Medicines Containing Amoxicillin

Amoksisilin (Amoxicillin

Bactericidal aminopenicillin w/same spectrum as ampicillin (ineffective against bacteria that produce beta-lactamase)

Most likely adverse effects are GI-related, but hypersensitivity and other adverse effects rarely occur

Available in oral and parenteral dosage forms in USA

Pharmacology/Uses/Indications

Although there may be some slight differences in activity against certain organisms, amoxicillin generally shares the same spectrum of activity and uses as ampicillin. Because it is better absorbed orally (in non-ruminants), higher serum levels may be attained than with ampicillin.

Penicillins are usually bactericidal against susceptible bacteria and act by inhibiting mucopeptide synthesis in the cell wall resulting in a defective barrier and an osmotically unstable spheroplast. The exact mechanism for this effect has not been definitively determined, but betalactam antibiotics have been shown to bind to several enzymes (carboxypeptidases, transpeptidases, endopeptidases) within the bacterial cytoplasmic membrane that are involved with cell wall synthesis. The different affinities that various beta-lactam antibiotics have for these enzymes (also known as penicillin-binding proteins; PBPs) help explain the differences in spectrums of activity the drugs have that are not explained by the influence of beta-lactamases. Like other beta-lactam antibiotics, penicillins are generally considered to be more effective against actively growing bacteria.

The aminopenicillins, also called the “broad-spectrum” or ampicillin penicillins, have increased activity against many strains of Gram negative aerobes not covered by either the natural penicillins or penicillinase-resistant penicillins, including some strains of E. coli, Klebsiella, and Haemophilus. Like the natural penicillins, they are susceptible to inactivation by beta-lactamaseproducing bacteria (e.g. Staph aureus). Although not as active as the natural penicillins, they do have activity against many anaerobic bacteria, including Clostridial organisms. Organisms that are generally not susceptible include Pseudomonas aeruginosa, Serratia, Indole-positive Proteus (Proteus mirabilis is susceptible), Enterobacter, Citrobacter, and Acinetobacter. The aminopenicillins also are inactive against Rickettsia, mycobacteria, fungi, Mycoplasma, and viruses.

In order to reduce the inactivation of penicillins by beta-lactamases, potassium clavulanate and sulbactam have been developed to inactivate these enzymes and thus extend the spectrum of those penicillins. When used with a penicillin, these combinations are often effective against many beta-lactamase-producing strains of otherwise resistant E. coli, Pasturella spp, Staphylococcus spp, Klebsiella, and Proteus. Type I beta-lactamases that are often associated with E. coli, Enterobacter, and Pseudomonas are not generally inhibited by clavulanic acid.

Uses/Indications

The aminopenicillins have been used for a wide range of infections in various species. FDA-approved indications/species, as well as non-approved uses, are listed in the Dosages section below.

Pharmacokinetics (General)

The oral absorption characteristics of the penicillins are dependent upon its class. Penicillin G is the only available oral penicillin that is substantially affected by gastric pH and can be completely inactivated at pH’s of less than 2. The other orally available penicillins are resistant to acid degradation but bioavailability can be decreased by the presence of food (not amoxicillin). Of the orally administered penicillins, penicillin V and amoxicillin tend to have the greatest bioavailability in their respective classes.

Penicillins are generally distributed widely throughout the body. Most drugs attain therapeutic levels in the kidneys, liver, heart, skin, lungs, intestines, bile, bone, prostate, and peritoneal, pleural and synovial fluids. Penetration into the CSF and eye only occur with inflammation and may not reach therapeutic levels. Penicillins are bound in varying degrees to plasma proteins and they cross the placenta.

Most penicillins are rapidly excreted largely unchanged by the kidneys into the urine via glomerular filtration and tubular secretion. Probenecid can prolong half-lives and increase serum levels by blocking the tubular secretion of penicillins. Except for nafcillin and oxacillin, hepatic inactivation and biliary secretion is a minor route of excretion.

Pharmacokinetics (specific)

Amoxicillin trihydrate is relatively stable in the presence of gastric acid. After oral administration, it is about 74-92% absorbed in humans and animals (monogastric). Food will decrease the rate, but not the extent of oral absorption and many clinicians suggest giving the drug with food, particularly if there is concomitant associated GI distress. Amoxicillin serum levels will generally be 1.5-3 times greater than those of ampicillin after equivalent oral doses.

