SPOTCLAV 625

Indications

• Bacterial infections
• Urinary tract infections
• Sinusitis
• Uncomplicated community-acquired pneumonia
• Salmonellosis
• Oral infections
• Lyme disease (under expert supervision)
• Acute exacerbation of bronchiectasis
• Anthrax (treatment and post-exposure prophylaxis)

Dosage

Children: 1 month–11 years: 30 mg/kg 3 times a day for 21 days; children 1–4 years: 250 mg 3 times a day; children 5–11 years: 500 mg 3 times a day.

Adults: 500 mg 3 times a day; increased if necessary up to 1 g 3 times a day in severe infections.

Mechanism of action

Amoxicillin works by inhibiting bacterial cell wall synthesis, leading to cell lysis and death. It binds to penicillin-binding proteins (PBPs) located inside the bacterial cell wall, interfering with the transpeptidation process necessary for cell wall integrity.

Pharmacodynamics

Amoxicillin exhibits bactericidal activity against susceptible bacteria. Its action is time-dependent, meaning that its effectiveness is related to the duration of time that the drug concentration remains above the minimum inhibitory concentration (MIC) for the target pathogen.

Pharmacokinetics

Amoxicillin is well absorbed from the gastrointestinal tract, with peak plasma concentrations achieved within 1-2 hours after oral administration. It is widely distributed in body tissues and fluids, and it is excreted primarily via the kidneys. The elimination half-life is approximately 1 hour, and renal impairment may necessitate dosage adjustments.

Adverse effects

• Skin rash
• Gastrointestinal disturbances (nausea, vomiting, diarrhea)
• Allergic reactions (including anaphylaxis)
• Superinfection (due to resistant organisms)

Interactions

• Allopurinol (increases risk of skin rash)

Precautions

• History of penicillin allergy
• Renal impairment (reduce dose)
• Use with caution in patients with mononucleosis

Pregnancy

Use only if clearly needed; no adequate studies in pregnant women.

Breast-feeding

Amoxicillin is excreted in breast milk; use with caution.

Storage

Store in a cool, dry place away from direct sunlight.

Formulations

• Phenoxymethylpenicillin 250mg/5ml oral solution
• Phenoxymethylpenicillin 250 mg tablets

Indications

• Bacterial infections caused by beta-lactamase producing organisms
• Community-acquired pneumonia
• Respiratory tract infections
• Urinary tract infections
• Skin and soft tissue infections

Dosage

Children: Paediatric dosing of clavulanate should be determined based on the specific indication and the formulation used. Refer to the BNF for

Adults: The usual adult dose of clavulanate varies depending on the specific antibiotic it is combined with, generally ranging from 125 mg to 250 mg, taken every 8 hours when combined with amoxicillin.

Mechanism of action

Clavulanate works by irreversibly binding to the active site of beta-lactamase enzymes. By inhibiting these enzymes, clavulanate protects beta-lactam antibiotics from degradation, allowing them to exert their antibacterial effects effectively. This mechanism enhances the spectrum of activity of the co-administered antibiotic, thereby improving clinical outcomes in infections caused by beta-lactamase producing organisms.

Pharmacodynamics

Clavulanate exhibits a time-dependent antibacterial effect, characterized by its ability to maintain effective concentrations against beta-lactamase producing bacteria. Its pharmacodynamic properties are mainly influenced by its interaction with beta-lactam antibiotics, enhancing their efficacy in treating infections. The overall effect is a synergistic relationship that increases the potency of the antibiotic treatment.

Pharmacokinetics

Clavulanate is usually administered orally or parenterally, and it is rapidly absorbed from the gastrointestinal tract. It reaches peak plasma concentrations within 1 to 2 hours after administration. The drug is widely distributed in body tissues, with a volume of distribution indicative of good tissue penetration. Clavulanate undergoes hepatic metabolism, primarily by conjugation, and is excreted largely in the urine as metabolites. The elimination half-life is approximately 1 hour, necessitating frequent dosing for optimal therapeutic effect.

Contra-indications

• Hypersensitivity to clavulanate or any component of the formulation
• History of jaundice or hepatic impairment related to previous use of beta-lactam antibiotics

Adverse effects

• Diarrhea
• Nausea
• Vomiting
• Rash
• Hepatic dysfunction
• Allergic reactions

Interactions

• Probenecid may increase concentrations of clavulanate
• Anticoagulants may have altered effects due to changes in gut flora

Precautions

• Monitor liver function during prolonged therapy
• Use cautiously in patients with renal impairment
• Assess for history of allergy to penicillins or cephalosporins

Pregnancy

Clavulanate is classified as category B. Animal studies have not shown teratogenic effects, but adequate and well-controlled studies in pregnant women are lacking.

Breast-feeding

Clavulanate is excreted in breast milk. Caution is advised when administering to nursing mothers.

Storage

Store in a cool, dry place away from direct light. Keep out of reach of children.

Formulations

• Clavulanate potassium 125 mg/5 mL
• Clavulanate potassium 250 mg/5 mL

Mechanism of action

Amoxicillin competitively inhibits penicillin-binding protein 1 and other high molecular weight penicillin binding proteins. Penicillin bind proteins are responsible for glycosyltransferase and transpeptidase reactions that lead to cross-linking of D-alanine and D-aspartic acid in bacterial cell walls. Without the action of penicillin binding proteins, bacteria upregulate autolytic enzymes and are unable to build and repair the cell wall, leading to bacteriocidal action. The penicillins and their metabolites are potent immunogens because of their ability to combine with proteins and act as haptens for acute antibody-mediated reactions. The most frequent (about 95 percent) or "major" determinant of penicillin allergy is the penicilloyl determinant produced by opening the beta-lactam ring of the penicillin. This allows linkage of the penicillin to protein at the amide group. "Minor" determinants (less frequent) are the other metabolites formed, including native penicillin and penicilloic acids. /Penicillins/ Amoxicillin is similar to penicillin in its bactericidal action against susceptible bacteria during the stage of active multiplication. It acts through the inhibition of cell wall biosynthesis that leads to the death of the bacteria.

Pharmacodynamics

Amoxicillin competitively inhibit penicillin binding proteins, leading to upregulation of autolytic enzymes and inhibition of cell wall synthesis. Amoxicillin has a long duration of action as it is usually given twice daily. Amoxicillin has a wide therapeutic range as mild overdoses are not associated with significant toxicity. Patients should be counselled regarding the risk of anaphylaxis, _Clostridium difficile_ infections, and bacterial resistance.