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Penicillins

Infectious Disease -ALL Agents (INDEX)

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Antimicrobials - Infectious Disease

Aminoglycosides Ansamycins/Rifamycins Antibiotics (Other)
Anti- Fungals Anti-Herpetic Agents Anti-Influenza Agents
Anti-Malarials Carbapenems Cephalosporins
Fluoroquinolones Glycopeptides HIV (anti) Agents
Lincosamides Lipopeptides Macrolides
Monobactams Oxazolidones Penicillins
Sulfonamide antibiotics Tetracyclines Tuberculosis (anti) agents

Ampicillin 

Use
Indicated in the treatment of infections caused by susceptible strains of the designated organisms in the following conditions:

Respiratory tract Infections caused by S. pneumoniae (formerly D. pneumoniae). Staphylococcus aureus (penicillinase and nonpenicillinase-producing), H. influenzae, and Group A beta-hemolytic Streptococci.

Bacterial Meningitis caused by E. coli, Group B Streptococci, and other Gram-negative bacteria (Listeria monocytogenes, N. meningitidis). The addition of an aminoglycoside with ampicillin may increase its effectiveness against Gram-negative bacteria.

Septicemia and Endocarditis caused by susceptible Gram-positive organisms including Streptococcus sp., penicillin G-susceptible staphylococci, and enterococci. Gram-negative sepsis caused by E. coli, Proteus mirabilis and Salmonella sp. respond to ampicillin. Endocarditis due to enterococcal strains usually respond to intravenous therapy. The addition of an aminoglycoside may enhance the effectiveness of ampicillin when treating streptoccoccal endocarditis.

Urinary Tract Infections caused by sensitve strains of E. coli and Proteus mirabilis.

Gastrointestinal Infections caused by Salmonella typhosa (typhoid fever), other Salmonella sp., and Shigella sp. (dysentery) usually respond to oral or intravenous therapy.

Bacteriology studies to determine the causative organisms and their susceptibility to ampicillin should be performed. Therapy may be instituted prior to obtaining results of susceptibility testing.

It is advisable to reserve the parenteral form of this drug for moderately severe and severe infections and for patients who are unable to take the oral forms. A change to oral ampicillin may be made as soon as appropriate.

To reduce the development of drug-resistant bacteria and maintain the effectiveness of Ampicillin for Injection, USP and other antibacterial drugs, Ampicillin for Injection, USP should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. When culture and susceptibility information are available, they should be considered in selecting or modifying antibacterial therapy. In the absence of such data, local epidemiology and susceptibility patterns may contribute to the empiric selection of therapy

Dosing:
 Infants and Children:
Mild-to-moderate infections:
I.M., I.V.: 100-150 mg/kg/day in divided doses every 6 hours (maximum: 2-4 g/day) .
Oral: 50-100 mg/kg/day in doses divided every 6 hours (maximum: 2-4 g/day) .
Severe infections/meningitis: I.M., I.V.: 200-400 mg/kg/day in divided doses every 6 hours (maximum: 6-12 g/day)

Endocarditis prophylaxis: I.M., I.V.:
Dental, oral, respiratory tract, or esophageal procedures: 50 mg/kg within 30 minutes prior to procedure in patients unable to take oral amoxicillin

Genitourinary and gastrointestinal tract (except esophageal) procedures:

High-risk patients: 50 mg/kg (maximum: 2 g) within 30 minutes prior to procedure, followed by ampicillin 25 mg/kg (or amoxicillin 25 mg/kg orally) 6 hours later; must be used in combination with gentamicin.