After absorption the volume of distribution for amoxicillin is approximately 0.3 L/kg in humans and 0.2 L/kg in dogs. The drug is widely distributed to many tissues, including liver, lungs, prostate (human), muscle, bile, and ascitic, pleural and synovial fluids. Amoxicillin will cross into the CSF when meninges are inflamed in concentrations that may range from 10-60% of those found in serum. Very low levels of the drug are found in the aqueous humor, and low levels found in tears, sweat and saliva. Amoxicillin crosses the placenta, but it is thought to be relatively safe to use during pregnancy. It is approximately 17-20% bound to human plasma proteins, primarily albumin. Protein binding in dogs is approximately 13%. Milk levels of amoxicillin are considered to be low.

Amoxicillin is eliminated primarily through renal mechanisms, principally by tubular secretion, but some of the drug is metabolized by hydrolysis to penicilloic acids (inactive) and then excreted in the urine. Elimination half-lives of amoxicillin have been reported as 45-90 minutes in dogs and cats, and 90 minutes in cattle. Clearance is reportedly 1.9 ml/kg/min in dogs.

Contraindications/Precautions/Reproductive Safety

Penicillins are contraindicated in patients who have a history of hypersensitivity to them. Because there may be cross-reactivity, use penicillins cautiously in patients who are documented hypersensitive to other beta-lactam antibiotics (e.g., cephalosporins, cefamycins, carbapenems).

Do not administer systemic antibiotics orally in patients with septicemia, shock, or other grave illnesses as absorption of the medication from the GI tract may be significantly delayed or diminished. Parenteral (preferably IV) routes should be used for these cases.

Penicillins have been shown to cross the placenta and safe use of them during pregnancy has not been firmly established, but neither have there been any documented teratogenic problems associated with these drugs. However, use only when the potential benefits outweigh the risks.

Adverse Effects/Warnings

Adverse effects with the penicillins are usually not serious and have a relatively low frequency of occurrence.

Hypersensitivity reactions unrelated to dose can occur with these agents and can be manifested as rashes, fever, eosinophilia, neutropenia, agranulocytosis, thrombocytopenia, leukopenia, anemias, lymphadenopathy, or full blown anaphylaxis. In humans, it is estimated that up to 15% of patients hypersensitive to cephalosporins will also be hypersensitive to penicillins. The incidence of cross-reactivity in veterinary patients is unknown.

When given orally, penicillins may cause GI effects (anorexia, vomiting, diarrhea). Because the penicillins may also alter gut flora, antibiotic-associated diarrhea can occur, as well as selecting out resistant bacteria maintaining residence in the colon of the animal (superinfections).

High doses or very prolonged use has been associated with neurotoxicity (e.g., ataxia in dogs). Although the penicillins are not considered to be hepatotoxic, elevated liver enzymes have been reported. Other effects reported in dogs include tachypnea, dyspnea, edema and tachycardia.

Overdosage/Acute Toxicity

Acute oral penicillin overdoses are unlikely to cause significant problems other than GI distress, but other effects are possible (see Adverse effects). In humans, very high dosages of parenteral penicillins, especially in patients with renal disease, have induced CNS effects.

Drug Interactions

In vitro studies have demonstrated that penicillins can have synergistic or additive activity against certain bacteria when used with aminoglycosides or cephalosporins.

Use of bacteriostatic antibiotics (e.g., chloramphenicol, erythromycin, tetracyclines) with penicillins is generally not recommended, particularly in acute infections where the organism is proliferating rapidly as penicillins tend to perform better on actively growing bacteria. In low concentrations, certain penicillins (e.g., ampicillin, oxacillin or nafcillin) may have additive or synergistic effects against certain bacteria when used with rifampin, but there is apparent antagonism when the penicillin is present in high concentrations.

Probenecid competitively blocks the tubular secretion of most penicillins, thereby increasing serum levels and serum half-lives.

Drug/Laboratory Interactions

Ampicillin/amoxicillin may cause false-positive urine glucose determinations when using cupric sulfate solution (Benedict’s Solution, Clinitest®). Tests utilizing glucose oxidase (Tes-Tape®, Clinistix®) are not affected by ampicillin/amoxicillin.

In humans, clavulanic acid and high dosages of piperacillin have caused a false-positive direct Combs’ test.

As penicillins and other beta-lactams can inactivate aminoglycosides in vitro (and in vivo in patients in renal failure), serum concentrations of aminoglycosides may be falsely decreased if the patient is also receiving beta-lactam antibiotics and the serum is stored prior to analysis. It is recommended that if the assay is delayed, samples be frozen and, if possible, drawn at times when the beta-lactam antibiotic is at a trough.

Monitoring Parameters

Because penicillins usually have minimal toxicity associated with their use, monitoring for efficacy is usually all that is required unless toxic signs or symptoms develop. Serum levels and therapeutic drug monitoring are not routinely done with these agents.

Doses

Dogs:

For susceptible infections:

a) For Gram + infections: 10 mg/kg PO, IM, SC twice daily for at least 2 days after symptoms subside.

