.

            B:May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.

            C:Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.

            D:Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.

            X:Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.

            NA:Information not available.

            more...
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            Pharmacology

            Mechanism of Action

            Derivative of ampicillin and has similar antibacterial spectrum (certain gram-positive and gram-negative organisms); similar bactericidal action as penicillin; acts on susceptible bacteria during multiplication stage by inhibiting cell wall mucopeptide biosynthesis; superior bioavailability and stability to gastric acid and has broader spectrum of activity than penicillin; less active than penicillin against Streptococcus pneumococcus; penicillin-resistant strains also resistant to amoxicillin, but higher doses may be effective; more effective against gram-negative organisms (eg, N meningitidis, H influenzae) than penicillin

            Absorption

            Rapidly absorbed

            Bioavailability: 74-92%

            Peak plasma time: 2hr (capsule); 3.1 hr (extended release tab); 1 hr (suspension)

            Distribution

            Most body fluids and bone, CSF <1%

            Protein bound: 17-20%

            Metabolism

            Hepatic

            Elimination

            Excretion: Urine

            Half-life: 3.7 hr (full-term neonates); 1-2 hr (infants and children); 0.7-1.4 hr (adults)

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            Images

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            Formulary

            FormularyPatient Discounts

            To view formulary information first create a list of plans. Your list will be saved and can be edited at any time.

            Adding plans allows you to:

            • View the formulary and any restrictions for each plan.
            • Manage and view all your plans together – even plans in different states.
            • Compare formulary status to other drugs in the same class.
            • Access your plan list on any device – mobile or desktop.

            The above information is provided for general informational and educational purposes only. Individual plans may vary and formulary information changes. Contact the applicable plan provider for the most current information.

            Tier Description
            1 This drug is available at the lowest co-pay. Most commonly, these are generic drugs.
            2 This drug is available at a middle level co-pay. Most commonly, these are "preferred" (on formulary) brand drugs.
            3 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs.
            4 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            5 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            6 This drug is available at a higher level co-pay. Most commonly, these are "non-preferred" brand drugs or specialty prescription products.
            NC NOT COVERED – Drugs that are not covered by the plan.
            Code Definition
            PA Prior Authorization
            Drugs that require prior authorization. This restriction requires that specific clinical criteria be met prior to the approval of the prescription.
            QL Quantity Limits
            Drugs that have quantity limits associated with each prescription. This restriction typically limits the quantity of the drug that will be covered.
            ST Step Therapy
            Drugs that have step therapy associated with each prescription. This restriction typically requires that certain criteria be met prior to approval for the prescription.
            OR Other Restrictions
            Drugs that have restrictions other than prior authorization, quantity limits, and step therapy associated with each prescription.
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            Select a class to view formulary status for similar drugs

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