Moderate-risk patients: 50 mg/kg within 30 minutes prior to procedure
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Adults:
Susceptible infections:
Oral: 250-500 mg every 6 hours
I.M., I.V.: 250-500 mg every 6 hours

Sepsis/meningitis: I.M., I.V.: 150-250 mg/kg/24 hours divided every 3-4 hours (range: 6-12 g/day)

Endocarditis prophylaxis: I.M., I.V.:
Dental, oral, respiratory tract, or esophageal procedures: 2 g within 30 minutes prior to procedure in patients unable to take oral amoxicillin

Genitourinary and gastrointestinal tract (except esophageal) procedures:
High-risk patients: 2 g within 30 minutes prior to procedure, followed by ampicillin 1 g (or amoxicillin 1 g orally) 6 hours later; must be used in combination with gentamicin
Moderate-risk patients: 2 g within 30 minutes prior to procedure

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Renal Dosing:
[CRCL >50]: no change.
[30-49]: q6-8 hours.
[10-29]: q8-12 hours.
[<10 ]: q12-24 hours.Hemodialysis:
[<10 ml/min]: Give usual dose every 12-24 hours. Schedule dose after dialysis on dialysis days.

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Supplied:
Capsule (Principen®): 250 mg, 500 mg
Injection, powder for reconstitution, as sodium: 125 mg, 250 mg, 500 mg, 1 g, 2 g, 10 g
Powder for oral suspension (Principen®): 125 mg/5 mL (100 mL, 200 mL); 250 mg/5 mL (100 mL, 200 mL)

Ampicillin/ sulbactam (unasyn ®) 

Treatment of susceptible bacterial infections involved with skin and skin structure, intra-abdominal infections, gynecological infections; spectrum is that of ampicillin plus organisms producing beta-lactamases such as S. aureus , H. influenzae , E. coli , Klebsiella , Acinetobacter , Enterobacter , and anaerobes
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Dosing:
Children >/= 1 year: I.V.:
Mild-to-moderate infections: 100-150 mg ampicillin/kg/day (150-300 mg Unasyn®) divided every 6 hours; maximum: 8 g ampicillin/day (12 g Unasyn®)

Severe infections: 200-400 mg ampicillin/kg/day divided every 6 hours; maximum: 8 g ampicillin/day (12 g Unasyn®)

Adults: I.M., I.V.: 1-2 g ampicillin (1.5-3 g Unasyn®) every 6 hours; maximum: 8 g ampicillin/day (12 g Unasyn®)
-----------------------------

Renal Dosing
[CRCL >30]: 1.5-3.0 grams q6-8h
[15-30]: 1.5-3.0 grams q12h.
[5-14 ]: 1.5-3.0 grams q24 hours.
Hemodialysis: 1.5-3.0 grams q24 hours – give dose after dialysis when patient is being dialyzed.
PD: 1.5-3.0 grams q24 hours

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Supplied:
Injection, powder for reconstitution: 3 g [ampicillin sodium 2 g and sulbactam sodium 1 g]; 15 g [ampicillin sodium 10 g and sulbactam sodium 5 g] [bulk package]
Unasyn®: 1.5 g [ampicillin sodium 1 g and sulbactam sodium 0.5 g]; 3 g [ampicillin sodium 2 g and sulbactam sodium 1 g]; 15 g [ampicillin sodium 10 g and sulbactam sodium 5 g] [bulk package]

Amoxicillin 

Dosing:
Oral:
Children </= 3 months: 20-30 mg/kg/day divided every 12 hours.

Children: >3 months and <40 kg: Dosing range: 20-50 mg/kg/day in divided doses every 8-12 hours.

Ear, nose, throat, genitourinary tract, or skin/skin structure infections:

Mild to moderate: 25 mg/kg/day in divided doses every 12 hours or 20 mg/kg/day in divided doses every 8 hours

Severe: 45 mg/kg/day in divided doses every 12 hours or 40 mg/kg/day in divided doses every 8 hours

Acute otitis media due to highly-resistant strains of S. pneumoniae: Doses as high as 80-90 mg/kg/day divided every 12 hours have been used

Lower respiratory tract infections: 45 mg/kg/day in divided doses every 12 hours or 40 mg/kg/day in divided doses every 8 hours

Subacute bacterial endocarditis prophylaxis: 50 mg/kg 1 hour before procedure
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Adults: Dosing range: 250-500 mg every 8 hours or 500-875 mg twice daily; maximum dose: 2-3 g/day

Ear, nose, throat, genitourinary tract or skin/skin structure infections:
Mild to moderate: 500 mg every 12 hours or 250 mg every 8 hours.
Severe: 875 mg every 12 hours or 500 mg every 8 hours.
Lower respiratory tract infections: 875 mg every 12 hours or 500 mg every 8 hours.