For Gram – infections: 20 mg/kg PO three times daily or IM, SC twice daily; for at least 2 days after symptoms subside. (Aucoin 2000)

b) For susceptible UTI’s: 10 – 20 mg/kg PO q12h for 5-7 days;

For susceptible systemic infections: 22 – 50 mg/kg PO q8h for 7 days;

For susceptible orthopedic infections: 22 – 30 mg/kg IV, IM, SC, or PO q6-8h for 7 – 10 days.

NOTE: Duration of treatment are general guidelines, generally treat for at least 2 days after all signs of infection are gone. (Greene and Watson 1998)

c) For Lyme Disease: 22 mg/kg PO q12h for 21-28 days (Appel and Jacobson 1995)

Cats:

For susceptible infections:

a) For Gram + infections: 10 mg/kg PO, IM, SC twice daily for at least 2 days after symptoms subside.

For Gram – infections: 20 mg/kg PO three times daily or IM, SC twice daily; for at least 2 days after symptoms subside. (Aucoin 2000)

b) For susceptible UTI’s & soft tissue infections 50 mg (total dose per cat) or 11- 22 mg/kg PO once daily for 5-7 days.

For sepsis:: 10 – 20 mg/kg IV, SC, or PO q12h for as long as necessary.

NOTE: Duration of treatment are general guidelines, generally treat for at least 2 days after all signs of infection are gone. (Greene and Watson 1998)

c) C. perfringens, bacterial overgrowth (GI): 22 mg/kg PO once daily for 5 days (Lappin 2000)

Ferrets:

a) For eliminating Helicobacter gastritis infections: Using triple therapy: Metronidazole 22 mg/kg, amoxicillin 22 mg/kg and bismuth subsalicylate (original Pepto-Bismol®) 17.6 mg/kg PO. Give each 3 times daily for 3-4 weeks. (Hall 2000)

b) For susceptible infections: 10 – 35 mg/kg PO or SC twice daily (Williams 2000)

Rabbits/Rodents/Pocket Pets:

a) Hedgehogs: 15 mg/kg IM or PO q12h (Smith 2000)

Cattle:

For susceptible infections:

a) 6 -10 mg/kg SC or IM q24h (Withdrawal time = 30 days). (Jenkins 1986)

b) For respiratory infections: 11 mg/kg IM or SC q12h. (Hjerpe 1986), (Beech 1987b)

c) Calves:Amoxicillin trihydrate: 7 mg/kg PO q8-12h (Baggot 1983)

d) 13.2 – 15.4 mg/kg IM or SC once daily (Upson 1988)

Horses:

For susceptible infections:

a) For respiratory infections: 20 – 30 mg/kg PO q6h (Beech 1987b)

b) Amoxicillin trihydrate: 20 mg/kg q12h IM. (Upson 1988)

c) Foals: Amoxicillin Sodium: 15 – 30 mg/kg IV or IM q6-8h; amoxicillin trihydrate suspension: 25-40 mg/kg PO q8h; amoxicillin/clavulanate 15 – 25 mg/kg IV q6-8h (Brumbaugh 1999)

Birds:

For susceptible infections:

a) For most species: 150 – 175 mg/kg PO once to twice daily (using 50 mg/ml suspension) (Clubb 1986)

b) 100 mg/kg q8h PO (Bauck and Hoefer 1993)

c) 100 mg/kg q8h, IM, SC, PO (Hoeffer 1995)

d) Ratites: 15 – 22 mg/kg PO twice daily; In drinking water: 250 mg/gallon for 3-5 days (Jenson 1998)

Reptiles:

For susceptible infections:

a) For all species: 22 mg/kg PO q12-24h; not very useful unless used in combination with aminoglycosides. (Gauvin 1993)

Client Information

The oral suspension should preferably be refrigerated, but refrigeration is not absolutely necessary; any unused oral suspension should be discarded after 14 days. Amoxicillin may be administered orally without regard to feeding status. If the animal develops gastrointestinal symptoms (e.g., vomiting, anorexia), giving with food may be of benefit.