Endocarditis prophylaxis: 2 g 1 hour before procedure.

Helicobacter pylori eradication: 1000 mg twice daily; requires combination therapy with at least one other antibiotic and an acid-suppressing agent (proton pump inhibitor or H2 blocker)
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Renal Dosing:
[CRCL >30 ]: No change.
[10-29 ml/min]: q8-12h. Do not use 875 mg tablet.
[<10 ml/min]: q24h. Do not use 875mg tablet.
Hemodialysis: 250-500mg q24h plus additional dose after dialysis.

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Supplied:
Capsule, as trihydrate: 250 mg, 500 mg
Tablet, as trihydrate [film coated] (Amoxil®): 500 mg, 875 mg
Tablet, chewable, as trihydrate: 125 mg, 200 mg, 250 mg, 400 mg

Powder for oral suspension, as trihydrate: 125 mg/5 mL (80 mL, 100 mL, 150 mL); 200 mg/5 mL (50 mL, 75 mL, 100 mL); 250 mg/5 mL (80 mL, 100 mL, 150 mL); 400 mg/5 mL (50 mL, 75 mL, 100 mL)

Powder for oral suspension, as trihydrate [drops] (Amoxil®): 50 mg/mL (15 mL [DSC], 30 mL) [bubble gum flavor]

Amoxicillin/ clavulanate (augmentin ®)

Dosing:
Children >/= 3 months and <40 kg:
Otitis media: 90 mg/kg/day divided every 12 hours for 10 days

Lower respiratory tract infections, severe infections, sinusitis: 45 mg/kg/day divided every 12 hours or 40 mg/kg/day divided every 8 hours.

Less severe infections: 25 mg/kg/day divided every 12 hours or 20 mg/kg/day divided every 8 hours
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Children >40 kg and Adults: 250-500 mg every 8 hours or 875 mg every 12 hours

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Children >/= 16 years and Adults:
Acute bacterial sinusitis: Extended release tablet: Two 1000 mg tablets every 12 hours for 10 days

CCommunity-acquired pneumonia: Extended release tablet: Two 1000 mg tablets every 12 hours for 7-10 days
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Renal Dosing:
[CRCL >30 ]: no change .
[10-30 ]: 250-500 mg q12h. Do not use the 875 mg tablet.
[<10 ml/min]: 250-500 mg q24h. Do not use the 875 mg tablet.
Hemodialysis: 250-500 mg q24h. Give additional dose after dialysis.

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Supplied:
Powder for oral suspension:
Augmentin®:
125: Amoxicillin 125 mg and clavulanate potassium 31.25 mg per 5 mL (75 mL, 100 mL, 150 mL) [banana flavor]
200: Amoxicillin 200 mg and clavulanate potassium 28.5 mg per 5 mL (50 mL, 75 mL, 100 mL) [contains phenylalanine 7 mg/5 mL; orange-raspberry flavor]
250: Amoxicillin 250 mg and clavulanate potassium 62.5 mg per 5 mL (75 mL, 100 mL, 150 mL) [orange flavor]
400: Amoxicillin 400 mg and clavulanate potassium 57 mg per 5 mL (50 mL, 75 mL, 100 mL) [contains phenylalanine 7 mg/5 mL; orange-raspberry flavor]
Augmentin ES-600®: Amoxicillin 600 mg and clavulanic potassium 42.9 mg per 5 mL (75 mL, 125 mL, 200 mL) [contains phenylalanine 7 mg/5 mL; orange flavor]

Tablet:
Augmentin®:
250: Amoxicillin trihydrate 250 mg and clavulanate potassium 125 mg
500: Amoxicillin trihydrate 500 mg and clavulanate potassium 125 mg
875: Amoxicillin trihydrate 875 mg and clavulanate potassium 125 mg

Tablet, chewable:
Augmentin®:
125: Amoxicillin trihydrate 125 mg and clavulanate potassium 31.25 mg
200: Amoxicillin trihydrate 200 mg and clavulanate potassium 28.5 mg
250: Amoxicillin trihydrate 250 mg and clavulanate potassium 62.5 mg
400: Amoxicillin trihydrate 400 mg and clavulanate potassium 57 mg

Tablet, extended release (Augmentin XR™): Amoxicillin 1000 mg and clavulanic acid 62.5 mg

Cloxacillin  (tegopen ®)

Microbiology
Penicillinase-resistant penicillins exert a bactericidal action against penicillin-susceptible microorganisms during the state of active multiplication. All penicillins inhibit the biosynthesis of the bacterial cell wall.

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Dosing:  (Should be taken 1 hour before or 2 hours after meals with water. )
Oral:
Children >1 month (<20 kg): 50-100 mg/kg/day in divided doses every 6 hours; up to a maximum of 4 g/day

Children (>20 kg) and Adults: 250-500 mg every 6 hours
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Renal Dosing:  No adjustments needed

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Supplied:
Capsule, as sodium: 250 mg, 500 mg

Powder for oral suspension, as sodium: 125 mg/5 mL (100 mL, 200 mL)

Dicloxacillin (dynapen ®) 

Microbiology
Penicillinase-resistant penicillins exert a bactericidal action against penicillin-susceptible microorganisms during the state of active multiplication. All penicillins inhibit the biosynthesis of the bacterial cell wall.
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Dosing:
Oral:
Use in newborns not recommended

Children <40 kg: 12.5-25 mg/kg/day divided every 6 hours; doses of 50-100 mg/kg/day in divided doses every 6 hours have been used for therapy of osteomyelitis

Children >40 kg and Adults: 125-250 mg every 6 hours
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Renal Dosing: No adjustments needed.
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Supplied:
Capsule: 250 mg, 500 mg

Nafcillin 

Microbiology
Penicillinase-resistant penicillins exert a bactericidal action against penicillin-susceptible microorganisms during the state of active multiplication. All penicillins inhibit the biosynthesis of the bacterial cell wall. The drugs in this class are highly resistant to inactivation by staphylococcal penicillinase and are active against penicillinase producing strains of Staphylococcus aureus. The penicillinase-resistant penicillins are active in vitro against a variety of other bacteria

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Dosing::
Children:
I.M.: 25 mg/kg twice daily

I.V.:
Mild to moderate infections: 50-100 mg/kg/day in divided doses every 6 hours
Severe infections: 100-200 mg/kg/day in divided doses every 4-6 hours
Maximum dose: 12 g/day

Adults:
I.M.: 500 mg every 4-6 hours
I.V.: 500-2000 mg every 4-6 hours
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Renal Dosing:  No adjustment in renal failure

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Supplied::
Infusion [premixed iso-osmotic dextrose solution]: 1 g (50 mL); 2 g (100 mL)
Injection, powder for reconstitution, as sodium: 1 g, 2 g, 10 g

Penicillin g 

Microbiology
Penicillin G is bactericidal against penicillin-susceptible microorganisms during the stage of active multiplication. It acts by inhibiting biosynthesis of cell-wall mucopeptide. It is not active against the penicillinase-producing bacteria, which include many strains of staphylococci. Penicillin G is highly active in vitro against staphylococci (except penicillinase-producing strains), streptococci (groups A, B, C, G, H, L and M), pneumococci and Neisseria meningitidis. Other organisms susceptible in vitro to penicillin G are Neisseria gonorrhoeae, Corynebacterium diphtheriae, Bacillus anthracis, clostridia, Actinomyces species, Spirillum minus, Streptobacillus monillformis, Listeria monocytogenes, and leptospira; Treponema pallidum is extremely susceptible.