Medicines containing the active ingredient of amoxicillin (67)

Drug – Active ingredient

CLAMED

Amoksisilin (Amoxicillin) | Klavulanik Asit

AMOKSİD

Amoksisilin (Amoxicillin)

AMOKSİVET ORAL

Amoksisilin (Amoxicillin)

AMOKSİVET ENJ

Amoksisilin (Amoxicillin)

AMOKSİVET TABLET

Amoksisilin (Amoxicillin)

AMOXİNJECT % 15

Amoksisilin (Amoxicillin)

AMOXİNJECT LA

Amoksisilin (Amoxicillin)

AMOXLAV TABLET

Amoksisilin (Amoxicillin) | Klavulanik Asit

AMOXLAV

Amoksisilin (Amoxicillin) | Klavulanik Asit

AMOXY-COL

Amoksisilin (Amoxicillin) | Kolistin

AMOXYCURE

Amoksisilin (Amoxicillin)

AMOXYGEN-F

Amoksisilin (Amoxicillin) | Gentamisin

AMOXYNİL LA

Amoksisilin (Amoxicillin)

ARMALOKS LA

Amoksisilin (Amoxicillin)

AVİCOLİMİSİN

Amoksisilin (Amoxicillin) | Kolistin

BACTİMOX LA

Amoksisilin (Amoxicillin)

BAMOX AQUA VİP

Amoksisilin (Amoxicillin)

BETAMOX LA

Amoksisilin (Amoxicillin)

BİO-AMOXY

Amoksisilin (Amoxicillin)

BOVİMAST LC

Amoksisilin (Amoxicillin) | Klavulanik Asit

BRONDYCEL LA

Amoksisilin (Amoxicillin)

CLAMENTİN PALATABLE

Amoksisilin (Amoxicillin) | Klavulanik Asit

CLAMOXYL

Amoksisilin (Amoxicillin)

CLAMOXYL LA

Amoksisilin (Amoxicillin)

COLAMOX

Amoksisilin (Amoxicillin) | Kolistin

COLMOKSİN

Amoksisilin (Amoxicillin) | Kolistin

DELAMOX % 80

Amoksisilin (Amoxicillin)

FARMOX 150

Amoksisilin (Amoxicillin)

GENTAMOX

Amoksisilin (Amoxicillin) | Gentamisin

HIPRAMOX

Amoksisilin (Amoxicillin)

İLSİVET

Amoksisilin (Amoxicillin)

İNVEMOX LA %15

Amoksisilin (Amoxicillin)

KLAVETSİLİN

Amoksisilin (Amoxicillin) | Klavulanik Asit

KLAVICURE

Amoksisilin (Amoxicillin) | Klavulanik Asit

KLAVİL-LC

Amoksisilin (Amoxicillin) | Klavulanik Asit | Prednisolon

LİNKOSİL

Amoksisilin (Amoxicillin)

LONGAMOX

Amoksisilin (Amoxicillin)

MEDİCAMOX

Amoksisilin (Amoxicillin)

MEGASİL WSP %50

Amoksisilin (Amoxicillin)

MEGASİL CLA

Amoksisilin (Amoxicillin) | Klavulanik Asit

MEGASİL LA

Amoksisilin (Amoxicillin)

MOKSİCOL WSP

Amoksisilin (Amoxicillin) | Kolistin

MOKSİDİF LA

Amoksisilin (Amoxicillin)

MUKOSİLİN

Amoksisilin (Amoxicillin) | Bromheksin

MULTİCİLLİNE WSP

Amoksisilin (Amoxicillin) | Kolistin

NOROCLAV

Amoksisilin (Amoxicillin) | Klavulanik Asit

NOROCLAV LC

Amoksisilin (Amoxicillin) | Klavulanik Asit | Prednisolon

SİMAXY 80

Amoksisilin (Amoxicillin)

SYNERCID

Amoksisilin (Amoxicillin) | Kolistin

SYNOVET

Amoksisilin (Amoxicillin) | Klavulanik Asit

SYNULOX

Amoksisilin (Amoxicillin) | Klavulanik Asit

SYNULOX LC

Amoksisilin (Amoxicillin) | Klavulanik Asit | Prednisolon

SYNULOX TABLET

Amoksisilin (Amoxicillin) | Klavulanik Asit

TEKNOMAX

Amoksisilin (Amoxicillin)

VETAMOKS

Amoksisilin (Amoxicillin)

VİLACOL

Amoksisilin (Amoxicillin) | Kolistin

VİLAMOKS 80

Amoksisilin (Amoxicillin)

VİLAMOKS LA

Amoksisilin (Amoxicillin)

VİMİSİN–K %50

Amoksisilin (Amoxicillin)

VİMİSİN-K %80

Amoksisilin (Amoxicillin)

VİMİSİN–B %70

Amoksisilin (Amoxicillin)

NOVAMOXY

Amoksisilin (Amoxicillin)

NEWAMOX %15 LA

Amoksisilin (Amoxicillin)

CLAVOBAY LC

Amoksisilin (Amoxicillin) | Klavulanik Asit | Prednisolon

CLAVOBAY

Amoksisilin (Amoxicillin) | Klavulanik Asit

AMOXİNJECT % 11.5

Amoksisilin (Amoxicillin)

AMOXLANAT LC

Amoksisilin (Amoxicillin) | Amoksisilin / Klavulanik Asit | Klavulanik Asit