Some species of gram-negative bacilli were previously considered susceptible to very high intravenous doses of penicillin G (up to 80 million units/day) including some strains of Escherichia coli, Proteus mirabilis, salmonella, shigella, Enterobacter aerogenes (formerly Aerobacter aerogenes) and Alcaligenes faecalis. Penicillin G is no longer considered a drug of choice for infections caused by these organisms

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Dosing:
I.M., I.V.:
Infants:
<7 days, <2000 g: 50,000 units/kg/day in divided doses every 12 hours
<7 days, >2000 g: 50,000 units/kg/day in divided doses every 8 hours
>7 days, <2000 g: 75,000 units/kg/day in divided doses every 8 hours
>7 days, >2000 g: 100,000 units/kg/day in divided doses every 6 hours
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Infants and Children (sodium salt is preferred in children): 100,000-250,000 units/kg/day in divided doses every 4 hours
Severe infections: Up to 400,000 units/kg/day in divided doses every 4 hours; maximum dose: 24 million units/day

Congenital syphilis:
Newborns: 50,000 units/kg/day I.V. every 8-12 hours for 10-14 days
Infants: 50,000 units/kg every 4-6 hours for 10-14 days

DDisseminated gonococcal infections or gonococcus ophthalmia (if organism proven sensitive): 100,000 units/kg/day in 2 equal doses (4 equal doses/day for infants >1 week)

Gonococcal meningitis: 150,000 units/kg in 2 equal doses (4 doses/day for infants >1 week)
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Adults: 2-24 million units/day in divided doses every 4 hours depending on sensitivity of the organism and severity of the infection

Neurosyphilis: 18-24 million units/day in divided doses every 3-4 hours for 10-14 days
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Renal Dosing:
[CRCL >50] Normal dose.
[10-50]: Give 75% of usual dose q4-6h.
[<10 ]: Give 20-50% of usual dose q4-6h.
Hemo: 500,000 - 800,000 units q6h or Give 20-50% of usual dose q4-6h.

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Supplied::

Infusion, as potassium [premixed iso-osmotic dextrose solution, frozen]: 1 million units (50 mL), 2 million units (50 mL), 3 million units (50 mL)

Injection, powder for reconstitution, as potassium (Pfizerpen®): 5 million units, 20 million units

Injection, powder for reconstitution, as sodium: 5 million units

Penicillin vk 

Dosing: Adults (Usual): 250-500mg po q6h.
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Dosing:
Oral:
Systemic infections:
Children <12 years: 25-50 mg/kg/day in divided doses every 6-8 hours; maximum dose: 3 g/day.
Children >/= 12 years and Adults: 125-500 mg every 6-8 hours.

Prophylaxis of pneumococcal infections:
Children <5 years: 125 mg twice daily.
Children >/= 5 years and Adults: 250 mg twice daily.

Prophylaxis of recurrent rheumatic fever:
Children <5 years: 125 mg twice daily
Children >/= 5 years and Adults: 250 mg twice daily
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Renal Dosing:
[CRCL > 10] no changes.
Dosing interval in renal impairment: Clcr<10 mL/minute: Administer 250 mg every 6 hours

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Supplied:
250 mg = 400,000 units
Powder for oral solution: 125 mg/5 mL (100 mL, 200 mL); 250 mg/5 mL (100 mL, 200 mL)

Tablet: 250 mg, 500 mg

Piperacillin (pipracil ®) 

Dosing:
Infants and Children: I.M., I.V.: 200-300 mg/kg/day in divided doses every 4-6 hours

Higher doses have been used in cystic fibrosis: 350-500 mg/kg/day in divided doses every 4-6 hours

Adults: I.M., I.V.:
Moderate infections (urinary tract infections): 2-3 g/dose every 6-12 hours; maximum: 2 g I.M./site

Serious infections: 3-4 g/dose every 4-6 hours; maximum: 24 g/24 hours

Uncomplicated gonorrhea: 2 g I.M. in a single dose accompanied by 1 g probenecid 30 minutes prior to injection
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Renal Dosing:
[>40 ml/min]: No changes.
[20-40]: 3-4 grams q8h.
[<20 ]: 4 grams q12h.
Hemo: Manufacturer: 2 grams IV q8h + 1 gram additional dose after each dialysis
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Supplied:
Injection, powder for reconstitution: 2 g, 3 g, 4 g, 40 g

Piperacillin/ tazobactam  (zosyn ®) 

Microbiology
Piperacillin sodium exerts bactericidal activity by inhibiting septum formation and cell wall synthesis of susceptible bacteria. In vitro, piperacillin is active against a variety of gram-positive and gram-negative aerobic and anaerobic bacteria. Tazobactam sodium has little clinically relevant in vitro activity against bacteria due to its reduced affinity to penicillin-binding proteins. It is, however, a β-lactamase inhibitor of the Richmond-Sykes class III (Bush class 2b & 2b') penicillinases and cephalosporinases. It varies in its ability to inhibit class II and IV (2a & 4) penicillinases. Tazobactam does not induce chromosomally-mediated β-lactamases at tazobactam concentrations achieved with the recommended dosage regimen.

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Dosing:
Children >12 years and Adults:

Nosocomial pneumonia: I.V.: Piperacillin/tazobactam 4/0.5 g every 6 hours for 7-14 days (when used empirically, combination with an aminoglycoside is recommended; consider discontinuation of aminoglycoside if P. aeruginosa is not isolated)

Severe infections: I.V.: Piperacillin/tazobactam 4/0.5 g every 8 hours or 3/0.375 g every 6 hours for 7-10 days

Moderate infections: I.M.: Piperacillin/tazobactam 2/0.25 g every 6-8 hours; treatment should be continued for >/= 7-10 days depending on severity of disease ( Note: I.M. route not FDA-approved)
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Renal Dosing:
[40-90 ml/min]: 3.375 grams q6h.
[20-40]: 2.25 gm q6h.
[<20]: 2.25 grams q8h.
Hemo: 2.25 grams q8h. Plus 0.75 g Zosyn should be administered following each dialysis period.
PD: 2.25 grams q8h.

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Supplied:
8:1 ratio of piperacillin sodium/tazobactam sodium:
Infusion [premixed iso-osmotic solution, frozen]:
2.25 g: Piperacillin 2 g and tazobactam 0.25 g (50 mL)
3.375 g: Piperacillin 3 g and tazobactam 0.375 g (50 mL)
4.5 g: Piperacillin 4 g and tazobactam 0.5 g (50 mL)

Injection, powder for reconstitution:
2.25 g: Piperacillin 2 g and tazobactam 0.25 g
3.375 g: Piperacillin 3 g and tazobactam 0.375 g
4.5 g: Piperacillin 4 g and tazobactam 0.5 g
40.5 g: Piperacillin 36 g and tazobactam 4.5 g

Ticarcillin 

Dosing:
Adults: I.M., I.V.: 1 to 4 g every 4 to 6 hours, usual dose: 3 g I.V. every 4 to 6 hours

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Renal Dosing:
[>60 ml/min]: No change.
[30-60]: 2 grams q4h.
[10-30]: 2 grams q8h.
[<10]: 1-2 grams q12h.
Hemo: 2 grams q12h + supplemental dose (2-3 grams) after dialysis.

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Supplied:
Injection, powder for reconstitution, as disodium: 3 g, 20 g

Ticarcillin/ clavulanate (timentin ®) 

Dosing:
I.V.:
Children and Adults <60 kg: 200-300 mg of ticarcillin component/kg/day in divided doses every 4-6 hours

Children >60 kg and Adults: 3.1 g (ticarcillin 3 g plus clavulanic acid 0.1 g) every 4-6 hours; maximum: 24 g/day

Urinary tract infections: 3.1 g every 6-8 hours
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Renal Dosing:
[>60 ml/min]: no change.
[30-60]: 2 gm q4h or 3.1gm q8h.
[10-30]: 2 gm q8h or 3.1 gm q12h.
[<10]: 2 grams q12h.
[<10 + hepatic dysfcn]: 2g q24h.
Hemo: 2 grams q12h + additional 3.1 g after each dialysis. PD: 3.1 grams q12h

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Supplied:
Infusion [premixed, frozen]: Ticarcillin disodium 3 g and clavulanate potassium 0.1 g (100 mL)

Injection, powder for reconstitution: Ticarcillin disodium 3 g and clavulanate potassium 0.1 g (3.1 g, 31 g)

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Reference(s)

National Institutes of Health, U.S. National Library of Medicine, DailyMed Database.
Provides access to the latest drug monographs submitted to the Food and Drug Administration (FDA). Please review the latest applicable package insert for additional information and possible updates.  A local search option of this data can be found here.

Penicillins

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